Silvana Bucher Sandbakk

• Pohle, Carina; Büchel, Daniel; Sandbakk, Silvana Bucher; Sandbakk, Øyvind Bucher; Pletzer, Belinda & Baumeister, Jochen (2026). Uncovering a hidden modulator for women in sports: An exploratory study of menstrual pain and brain connectivity. Women's Health. ISSN 1745-5057. 22. doi: 10.1177/17455057261456871. Full text in Research Archive Show summary

  Background The menstrual cycle (MC), the use of combined oral contraceptives (COCs), and the presence of menstrual pain have long been overlooked factors in female athletes’ health. The influence of hormonal fluctuations and pain may not only alter perceived performance and trainability but could also induce changes in brain network connectivity. Objectives This study aimed to investigate whether resting-state functional connectivity (rsFC) differs between phases across the MC and COC cycle, as well as between naturally cycling (NC) subjects and COC users. A secondary goal was to explore associations between menstrual pain as a covariate and rsFC. Design Observational, longitudinal study. Methods NC women (n = 24) and COC users (n = 17) underwent a resting-state EEG recording during the early follicular phase (EFP) and pre-ovulatory phase (POV), and the active pill phase (pill phase) and inactive phase (pause), respectively. Mean characteristic path length (mCPL), clustering coefficient (CC), and mean debiased weighted phase lag index (mdWPLI) were computed for 37 participants (NC = 21; COC = 16). Phase and group differences were examined using mixed MANOVA, while mixed MANCOVA assessed the influence of menstrual pain as a covariate. Results No significant differences between MC or COC phases, as well as between groups, were found. Including menstrual pain as a covariate revealed significant phase*pain interactions for mCPL and CC, as well as significant group*pain interactions in mdWPLI. Post-hoc tests revealed a significant increase in mCPL from the pause to the pill phase. Conclusion The preliminary findings suggest that menstrual pain may influence baseline brain network states, which may have potential implications for performance and injury risk in female athletes. Therefore, considering menstrual pain is crucial in both research and applied sports contexts.

• Øvstehage, Vemund; Kocbach, Jan Martin; Severin, Anna Cecilia; Skovereng, Knut; Sandbakk, Silvana Bucher & Sandbakk, Øyvind Bucher (2026). Coaches’ perspectives on training quality in elite para-sport: a qualitative study of coach–athlete collaboration. BMC sports science, medicine and rehabilitation. 18(1), p. 1–14. doi: 10.1186/s13102-026-01788-5. Full text in Research Archive Show summary

  Background Training quality is essential for performance development among elite para-athletes. Despite coaches’ central role in structuring and adapting training, little research has explored their perspectives on what constitutes high-quality training. This study investigates which factors elite para-sport coaches perceive as important for achieving high training quality in daily practice. Methods Eight Norwegian coaches with experience at the Paralympic and World Championship level participated in semi-structured interviews. A reflexive thematic analysis was conducted using a hermeneutic-phenomenological approach to identify shared meanings across coaches’ lived experiences. Results Four overarching themes emerged as central to training quality: (1) a supportive training environment (including adapted facilities and integrated support teams), (2) organization and adaptation of the training process (emphasizing collaborative planning and load management), (3) coaches’ understanding of the athlete and sport (highlighting impairment-specific and sport competence), and (4) athlete ownership of training (fostering autonomy and responsibility). These factors were interrelated and influenced both the long-term training process and individual sessions. Coaches described training quality as a dynamic outcome of collaboration between coach, athlete, and support staff, involving continuous dialogue, real-time adjustments, and shared decision-making. Conclusion Elite para-sport coaches perceive training quality as a multifaceted and collaborative process. Key contributions include a well-adapted environment, flexible planning, individualized understanding of athlete needs, and athlete engagement. These findings offer practical insights for enhancing coaching practices in para-sport and underscore the importance of coach–athlete–support team synergy in optimizing performance and well-being.

• Haugen, Tommy; Sandbakk, Øyvind Bucher; Sandbakk, Silvana Bucher & Tønnessen, Espen (2026). Strength and Speed Training Practices for Olympic Endurance Sports: Insights From World-Class Coaches. Journal of Strength and Conditioning Research. ISSN 1064-8011. 40(8), p. 1003–1012. doi: 10.1519/JSC.0000000000005447. Full text in Research Archive Show summary

  Haugen, T, Sandbakk, Ø, Bucher Sandbakk, S, and Tønnessen, E. Strength and speed training practices for Olympic endurance sports: Insights from world-class coaches. J Strength Cond Res 40(8): 1003–1012, 2026—This study aimed to identify common features and sport-specific variations in strength and speed training practices in Olympic endurance sports as described by world-class Norwegian coaches. A multiple case study design was used, and 12 successful male Norwegian coaches served as key informants. Together, they were responsible for athletes winning ∼400 international medals, representing long-distance running, biathlon, rowing, cross-country skiing, speed skating, road cycling, swimming, and triathlon. Data collection was based on a pragmatic 4-step procedure involving questionnaires, training logs, in-depth and semistructured interviews, followed by negotiation among researchers and coaches to assure our interpretations. The present coaches implemented strength and speed training to reduce injury risk, enhance work economy, finish/acceleration capacity, and skeletal health. The total volume of such training ranged from 20 to 200 hours·year−1, depending on sport and contextual factors. The highest volumes and resistance loads were reached during preparation phases, and the strength and speed training were implemented at varying stages of the weekly cycle. Strength sessions typically consisted of 4–8 exercises, 2–4 sets per exercise, 5–10 repetitions per set, and up to 10 repetitions in reserve. The speed training was completed in sport-specific modality with an intensity >90% of maximal velocity. The coaches emphasized strength and speed training as supportive yet secondary to endurance development, often delegating its implementation to the athletes themselves or to specialized staff. The present insights offer valuable contributions to strength and speed training practices in endurance sports and lay the groundwork for future research exploring the effectiveness of these strategies.

• Haugen, Tommy; Sandbakk, Silvana Bucher; Sandbakk, Øyvind Bucher & Tønnessen, Espen (2025). The training and development process for a world-class female handball player: a longitudinal and retrospective case study. Frontiers in Sports and Active Living. 7. doi: 10.3389/fspor.2025.1655916. Full text in Research Archive
• Sandbakk, Øyvind Bucher; Herzog, Sophie; McGawley, Kerry; Pyne, David B.; Talsnes, Rune Kjøsen & Millet, Grégoire P. [Show all 17 contributors for this article] (2025). Perspectives of World-Class Endurance Coaches on the Evolution of Athlete Training and Performance. International Journal of Sports Physiology and Performance (IJSPP). ISSN 1555-0265. 21(1), p. 98–105. doi: 10.1123/ijspp.2025-0317. Full text in Research Archive Show summary

  Purpose : To provide insights into the key practices driving the evolution of endurance training and performance. Methods : A total of 78 world-class coaches (73 men, 5 women), representing 14 endurance sports, and 18 nations, participated in a digital survey comprising open-ended questions about recent trends and projected future developments. Results : Qualitative thematic analysis revealed 8 key drivers of change: (1) individualized and sport-specific training strategies, (2) precision in training execution, (3) load-management procedures, (4) strategic use of environmental stressors, (5) optimized nutrition, (6) holistic recovery practices, (7) health and injury prevention, and (8) equipment and technology-driven innovation. To provide a clearer conceptual framework, these themes were grouped into 3 overarching categories: training methodologies (themes 1–4), recovery and health management (themes 5–7), and technological innovation (theme 8). Conclusions : World-class endurance coaches describe a continuing shift toward more individualized training strategies, characterized by detailed sport-specific considerations, training plans aligned with physiological profiles, greater precision in training execution, refined load management, and strategic use of environmental stressors. In this context, advanced monitoring technologies are viewed as essential for optimizing training adaptations while minimizing the risk of maladaptation and injury. Coaches also emphasized the importance of enhanced health and recovery strategies to support training adaptations, including sleep quality, stress management, life balance, and targeted nutritional interventions, particularly carbohydrate availability. Finally, the rapid development of new equipment and technologies is transforming training and coaching practices, thereby contributing to improved endurance performance.

• Tønnessen, Espen; Sandbakk, Silvana Bucher; Apold-Aasen, Sigmund B.; Sandbakk, Øyvind Bucher & Haugen, Tommy (2025). The training and development process during childhood and adolescence of a multiple Ballon d'Or-nominated soccer player. Frontiers in Sports and Active Living. 7. doi: 10.3389/fspor.2025.1710194. Full text in Research Archive
• Øvstehage, Vemund; Sandbakk, Silvana Bucher; Kocbach, Jan Martin & Sandbakk, Øyvind Bucher (2025). Exploring key factors associated with training quality among elite para-athletes. A qualitative study. Frontiers in Sports and Active Living. 7. doi: 10.3389/fspor.2025.1561641. Full text in Research Archive Show summary

  Introduction: Despite extensive research on training load characteristics, knowledge about training quality remains sparse. Training quality encompasses two dimensions: quality in the training process and quality in specific training sessions. Elite para-athletes perform high volumes of training, and their training execution may be further influenced by their impairment and sport. No research has explored training quality among elite para-athletes. Therefore, the aim of this study was to qualitatively explore key factors associated with training quality among elite para-athletes across different impairments and sports. Methods: A hermeneutic phenomenological approach was applied to conduct semi-structured interviews with 21 Norwegian current and former elite para-athletes (10 women and 11 men) from ten sports and five impairment categories. A reflexive thematic analysis was conducted to inductively explore the experiences and perspectives related to training quality in the training process and specific training sessions. Methodological integrity was ensured through transparency, reflexivity, and member reflection. Results: Similar overarching themes emerged for the quality of the training process and specific training sessions: (1) Planning and preparation (with themes such as goal setting, recovery strategies, and equipment optimization), (2) Training execution (with themes such as training load management, awareness, and solution-oriented modification of training), and (3) Coaching and training support (with themes such as trustful coach–athlete relationship, individualized interdisciplinary support, and supportive social and professional networks). These themes could influence the quality in each dimension to different extents, depending on the specific impairment and sport, and could either enhance or diminish training quality, depending on how they were addressed. Conclusions: Based on the experiences of 21 elite para-athletes, this study highlights the importance of planning and preparation, deliberate execution of training, and a competent coaching and support team to influence training quality both in the training process and specific training sessions. The extent to which the underlying factors may impact training quality, depends on impairment and sport. Athletes may improve training quality by making deliberate decisions tailored to their unique prerequisites, goals and resources. Knowledge of these factors can inform para-athletes and coaches in their efforts to enhance quality in the training process and specific training sessions.

• Sandbakk, Øyvind Bucher; Tønnessen, Espen; Sandbakk, Silvana Bucher; Losnegard, Thomas Johansen; Seiler, Stephen & Haugen, Thomas André (2025). Best-Practice Training Characteristics Within Olympic Endurance Sports as Described by Norwegian World-Class Coaches. Sports Medicine - Open. 11. doi: 10.1186/s40798-025-00848-3. Full text in Research Archive Show summary

  Background World-class coaches collect training data from their athletes systematically and exhibit an experimental mindset when making individual training adjustments in response to this data and other forms of feedback. However, the methods, expertise, and insights of highly accomplished endurance coaches is so far almost untouched in the scientific literature. The aim of this study was to provide a synthesis of common features and sport-specific variations in best-practice training characteristics within Olympic endurance sports as described by world-class Norwegian coaches. Methods A multiple case-study design was used, and twelve successful male Norwegian coaches served as key informants. Together, they were responsible for athletes winning more than 380 international medals, representing long-distance running, biathlon, rowing, cross-country skiing, speed skating, road cycling, swimming, and triathlon. The study design included: (1) an extensive, email-administered and Word™-based questionnaire related to training characteristics at the macro-, meso-, micro-, and session-level; (2) cross-referencing data with historically reported training logs from successful athletes; (3) in-depth and semi-structured in-person interviews with each coach; (4) a review process among authors and coaches. The data collection was undertaken in 2022. Results All coaches adhere to a traditional periodization model, including a gradual shift towards lower overall training volume and more competition-specific training as the competitive period approaches. The coaches also employ a pragmatic approach to align training organization with the various constraints faced in the training process. Another common emerging feature was an emphasis on high volume of low-intensity training combined with 2–3 weekly “key workout” days consisting of 3–5 intensive training sessions. Finally, coaches across all sports focused on achieving high training quality by optimizing training sessions, systematically controlling the load-recovery balance, and ensuring optimal preparations for major competitions. Substantial sport-specific differences were evident in terms of volume, frequency, intensity distribution, and application of strength and cross training, mainly due to variations in exercise mode constraints (i.e., mechanical, and muscular loading), competition distance, and organizational aspects. Conclusions This study offers novel insights into best-practice training characteristics in Olympic endurance, shedding light on both commonalities and sport-specific variations. These insights can be used to generate new hypotheses to be further elucidated and contribute to the development of evidence-based training practices.

• Svenningsen, Alexander Robert; Søderstrøm, Sylvia; Sandbakk, Silvana Bucher; Gullestad, Lars; Bønaa, Kaare Harald & Wisløff, Ulrik [Show all 7 contributors for this article] (2024). Mind the intention-behavior gap: a qualitative study of post-myocardial infarction patients’ beliefs and experiences with long-term supervised and self-monitored physical exercise. BMC sports science, medicine and rehabilitation. 16(1). doi: 10.1186/s13102-024-00987-2. Full text in Research Archive Show summary

  Background Many post-myocardial infarction (MI) patients struggle with physical activity behavior change (BC) for life-long secondary prevention. There is limited knowledge about factors influencing long-term physical activity BC among post-MI patients. This qualitative study aimed to explore the beliefs and experiences related to post-MI patients’ physical activity BC process following a year’s participation in a supervised and self-monitored exercise program: the Norwegian Trial of Physical Exercise After MI (NorEx). Methods We conducted a qualitative study, performing in-depth semi-structured interviews with a randomly selected sample of NorEx participants when they were scheduled for cardiopulmonary exercise testing after one year of participation. Interviews were transcribed verbatim and the data was analyzed by applying reflexive thematic analysis. Results Seventeen participants (n = 4 female [24%]; median age, 61 years; median time since index MI, 4 years) were recruited and interviewed once. Analysis resulted in four main themes (nine sub-themes): (1) Personal responsibility to exercise (Exercise is safe, Health benefits, Habitual exercise); (2) Peer social support for a sense of safety and belonging (Social exercise, Supervision is preferred); (3) Research participation transformed exercise beliefs (High-intensity exercise is superior, Personal Activity Intelligence (PAI) promotes exercise adherence); and (4) Mind the intention-behavior gap (Initial anxiety, Lack of continued follow-up). Conclusions Several participants reported that they were able to maintain exercise BC during a year’s participation in NorEx. Nevertheless, a perceived lack of continued and individualized follow-up made some participants struggle with motivation and self-regulation, leading to an intention-behavior gap. Therefore, our findings suggest there is a need for individualized and continued social support and supervision from health and exercise professionals to maintain long-term exercise BC for secondary prevention among post-MI patients. Trial registration The NorEx study has been registered at ClinicalTrials.gov (NCT04617639, registration date 2020-10-21).

• Tønnessen, Espen; Sandbakk, Øyvind Bucher; Sandbakk, Silvana Bucher; Seiler, Stephen & Haugen, Tommy (2024). Training Session Models in Endurance Sports: A Norwegian Perspective on Best Practice Recommendations. Sports Medicine. ISSN 0112-1642. 54, p. 2935–2953. doi: 10.1007/s40279-024-02067-4. Full text in Research Archive Show summary

  Background: Our scientific understanding of the mechanistic and practical connections between training session prescriptions, their execution by athletes, and adaptations over time in elite endurance sports remains limited. These connections are fundamental to the art and science of coaching. Objective: By using successful Norwegian endurance coaches as key informants, the aim of this study is to describe and compare best practice session models across different exercise intensities in Olympic endurance sports. Methods: Data collection was based on a four-step pragmatic qualitative study design, involving questionnaires, training logs from successful athletes, and in-depth and semi-structured interviews, followed by negotiation among researchers and coaches to assure our interpretations. Twelve successful and experienced male Norwegian coaches from biathlon, cross-country skiing, long-distance running, road cycling, rowing, speed skating, swimming, and triathlon were chosen as key informants. They had been responsible for the training of world-class endurance athletes who altogether have won > 370 medals in international championships. Results: The duration of low-intensity training (LIT) sessions ranges from 30 min to 7 h across sports, mainly due to modality-specific constraints and load tolerance considerations. Cross-training accounts for a considerable part of LIT sessions in several sports. Moderate (MIT)- and high-intensity training (HIT) sessions are mainly conducted as intervals in specific modalities, but competitions also account for a large proportion of annual HIT in most sports. Interval sessions are characterized by a high accumulated volume, a progressive increase in intensity throughout the session, and a controlled, rather than exhaustive, execution approach. A clear trend towards shorter intervals and lower work: rest ratio with increasing intensity was observed. Overall, the analyzed sports implement considerably more MIT than HIT sessions across the annual cycle. Conclusions: This study provides novel insights on quantitative and qualitative aspects of training session models across intensities employed by successful athletes in Olympic endurance sports. The interval training sessions revealed in this study are generally more voluminous, more controlled, and less exhaustive than most previous recommendations outlined in research literature.

• Talsnes, Rune Kjøsen; Tønnessen, Espen; Sandbakk, Silvana Bucher; Haugen, Thomas André & Sandbakk, Øyvind Bucher (2024). Warning Signs, Monitoring Tools, and Actions Taken by World-Class Endurance Coaches in Cases of Underperformance. International Journal of Sports Physiology and Performance (IJSPP). ISSN 1555-0265. 20(2), p. 238–245. doi: 10.1123/ijspp.2024-0161. Full text in Research Archive
• Haugen, Thomas André; Ruud, Caroline; Sandbakk, Silvana Bucher; Sandbakk, Øyvind Bucher & Tønnessen, Espen (2024). The Training and Development Process for a Multiple-Grand-Slam Finalist in Tennis. International Journal of Sports Physiology and Performance (IJSPP). ISSN 1555-0265. 19(11), p. 1247–1255. doi: 10.1123/ijspp.2024-0132. Full text in Research Archive
• Johansen, Kristoffer Robin; Ranhoff, Anette Hylen; Sørensen, Eivind; Nes, Bjarne Martens; Sandbakk, Silvana Bucher & Wilsgaard, Tom [Show all 9 contributors for this article] (2023). Ten-year mortality among older male recreational endurance athletes in the Birkebeiner Aging Study in comparison with older men from the Tromsø Study - PubMed. Scandinavian Journal of Medicine & Science in Sports. ISSN 0905-7188. 33(8), p. 1541–1551. doi: 10.1111/sms.14385. Full text in Research Archive Show summary

  Endurance sport practice was associated with reduced 10-year mortality, beyond the effect of PA in older men. This study suggests that long-term endurance sport practice maintained into older adulthood promotes longevity.

• Johansen, Kristoffer Robin; Ranhoff, Anette Hylen; Sørensen, Eivind; Nes, Bjarne Martens; Sandbakk, Silvana Bucher & Wilsgaard, Tom [Show all 10 contributors for this article] (2023). Ten-year mortality among older male recreational endurance athletes in the Birkebeiner Aging Study in comparison with older men from the Tromsø Study. Scandinavian Journal of Medicine & Science in Sports. ISSN 0905-7188. 33(8), p. 1541–1551. doi: 10.1111/sms.14385. Full text in Research Archive Show summary

  Background Physical activity (PA) is associated with reduced mortality. However, whether there is an added benefit of long-term endurance training is unclear. Thus, we aimed to examine 10-year mortality in older male endurance athletes compared with an older male general population. Method Male athletes (n = 503) participating in an annual long-distance ski race (median years of participation: 14, range: 1–53) from the Norwegian Birkebeiner Aging study (BiAS), and non-athletic men (n = 1867) attending the sixth Tromsø Study (Tromsø6) aged ≥65 years were included. Associations with endurance sport practice and joint exposures of endurance sport practice and self-reported leisure-time PA with all-cause mortality were examined. We analyzed the data with Cox proportional hazard models and regression standardization. Results After 10 years (median: 10.4, range: 0.5–11.1) the mortality rate was lower in athletes (hazard ratio (HR) 0.34, 95% confidence interval (CI): 0.24–0.49) compared with non-athletes, corresponding to a 15% (95% CI: 12–19%) absolute risk reduction associated with endurance sport practice. In joint analyses categorized according to PA and endurance sport practice, we observed an inverse dose–response relationship with mortality (p < 0.001). Compared to inactive non-athletes, PA was associated with lower mortality in both active non-athletes and athletes. However, the observed benefit among participants reporting moderate-to-vigorous PA was larger in athletes (HR: 0.21, 95% CI: 0.14–0.32) than non-athletes (HR: 0.43, 95% CI: 0.31–0.59) (p < 0.01). Conclusion Endurance sport practice was associated with reduced 10-year mortality, beyond the effect of PA in older men. This study suggests that long-term endurance sport practice maintained into older adulthood promotes longevity.

• Severin, Anna Cecilia; Skovereng, Knut; Björklund, Glenn; Hemmestad, Liv B; Sandbakk, Øyvind Bucher & Sandbakk, Silvana Bucher (2023). New insights from Norwegian and Swedish sports coaches' employment, practices, and beliefs during the first COVID-19 restriction period. Frontiers in Sports and Active Living. 5. doi: 10.3389/fspor.2023.1277228. Full text in Research Archive Show summary

  Introduction: This study (i) examined Norwegian and Swedish sports coaches' employment, practices, and beliefs during the first wave of the COVID-19 pandemic, (ii) compared these aspects between coaches in Norway and Sweden, two countries with clearly different movement restrictions strategies in this period. Methods: An online survey was distributed to coaches via email and social media. The survey was open between June and August 2020. In total, 348 coaches responded, 141 from Norway, and 207 from Sweden. Results: Among responders, 2% had lost their job due to the pandemic, 17% had been furloughed, 28% worked from home office, and 39% worked as usual. Norwegian coaches were more likely to work from home (48% vs. 15%, p < .001), while Swedish coaches were more likely to work as usual (60% vs. 9%, p < .001). Coaches in both countries communicated less frequently with their athletes (p < .001) and had less in-person communication (p < .001) compared to pre-Covid levels. Larger declines existed among Norwegian coaches regarding communication frequency (p < .001) and in-person communication (p < .001). Video calls and phone calls usage increased (p < .001 and p = .009 respectively). We recorded low levels of concern among coaches about the effects of the pandemic on their relationship with their athletes. There were considerable levels of concern about athletes’ maintaining their motivation to train (Norway: 43.3%, Sweden: 50.7%), and low levels of concern about the coaches’ relationships with their athletes (Norway: 14.1%, Sweden: 17.8%). Discussion: Overall, this study showed the imposed movement restrictions had several negative consequences for the employment and work practices of sports coaches in Norway and Sweden. However, it also highlighted that coaches were able to adapt their work practices to the constraints and were able to maintain relationships with their athletes. The consequences raised in this paper can act as a guide during possible future lockdowns.

• Sandbakk, Øyvind Bucher; Pyne, David B.; McGawley, Kerry; Foster, Carl; Talsnes, Rune Kjøsen & Solli, Guro Strøm [Show all 16 contributors for this article] (2023). The Evolution of World-Class Endurance Training: The Scientist's View on Current and Future Trends. International Journal of Sports Physiology and Performance (IJSPP). ISSN 1555-0265. 18(8), p. 885–889. doi: 10.1123/ijspp.2023-0131. Full text in Research Archive Show summary

  Background: Elite sport is continuously evolving. World records keep falling and athletes from a longer list of countries are involved. Purpose: This commentary was designed to provide insights into present and future trends associated with world-class endurance training based on the perspectives, experience, and knowledge of an expert panel of 25 applied sport scientists. Results: The key drivers of development observed in the past 10–15 years were related to (1) more accessible scientific knowledge for coaches and athletes combined with (2) better integration of practical and scientific exchange across multidisciplinary perspectives within professionalized elite athlete support structures, as well as (3) utilization of new technological advances. Based on these perspectives, we discerned and exemplified the main trends in the practice of endurance sports into the following categories: better understanding of sport-specific demands; improved competition execution; larger, more specific, and more precise training loads; improved training quality; and a more professional and healthier lifestyle. The main areas expected to drive future improvements were associated with more extensive use of advanced technology for monitoring and prescribing training and recovery, more precise use of environmental and nutritional interventions, better understanding of athlete– equipment interactions, and greater emphasis on preventing injuries and illnesses. Conclusions: These expert insights can serve as a platform and inspiration to develop new hypotheses and ideas, encourage future collaboration between researchers and sport practitioners, and, perhaps most important, stimulate curiosity and further collaborative studies about the training, physiology, and performance of endurance athletes.

• Johansen, Kristoffer Robin; Ranhoff, Anette Hylen; Sørensen, Eivind; Nes, Bjarne; Heitmann, Kim Arne & Apelland, Turid [Show all 12 contributors for this article] (2022). Risk of atrial fibrillation and stroke among older men exposed to prolonged endurance sport practice: a 10-year follow-up. The Birkebeiner Ageing Study and the Tromsø Study. Open heart. 9(2). doi: 10.1136/openhrt-2022-002154. Full text in Research Archive Show summary

  Aims Endurance sport practice is associated with a high prevalence of atrial fibrillation (AF), which increases the risk of stroke in the general population. However, stroke risk in endurance athletes with AF is sparsely investigated. Most studies have been limited by design and are largely restricted to younger and middle-aged populations. Thus, we aimed to investigate AF and stroke risk in older athletes exposed to prolonged endurance training. Method During a 10-year period, 505 male athletes aged ≥65 years frequently participating in a long-distance ski race were compared with 1867 men of the same age from the general population. The main exposure was endurance sport practice with self-reported AF and stroke as outcomes. Stroke risk was further examined by joint modelling of AF and endurance practice. Statistical analysis was conducted with a modified Poisson model. Results Athletes (median age: 68, range: 65–90) participated in a long-distance ski race over a median of 14 years (range: 1–53). Prevalence (28.5% vs 17.8%) and adjusted risk of AF (risk ratio (RR): 1.88, 95% CI: 1.49 to 2.37) were higher in athletes compared with non-athletes, whereas the prevalence (5.4% vs 9.7%) and risk of stroke were lower (RR: 0.60, 95% CI: 0.37 to 0.95). Compared with athletes without AF, risk of stroke was twofold in athletes (RR: 2.38, 95% CI: 1.08 to 5.24) and nearly fourfold in non-athletes (RR: 3.87, 95% CI: 1.98 to 7.57) with AF. Conclusion Although older male endurance athletes experienced an increased risk of AF, the long-term risk of stroke was substantially reduced compared with non-athletes.

• Sandbakk, Silvana Bucher; Tønnessen, Espen; Haugen, Thomas André & Sandbakk, Øyvind (2022). Training and Coaching of Female vs. Male Endurance Athletes on their Road to Gold. Perceptions among Successful Elite Athlete Coaches. Deutsche Zeitschrift für Sportmedizin. ISSN 0344-5925. 73(7), p. 251–258. doi: 10.5960/dzsm.2022.549. Full text in Research Archive Show summary

  This scientific short report investigated how successful male coaches perceive gender differences in training characteristics and coaching practice among medal-winning endurance athletes.<p> <p>Ten male Norwegian coaches with a track record of coaching both female and male endurance world-class athletes (total of 269 Olympic, World and European Championship medals) participated in semi-structured interviews. Inductive thematic analysis revealed that all coaches mainly adjusted their key training and coaching principles to the individual athlete, rather than gender. A coach-driven and athlete-centered individualization process was essential to create trust, mutual understanding, and optimal training content. Potential gender/sex differences were perceived in four main themes: sport-specific competition demands, physiological, psychological and interpersonal factors (e.g., gender of the coach). <p>In this context, all coaches described how training and coaching of female athletes differs from that of men, thus considering male athletes as the reference group and male physiology and psychology as the norm. Furthermore, societal factors such as a male-dominant sports culture and underlying gender stereotypes were suggested as amplifiers of gender differences. <p>Accordingly, our report highlights the need for female perspectives in elite sports and invites further in-depth investigations of the identified gender/sex differences within the respective disciplines of training science, physiology, psychology and sociology.

• Heikura, Ida A.; Kettunen, Oona; Garthe, Ina; Holmlund, Heidi; Sandbakk, Silvana Bucher & Valtonen, Maarit [Show all 7 contributors for this article] (2021). Energetic Demands and Nutritional Strategies of Elite Cross-Country Skiers During Tour de Ski: A Narrative Review. Journal of Science in Sport and Exercise (SSEJ). ISSN 2096-6709. 3(3), p. 224–237. doi: 10.1007/s42978-020-00105-x. Full text in Research Archive
• Letnes, Jon Magne; Berglund, Ida Johnsen; Johnson, Kristin Espolin; Dalen, Håvard; Nes, Bjarne & Lydersen, Stian [Show all 25 contributors for this article] (2021). Effect of 5 years of exercise training on the cardiovascular risk profile of older adults: the Generation 100 randomized trial. European Heart Journal. ISSN 0195-668X. 43(21), p. 2065–2075. doi: 10.1093/eurheartj/ehab721. Full text in Research Archive Show summary

  Aims The aim of this study was to compare the effects of 5 years of supervised exercise training (ExComb), and the differential effects of subgroups of high-intensity interval training (HIIT) and moderate-intensity continuous training (MICT), with control on the cardiovascular risk profile in older adults. Methods and results Older adults aged 70–77 years from Trondheim, Norway (n = 1567, 50% women), able to safely perform exercise training were randomized to 5 years of two weekly sessions of HIIT [∼90% of peak heart rate (HR), n = 400] or MICT (∼70% of peak HR, n = 387), together forming ExComb (n = 787), or control (instructed to follow physical activity recommendations, n = 780). The main outcome was a continuous cardiovascular risk score (CCR), individual cardiovascular risk factors, and peak oxygen uptake (VO2peak). CCR was not significantly lower [−0.19, 99% confidence interval (CI) −0.46 to 0.07] and VO2peak was not significantly higher (0.39 mL/kg/min, 99% CI −0.22 to 1.00) for ExComb vs. control. HIIT showed higher VO2peak (0.76 mL/kg/min, 99% CI 0.02–1.51), but not lower CCR (−0.32, 99% CI −0.64 to 0.01) vs. control. MICT did not show significant differences compared to control or HIIT. Individual risk factors mostly did not show significant between-group differences, with some exceptions for HIIT being better than control. There was no significant effect modification by sex. The number of cardiovascular events was similar across groups. The healthy and fit study sample, and contamination and cross-over between intervention groups, challenged the possibility of detecting between-group differences. Conclusions Five years of supervised exercise training in older adults had little effect on cardiovascular risk profile and did not reduce cardiovascular events. ClinicalTrials.gov: NCT01666340

• Solli, Guro Strøm; Kocbach, Jan; Sandbakk, Silvana Bucher; Haugnes, Pål; Losnegard, Thomas & Sandbakk, Øyvind (2020). Sex-based differences in sub-technique selection during an international classical cross-country skiing competition. PLOS ONE. 15(9). doi: 10.1371/journal.pone.0239862. Full text in Research Archive Show summary

  The purpose of this study was to compare speed, sub-technique selection and temporal patterns between world-class male and female cross-country (XC) skiers and to examine the combined associations of sex and speed on sub-technique selection. Thirty-three XC skiers performed an international 10-km (women; n = 8) and 15-km (men; n = 25) time-trial competition in the classical style (with the first 10 km of the race being used for analyses). An integrated GNSS/IMU system was used to continuously track position speed and automatically classify sub-techniques and temporal patterns (i.e. cycle length and–rate). When comparing the eight highest ranked men and women, men spent less time than women (29±2 vs. 45±5% of total time) using diagonal stride (DIA), more time (44±4 vs. 31±4%) using double poling (DP) and more time (23±2 vs. 19±3%) using tucking and turning (all P < .01). Here, men and women used these sub-techniques at similar temporal patterns within the same speed-intervals; although men employed all sub-techniques at steeper uphill gradients (all P < .05). In subsequent analyses including all 33 skiers, adjustment for average racing speed did not fully attenuate the observed sex differences in the proportion of time using DIA (CI95% [-10.7, -1.6]) and DP (CI95% [0.8, 9.3]). Male world-class XC skiers utilized less DIA and more DP compared to women of equal performance levels. Although these differences coincided with men’s higher speed and their ability to use the various sub-techniques at steeper uphill gradients, sexual dimorphism in the proportional use of DIA and DP also occurred independently of these speed-differences.

• Solli, Guro Strøm; Sandbakk, Silvana Bucher; Noordhof, Dionne; Ihalainen, Johanna K. & Sandbakk, Øyvind (2020). Changes in self-reported physical fitness, performance, and side effects across the phases of the menstrual cycle among competitive endurance athletes. International Journal of Sports Physiology and Performance (IJSPP). ISSN 1555-0265. 15(9), p. 1324–1333. doi: 10.1123/IJSPP.2019-0616. Full text in Research Archive Show summary

  Purpose: To investigate changes in self-reported physical fitness, performance, and side effects across the menstrual cycle (MC) phases among competitive endurance athletes and to describe their knowledge and communication with coaches about the MC. Methods: The responses of 140 participants (older than 18 y) competing in biathlon or cross-country skiing at the (inter)national level were analyzed. Data were collected via an online questionnaire addressing participants' competitive level, training volume, MC history, physical fitness, and performance during the MC, MC-related side effects, and knowledge and communication with coaches about the MC and its effects on training and performance. Results: About 50% and 71% of participants reported improved and reduced fitness, respectively, during specific MC phases, while 42% and 49% reported improved and reduced performance, respectively. Most athletes reported their worst fitness (47%) and performance (30%) and the highest number of side effects during bleeding (P < .01; compared with all other phases). The phase following bleeding was considered the best phase for perceived fitness (24%, P < .01) and performance (18%, P < .01). Only 8% of participants reported having sufficient knowledge about the MC in relation to training, and 27% of participants communicated about it with their coach. Conclusions: A high proportion of athletes perceived distinct changes in fitness, performance, and side effects across the MC phases, with their worst perceived fitness and performance during the bleeding phase. Because most athletes indicate a lack of knowledge about the MC's effect on training and performance and few communicate with coaches on the topic, the authors recommend that more time be devoted to educating athletes and coaches.

• Stensvold, Dorthe; Viken, Hallgeir; Steinshamn, Sigurd Loe; Dalen, Håvard; Støylen, Asbjørn & Loennechen, Jan Pål [Show all 23 contributors for this article] (2020). Effect of exercise training for five years on all cause mortality in older adults-The Generation 100 study: Randomised controlled trial. The BMJ. 371. doi: 10.1136/bmj.m3485. Full text in Research Archive Show summary

  Objective To evaluate the effect of five years of supervised exercise training compared with recommendations for physical activity on mortality in older adults (70-77 years). Design Randomised controlled trial. Setting General population of older adults in Trondheim, Norway. Participants 1567 of 6966 individuals born between 1936 and 1942. Intervention Participants were randomised to two sessions weekly of high intensity interval training at about 90% of peak heart rate (HIIT, n=400), moderate intensity continuous training at about 70% of peak heart rate (MICT, n=387), or to follow the national guidelines for physical activity (n=780; control group); all for five years. Main outcome measure All cause mortality. An exploratory hypothesis was that HIIT lowers mortality more than MICT. Results Mean age of the 1567 participants (790 women) was 72.8 (SD 2.1) years. Overall, 87.5% of participants reported to have overall good health, with 80% reporting medium or high physical activity levels at baseline. All cause mortality did not differ between the control group and combined MICT and HIIT group. When MICT and HIIT were analysed separately, with the control group as reference (observed mortality of 4.7%), an absolute risk reduction of 1.7 percentage points was observed after HIIT (hazard ratio 0.63, 95% confidence interval 0.33 to 1.20) and an absolute increased risk of 1.2 percentage points after MICT (1.24, 0.73 to 2.10). When HIIT was compared with MICT as reference group an absolute risk reduction of 2.9 percentage points was observed (0.51, 0.25 to 1.02) for all cause mortality. Control participants chose to perform more of their physical activity as HIIT than the physical activity undertaken by participants in the MICT group. This meant that the controls achieved an exercise dose at an intensity between the MICT and HIIT groups. Conclusion This study suggests that combined MICT and HIIT has no effect on all cause mortality compared with recommended physical activity levels. However, we observed a lower all cause mortality trend after HIIT compared with controls and MICT.

• Medeiros, Leonardo H.L.; Sandbakk, Silvana Bucher; Bertazone, Thais Mara Alexandre & Bueno, Carlos Roberto (2020). Comparison of Periodization Models of Concurrent Training in Recreationally Active Postmenopausal Women. Journal of Strength and Conditioning Research. ISSN 1064-8011. 36(4), p. 977–983. doi: 10.1519/jsc.0000000000003559. Full text in Research Archive
• Croci, Ilaria; Coombes, Jeff S.; Sandbakk, Silvana Bucher; Keating, Shelley E.; Nauman, Javaid & Macdonald, Graeme A. [Show all 7 contributors for this article] (2019). Non-alcoholic fatty liver disease: Prevalence and all-cause mortality according to sedentary behaviour and cardiorespiratory fitness. The HUNT Study. Progress in cardiovascular diseases. ISSN 0033-0620. 62(2), p. 127–134. doi: 10.1016/j.pcad.2019.01.005. Full text in Research Archive
• Reitlo, Line Skarsem; Sandbakk, Silvana Bucher; Viken, Hallgeir; Aspvik, Nils Petter; Ingebrigtsen, Jan Erik & Tan, Xiang chun [Show all 8 contributors for this article] (2018). Exercise patterns in older adults instructed to follow moderate- or high-intensity exercise protocol - the generation 100 study. BMC Geriatrics. 18(1). doi: 10.1186/s12877-018-0900-6. Full text in Research Archive Show summary

  Background Making older adults exercise and keeping them in exercise programs is a major challenge. Understanding how older adults prefer to exercise may help developing tailored exercise programs and increase sustained exercise participation in ageing populations. We aimed to describe exercise patterns, including frequency, intensity, type, location and social setting of exercise, in older adults instructed to follow continuous moderate-intensity training (MCT) or high-intensity interval training (HIIT) over a one-year period. Methods Frequency, intensity, type, location and social setting (alone vs. together with others) of exercise were assessed using exercise logs from 618 older adults (aged 70–77 years) randomized to MCT or HIIT. All participants completed exercise logs after each exercise session they performed during one year. Pearson Chi-square tests were run to assess the association between intensity, type, location and social setting of exercise with training group. Results Both groups performed 2.2 ± 1.3 exercise sessions per week during the year. Walking was the most common exercise type in both groups, but MCT had a higher proportion of walking sessions than HIIT (54.2% vs. 41.1%, p < 0.01). Compared to MCT, HIIT had a higher proportion of sessions with cycling (14.2% vs. 9.8%, p < 0.01), combined endurance and resistance training (10.3% vs. 7.5%, p < 0.01), jogging (6.5% vs. 3.2%, p < 0.01) and swimming (2.6% vs. 1.7%, p < 0.01). Outdoors was the most common exercise location in both training groups (67.8 and 59.1% of all sessions in MCT and HIIT, respectively). Compared to MCT, HIIT had a higher proportion of sessions at a gym (21.4% vs. 17.5%, p < 0.01) and sports facility (9.8% vs. 7.6%, p < 0.01). Both groups performed an equal amount of sessions alone and together with others, but women had a higher proportion of sessions together with others compared to men (56% vs. 44%, p < 0.01). Conclusion This is the first study that has followed older adults instructed to perform MCT or HIIT over a one-year period, collected data from each exercise session they performed and provided important knowledge about their exercise patterns. This novel information may help researchers and clinicians to develop tailored exercise programs in an ageing population.

• Zisko, Nina; Nauman, Javaid; Sandbakk, Silvana Bucher; Aspvik, Nils Petter; Salvesen, Øyvind & Carlsen, Trude [Show all 10 contributors for this article] (2017). Absolute and relative accelerometer thresholds for determining the association between physical activity and metabolic syndrome in the older adults: The Generation-100 study. BMC Geriatrics. 17(1). doi: 10.1186/s12877-017-0497-1. Full text in Research Archive Show summary

  Background When assessing population adherence to physical activity (PA) recommendation using accelerometers, absolute intensity threshold definition is applied despite having limited validity in those with low cardiorespiratory fitness (CRF), who are unable to reach them (e.g older adults). Thus, PA thresholds relative to CRF may be an alternative approach. We compared the proportion of the older adults meeting the PA recommendation when PA is assessed using absolute versus sex-and-CRF-adjusted (relative) accelerometer thresholds and determined the association between relative versus absolute moderate PA (MPA), vigorous PA (VPA) and moderate-to-vigorous PA (MVPA) and metabolic syndrome (MetS). Methods Cross-sectional study of 509 men and 567 women aged 70–77. Accelerometer assessed MPA, VPA and MVPA were analyzed using absolute and relative thresholds. Meeting the PA-recommendation was defined as amounting ≥150 min/week in MPA/MVPA or 75 min/week in VPA, respectively. CRF was directly measured as peak oxygen uptake (VO2peak). MetS was defined as 3 or more of the following: elevated waist circumference, fasting glucose, hypertension, triglycerides, decreased HDL-cholesterol or diabetes, dyslipidemia or hypertension medication. Results Higher proportion of the population met the recommendation when PA was assessed with relative compared to absolute thresholds: VPA (72.4% vs. 1.7%) and MVPA (75.2% vs. 33.8%). Logistic regression analysis revealed that men and women not meeting the relative-MVPA or VPA recommendation had higher likelihood of MetS (Men: MVPA OR: 1.59, 95% CI: 1.08–2.33. VPA OR: 1.81, 95%CI: 1.23–2.67 and Women: MVPA OR: 2.12, 95% CI: 1.36–3.31; VPA OR: 1.95, 95% CI: 1.29–2.95), compared to men and women meeting the relative MVPA or VPA recommendation. There was no significant association between MetS and absolute MVPA, MPA or VPA recommendations in the fully adjusted model. Conclusions The association between meeting/not meeting the PA recommendation and MetS differed with method. Not meeting relative MVPA and VPA recommendation was associated with significantly higher likelihood for presence of MetS. Since relative intensity is part of the current PA recommendation, it should be considered when assessing population PA and associated health risks in the older adults.

• Stensvold, Dorthe; Sandbakk, Silvana Bucher; Viken, Hallgeir; Zisko, Nina; Reitlo, Line Skarsem & Nauman, Javaid [Show all 18 contributors for this article] (2017). Cardiorespiratory Reference Data in Older Adults: The Generation 100 Study. Medicine & Science in Sports & Exercise. ISSN 0195-9131. 49(11), p. 2206–2215. doi: 10.1249/MSS.0000000000001343. Full text in Research Archive Show summary

  Purpose: Cardiorespiratory fitness (CRF) is regarded a clinical vital sign, and accurate reference values for all age groups are essential. Little data exist on CRF and cardiorespiratory function in older adults. The aim of this study was to provide normative values for CRF and cardiorespiratory function in older adults, including people with history of cardiovascular diseases (CVD). Methods: In total, 1537 (769 women) participants age 70 to 77 yr underwent clinical examinations and cardiopulmonary exercise tests. Peak oxygen uptake (V˙ O2peak), ventilation (V˙ Epeak), expiration of carbon dioxide (VV˙ CO2peak), breathing frequency (BFpeak), tidal volume (VTpeak), oxygen pulse (O2 pulsepeak), ventilatory efficiency (EqV˙ O2peak and EqV˙ CO2peak), and 1-min HR recovery were assessed. Results: Men compared with women had higher V˙ O2peak (31.3 T 6.7 vs 26.2 T 5.0 mLIminj1 Ikgj1 ), BFpeak (41.8 T 8.0 vs 39.7 T 7.1 breaths per minute), VTpeak (2.3 T 0.5 vs 1.6 T 0.3), O2 pulsepeak (16.4 T 3.2 vs 11.3 T 2.0), V˙ CO2peak (2.9 T 0.2 and 1.9 T 0.1 LIminj1 ), V˙ Epeak (96.2 T 21.7 vs 61.1 T 21.6 LIminj1 ), EqV˙ O2peak (38.0 T 6.9 vs 35.1 T 5.6), and EqV˙ CO2peak (33.5 T 5.7 vs 31.9 T 4.5). Women and men with CVD had lower V˙ O2peak (14% and 19%), peak HR (5% and 6%), V˙ Epeak (8% and 10%), VTpeak (7% and 4%), and lower EqV˙ CO2peak (4% and 6%) compared with their healthy counterparts, respectively. Compared with healthy women and men, 1-min HR recovery was 12% and 16% lower for women and men with CVD. Conclusions: This study represents the largest reference material on directly measured CRF and cardiorespiratory function in older men and women, with and without CVD. This novel information will help researchers and clinicians to interpret data form cardiopulmonary testing in older adults.

• Sandbakk, Silvana Bucher; Nauman, Javaid; Lavie, Carl J.; Wisløff, Ulrik & Stensvold, Dorthe (2017). Combined Association of Cardiorespiratory Fitness and Body Fatness With Cardiometabolic Risk Factors in Older Norwegian Adults: The Generation 100 Study. Mayo Clinic Proceedings: Innovations, Quality & Outcomes (MCP:IQ&O). 1(1). doi: 10.1016/j.mayocpiqo.2017.05.001. Full text in Research Archive Show summary

  Objective To investigate the independent and combined associations of fitness and fatness with cardiometabolic risk factors in older Norwegian women and men. Patients and Methods We conducted a cross-sectional study of 505 women and 417 men aged 70 to 77 years enrolled in the Generation 100 study in Norway. Fitness was assessed as peak oxygen uptake and fatness as high body mass index (BMI; ≥25 kg/m2), waist circumference (WC) of 88 cm or greater for women and 102 cm or greater for men, and percent body fat (%BF) of 35% or greater and 25% or greater for women and men, respectively. High cardiometabolic risk was defined as the presence of 2 or more of the following risk factors: elevated triglyceride level, reduced high-density lipoprotein cholesterol concentration, elevated blood pressure, and elevated fasting glucose level or pharmacological treatment of these conditions. Results Receiver operating characteristic curve analyses identified fitness levels of less than 25.7 and less than 30.7 mL/kg per minute in women and men, respectively, as critical thresholds for having high cardiometabolic risk. Individuals with levels below these thresholds had an adjusted odds ratio of 2.77 (95% CI, 2.09-3.66) for having high cardiometabolic risk, while high BMI, WC, and %BF had odds ratios (95% CIs) of 3.58 (2.69-4.77), 3.06 (2.29-4.10), and 3.26 (2.47-4.30), respectively. In our combined analyses, being lean did not attenuate the cardiometabolic risk associated with low fitness, and combinations of low fitness and/or high BMI, WC, or %BF cumulatively increased cardiometabolic risk. Conclusion Low fitness and indication of fatness were independently and cumulatively associated with poor cardiometabolic health. Our results emphasize the importance of including both physical fitness and body fatness in the assessment of cardiometabolic risk and health promotion efforts in older adults.

• Zisko, Nina; Skjerve, Kjerstin Næss; Tari, Atefe R; Sandbakk, Silvana Bucher; Wisløff, Ulrik & Nes, Bjarne [Show all 7 contributors for this article] (2017). Personal Activity Intelligence (PAI), sedentary behavior and cardiovascular risk factor clustering - the HUNT study. Progress in cardiovascular diseases. ISSN 0033-0620. 60(1), p. 89–95. doi: 10.1016/j.pcad.2017.02.007. Full text in Research Archive
• Sandbakk, Silvana Bucher; Nauman, Javaid; Zisko, Nina; Sandbakk, Øyvind; Aspvik, Nils Petter & Stensvold, Dorthe [Show all 7 contributors for this article] (2016). Sedentary Time, Cardiorespiratory Fitness, and Cardiovascular Risk Factor Clustering in Older Adults--the Generation 100 Study. Mayo Clinic proceedings. ISSN 0025-6196. 91(11), p. 1525–1534. doi: 10.1016/j.mayocp.2016.07.020. Full text in Research Archive
• Sandbakk, Silvana Bucher; Sandbakk, Øyvind; Peacock, Oliver; James, Philip; Welde, Boye & Stokes, Keith [Show all 8 contributors for this article] (2015). Effects of acute supplementation of L-arginine and nitrate on endurance and sprint performance in elite athletes. Nitric oxide. ISSN 1089-8603. 48, p. 10–15. doi: 10.1016/j.niox.2014.10.006. Full text in Research Archive
• Sandbakk, Øyvind; Sandbakk, Silvana Bucher; Supej, Matej & Holmberg, Hans-Christer (2014). The velocity and energy profiles of elite cross-country skiers executing downhill turns with different radii. International Journal of Sports Physiology and Performance (IJSPP). ISSN 1555-0265. 9(1), p. 41–47. doi: 10.1123/IJSPP.2013-0383. Full text in Research Archive
• Sandbakk, Øyvind; Spencer, Matthew; Ettema, Gerardus Johannes C; Bucher, Silvana Andrea; Skovereng, Knut & Welde, Boye (2014). The Physiology and Biomechanics of Upper-Body Repeated Sprints in Ice Sledge Hockey. International Journal of Sports Physiology and Performance (IJSPP). ISSN 1555-0265. 9(1), p. 77–84. doi: 10.1123/IJSPP.2012-0355. Full text in Research Archive Show summary

  PURPOSE: To investigate performance and the associated physiological and biomechanical responses during upper-body repeated sprint work. METHODS: Twelve male ice sledge hockey players from the Norwegian national team performed eight 30-m sprints with start every 30 s and an active recovery between sprints. Time was captured every 10 m by photocells, cycle length and rate were determined by video analyses, and heart rate and blood lactate concentration were measured by conventional methods. RESULTS: The percent sprint decrement was 7% over the eight trials, with significant reductions in performances from the previous trial already on the second trial (all P<0.05). Furthermore, cycle rate was reduced by 9% over the eight trials (P<0.05). Similar changes in performance and kinematic patterns were evident for all 10-m phases of the sprints. Heart rate gradually increased to 94% of maximal (178±10 beats/min) over the eight trials, and the mean reductions in heart rate was 7±2 beats/min during the 22-24 s of active recovery for all trials (all P<0.05). The blood lactate concentration increased to the athletes' maximal levels over the eight sprints (P<0.05). CONCLUSIONS: This is the first study to investigate performance, physiological and biomechanical aspects of self propulsed upper-body repeated sprint work. The observed sprint decrement over the eight trials was associated with reductions in cycle rates and high physiological demands. However, no kinematic and physiological characteristics were significantly correlated to repeated sprint ability or the sprint decrement.

• Sandbakk, Silvana Bucher; Supej, Matej; Sandbakk, Øyvind & Holmberg, Hans-Christer (2013). Downhill turn techniques and associated physical characteristics in cross-country skiers. Scandinavian Journal of Medicine & Science in Sports. ISSN 0905-7188. 24(4), p. 708–716. doi: 10.1111/sms.12063. Full text in Research Archive Show summary

  Three dominant techniques are used for downhill turning in cross-country skiing. In this study, kinematic, kinetic, and temporal characteristics of these techniques are described and related to skier strength and power. Twelve elite female cross-country skiers performed six consecutive turns of standardized geometry while being monitored by a Global Navigation Satellite System. Overall time was used as an indicator of performance. Skiing and turning parameters were determined from skier trajectories; the proportional use of each technique was determined from video analysis. Leg strength and power were determined by isometric squats and countermovement jumps on a force plate. Snow plowing, parallel skidding, and step turning were utilized for all turns. Faster skiers employed less snow plowing and more step turning, more rapid deceleration and earlier initiation of step turning at higher speed (r = 0.80–0.93; all P < 0.01). Better performance was significantly correlated to higher mean speed and shorter trajectory (r = 0.99/0.65; both P < 0.05) and to countermovement jump characteristics of peak force, time to peak force, and rate of force development (r = −0.71/0.78/−0.83; all P < 0.05). In conclusion, faster skiers used step turning to a greater extent and exhibited higher maximal leg power, which enabled them to combine high speeds with shorter trajectories during turns.

• Sandbakk, Silvana Bucher; Sandbakk, Øyvind; Peacock, Oliver; James, Philip; Wisløff, Ulrik & Tjønna, Arnt Erik (2013). Effects of Combined Supplementation of Dietary Nitrate and L-arginine on Physiological Responses, Sprint and Endurance. In Balagué, N.; Torrents, C.; Villanova, A.; Cadefau, J.; Tarragó, R. & Tsolakidis, E. (Ed.), Book of Abstracts.18th annual Congress of the European College of Sport Science. 26th - 29th June, Barcelona - Spain. European College of Sport Science. ISSN 9788469577868. doi: 10.1016/j.niox.2014.10.006. Full text in Research Archive
• Sandbakk, Øyvind; Sandbakk, Silvana Bucher; Ettema, Gerardus Johannes C & Welde, Boye (2013). Effects of Intensity and Duration in Aerobic High-Intensity Interval Training in Highly Trained Junior Cross-Country Skiers. Journal of Strength and Conditioning Research. ISSN 1064-8011. 27(7), p. 1974–1980. doi: 10.1519/JSC.0b013e3182752f08. Full text in Research Archive Show summary

  The purpose of this study was to test whether a long duration of aerobic high-intensity interval training is more effective than shorter intervals at a higher intensity in highly trained endurance athletes. The sample comprised of 12 male and 9 female, national level junior cross-country skiers (age: 17.5±0.4 yr, maximal oxygen uptake (VO2max): 67.4±7.7 mL min-1 kg-1), who performed 8-week baseline and 8-week intervention training periods on dry land. During the intervention period, a short-interval group (n=7) added two weekly sessions with short duration intervals (2- to 4-min bouts, total duration of 15- 20 min), a long-interval group (n=7) added two weekly sessions with long duration intervals (5- to 10- min bouts, total duration of 40-45 min). The interval sessions were performed with the athletes’ maximal sustainable intensity. A control group (n=7) added two weekly sessions with low-intensity endurance training at 65-74% of maximal heart rate. Before and after the intervention period, the skiers were tested for time-trial performance on 12 km roller-ski skating and 7 km hill run. VO2max and oxygen uptake at the ventilatory threshold (VO2VT) were measured during treadmill running. After the intervention training period, the long-interval group improved 12 km roller-ski, 7 km hill run, VO2max and VO2VT by 6.8±4.0%, 4.8±2.6%, 3.7±1.6% and 5.8±3.3%, respectively, from pre to post-testing, and improved both performance tests and VO2VT when compared to the short-interval group and the control group (all p<0.05). The short-interval group improved VO2max by 3.5±3.2% from pre to post-testing (p<0.05), whereas the control group remained unchanged. As hypothesized, a long duration of aerobic high-intensity interval training improved endurance performance and oxygen uptake at the ventilatory threshold more than shorter intervals at a higher intensity.

• Sandbakk, Øyvind; Sandbakk, Silvana Bucher; Skovereng, Knut; Welde, Boye & Ettema, Gerardus Johannes C (2012). The Physiology of World Class Sledge Ice-Hockey. In Meeusen, R; Duchateau, J; Roelands, B; Klass, M; Geus, B De; Baudry, S & Tsolakidis, E (Ed.), 17th annual Congress of the ECSS. BlosoVlaamseoverheid. ISSN 9789090268682. Full text in Research Archive
• Sandbakk, Silvana Bucher; Supej, Matej; Sandbakk, Øyvind & Holmberg, HC (2012). Downhill Turn Techniques and Performance in Cross-Country Skiing: Associations with Mechanical and Physical Parameters. In Meeusen, R; Duchateau, J; Roelands, B; Klass, M; Geus, B De; Baudry, S & Tsolakidis, E (Ed.), 17th annual Congress of the ECSS. BlosoVlaamseoverheid. ISSN 9789090268682. p. 241–241. Full text in Research Archive
• Sandbakk, Silvana Bucher; Supej, Matej; Sandbakk, Øyvind & Holmberg, HC (2012). Mechanical Parameters as Predictors of Downhill Turn Performance in Cross-Country Skiing. In Hakkarainen, A; Lindinger, S & Linnamo, Vesa (Ed.), 2nd International Congress of Science and Nordic Skiing. Congress Proceedings. University of Jyväskylä. ISSN 9789513947361. p. 67–67. Full text in Research Archive
• Sandbakk, Øyvind; Sandbakk, Silvana Bucher; Ettema, Gerardus Johannes C & Welde, Boye (2012). Effects of intensity and duration in aerobic high-intensity interval training. In Hakkarainen, A; Lindinger, S & Linnamo, Vesa (Ed.), 2nd International Congress of Science and Nordic Skiing. Congress Proceedings. University of Jyväskylä. ISSN 9789513947361. p. 99–99. doi: 10.1519/jsc.0b013e3182752f08. Full text in Research Archive

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• Sandbakk, Øyvind Bucher; Tønnessen, Espen; Sandbakk, Silvana Bucher & Haugen, Thomas André (2025). Training Philosophy: What Is It, and What Are the Main Components? International Journal of Sports Physiology and Performance (IJSPP). ISSN 1555-0265. 20(1), p. 1–1. doi: 10.1123/ijspp.2024-0473. Full text in Research Archive
• Skorski, Sabrina & Sandbakk, Silvana Bucher (2024). Gender Equity in Sport-Science Academia: We Still Have a Long Way to Go! International Journal of Sports Physiology and Performance (IJSPP). ISSN 1555-0265. 19(9), p. 849–850. doi: 10.1123/ijspp.2024-0279. Full text in Research Archive
• Gjølme, Egil Galaaen; Sandbakk, Silvana Bucher & Hagen, Ruben Vist (2024). Svømme- og livredningsopplæring i LK20 - fagdidaktiske anbefalinger basert på drukningsstatistikk fra perioden 1988 - 2023. Full text in Research Archive
• Talsnes, Rune Kjøsen; Tønnessen, Espen; Sandbakk, Silvana Bucher; Haugen, Thomas André & Sandbakk, Øyvind Bucher (2024). Early warning signs, monitoring tools, and actions taken by world-class endurance coaches in cases of underperformance. Full text in Research Archive
• Talsnes, Rune Kjøsen; Tønnessen, Espen; Sandbakk, Silvana Bucher; Haugen, Thomas André & Sandbakk, Øyvind Bucher (2024). Verktøy for belastningsstyring og tiltak ved overtrening benyttet av suksessfulle norske trenere i typiske utholdenhetsidretter. Full text in Research Archive
• Haugen, Tommy; Tønnessen, Espen; Sandbakk, Silvana Bucher & Sandbakk, Øyvind Bucher (2023). Training Quality-An Unexplored Domain in Sport Science. International Journal of Sports Physiology and Performance (IJSPP). ISSN 1555-0265. 18(3), p. 221–222. doi: 10.1123/ijspp.2022-0500. Full text in Research Archive
• Sandbakk, Silvana Bucher; Haugen, Thomas André; Tønnessen, Espen; Losnegard, Thomas Johansen & Sandbakk, Øyvind Bucher (2023). Training practices and coaching philosophy of successful Norwegian national coaches in endurance sports. Full text in Research Archive
• Sandbakk, Øyvind Bucher; Sandbakk, Silvana Bucher; Tønnessen, Espen; Losnegard, Thomas Johansen; Seiler, Stephen & Haugen, Thomas André (2023). Training for Olympic gold in endurance sports: views from successful coaches. Full text in Research Archive
• Sandbakk, Silvana Bucher; Walther, Jacob; Solli, Guro Strøm; Tønnessen, Espen & Haugen, Thomas (2023). Training Quality-What Is It and How Can We Improve It? International Journal of Sports Physiology and Performance (IJSPP). ISSN 1555-0265. 18(5), p. 557–560. doi: 10.1123/ijspp.2022-0484. Full text in Research Archive Show summary

  Purpose: The concept of training quality reflects that the effect of training is dependent on more than the mere product of training load (eg, duration, intensity, frequency). The aims of this commentary are to (1) propose a practice-oriented framework to describe training quality and its general and context-dependent characteristics and (2) discuss how athletes and coaches can work to improve training quality. Conclusions: Training quality can be viewed from different perspectives. The holistic dimension includes the entire training process (goal setting, gap analysis, application of training principles and methods, etc), while a narrower dimension encompasses the specific training sessions and how they are executed in relation to the intended purpose. To capture the varying contexts, we define training quality as the degree of excellence related to how the training process or training sessions are executed to optimize adaptations and, thereby, improve overall performance. Although training quality is challenging to quantify, we argue that identification and assessment of quality indicators will increase our scientific understanding and consequently help coaches and athletes to improve training quality. We propose that the physical, technical, and psychological factors of training quality can be improved through an individualized learning process of systematic planning, execution, and debriefing. However, assessment tools should be identified and scientifically validated across different training sessions and sports. We encourage further interventions to improve training quality.

• Sandbakk, Silvana Bucher & Gjølme, Egil Galaaen (2022). Svømme og livredningsopplæring i LK20 – fagdidaktiske anbefalinger basert på drukningsstatistikk i Norge i perioden 1988 - 2020. Del 1. Full text in Research Archive
• Gjølme, Egil Galaaen & Sandbakk, Silvana Bucher (2022). Svømme og livredningsopplæring i LK20 – Fagdidaktiske anbefalinger basert på drukningsstatistikk i Norge i perioden 1988 - 2020. Del 2. Full text in Research Archive
• Johansen, Kristoffer Robin; Ranhoff, Anette Hylen; Sørensen, Eivind; Nes, Bjarne; Sandbakk, Silvana Bucher & Wilsgaard, Tom [Show all 10 contributors for this article] (2022). Ten-year mortality among older male recreational endurance athletes in the Birkebeiner Ageing Study in comparison with older men from the Tromsø Study. Full text in Research Archive
• Sandbakk, Silvana Bucher (2022). Langrenn som treningsform. [Journal]. vi.no. Full text in Research Archive
• Sandbakk, Silvana Bucher (2022). Science and best practice in cross-country skiing. Full text in Research Archive
• Gjølme, Egil Galaaen & Sandbakk, Silvana Bucher (2022). Svømme- og livredningsopplæring i LK20. Fagdidaktiske anbefalinger basert på drukningsstatistikk i perioden 1988 - 2021. Full text in Research Archive
• Gjølme, Egil Galaaen & Sandbakk, Silvana Bucher (2022). Drowning Statistics and Didactical Implications for Education. Full text in Research Archive
• Johansen, Kristoffer Robin; Ranhoff, Anette Hylen; Sørensen, Eivind; Nes, Bjarne; Heitmann, Kim Arne & Apelland, Turid [Show all 12 contributors for this article] (2022). Risk of atrial fibrillation and stroke among older men exposed to prolonged endurance sport practice – a 10-year follow-up. The Birkebeiner Ageing Study and the Tromsø Study. Full text in Research Archive
• Johansen, Kristoffer Robin; Ranhoff, Anette Hylen; Sørensen, Eivind; Nes, Bjarne; Heitmann, Kim Arne & Apelland, Turid [Show all 12 contributors for this article] (2022). Risk of atrial fibrillation and stroke among older men exposed to prolonged endurance sport practice - a 10-year follow-up. The Birkebeiner Ageing Study and the Tromsø Study. Full text in Research Archive
• Sandbakk, Silvana Bucher (2019). Trening i godt voksen alder viktigere enn da du var 20. [Journal]. Dagbladet. Full text in Research Archive
• Sandbakk, Silvana Bucher (2019). Hjerteinfarkt - Viktig trening. [Journal]. Pensjonisten. Full text in Research Archive
• Sandbakk, Silvana Bucher (2019). Kan det å være sprek kompensere for overvekt? Ny studie overrasker. [Journal]. Aftenposten. Full text in Research Archive
• Sandbakk, Silvana Bucher (2019). Slik bedrer du hjertehelsa. [Journal]. Dagbladet. Full text in Research Archive
• Sandbakk, Silvana Bucher (2019). Fremtidens muligheter: Digitale løsninger. Full text in Research Archive
• Sandbakk, Silvana Bucher (2019). Fire eksperter og én mosjonist gir deg sine beste løpetips. [Internet]. Adresseavisen/Aftenposten - Podcast. Full text in Research Archive
• Sandbakk, Silvana Bucher (2019). Det er ikke for seint å begynne. [Journal]. Dagbladet. Full text in Research Archive
• Sandbakk, Silvana Bucher (2019). Trening i sesong. [Journal]. Skisport. Full text in Research Archive
• Sandbakk, Silvana Bucher (2018). Kondisjon, stillesitting og hjertehelse hos eldre. Full text in Research Archive
• Viken, Hallgeir; Sandbakk, Silvana Bucher & Stensvold, Dorthe (2017). Sammenhengen mellom god kondisjon og hjertehelse hos eldre. Full text in Research Archive
• Sandbakk, Silvana Bucher (2016). Does it matter how long you sit—if you are fit? [Internet]. http://geminiresearchnews.com/2016/10/matter-long-sit-fit/. Full text in Research Archive
• Sandbakk, Silvana Bucher; Nauman, Javaid; Zisko, Nina; Sandbakk, Øyvind; Aspvik, Nils Petter & Stensvold, Dorthe [Show all 7 contributors for this article] (2016). High Age-specific Cardiorespiratory Fitness Attenuates the Adverse Effect of Sedentary Time on Cardiovascular Risk Factor Clustering in Older Adults: The Generation 100 Study. Full text in Research Archive
• Sandbakk, Silvana Bucher (2016). Er stillesitting farlig hvis du har god kondis? [Internet]. http://gemini.no/2016/11/stillesitting-farlig-kondis/. Full text in Research Archive
• Sandbakk, Silvana Bucher (2015). Når det ikke funker... Full text in Research Archive
• Sandbakk, Silvana Bucher (2015). High Cardiorespiratory Fitness Attenuates the Adverse Effect of Prolonged Sedentary Time on the Prevalence of Metabolic Syndrome in Older Adults: The Generation 100 Study. Full text in Research Archive
• Sandbakk, Silvana Bucher (2015). Generasjon 100. Full text in Research Archive
• Sandbakk, Silvana Bucher; Holmberg, Hans-Christer; Supej, Matej & Sandbakk, Øyvind (2014). Downhill turn techniques and associated physical characteristics in cross-country skiers. Full text in Research Archive
• Sandbakk, Øyvind; Sandbakk, Silvana Bucher; Ettema, Gerardus Johannes C & Welde, Boye (2014). Effects of intensity and duration in aerobic high-intensity interval training. Full text in Research Archive
• Sandbakk, Silvana Bucher & Stensvold, Dorthe (2013). Dette skal gi dem et lengre og friskere liv. [Internet]. Bergens Tidende. Full text in Research Archive
• Bucher, Silvana Andrea (2013). Seig opp og ung ned. [Internet]. Dagens Næringsliv. Full text in Research Archive
• Bucher, Silvana Andrea (2013). Hockey: to ulike strategier. [Journal]. Dagens Næringsliv. Full text in Research Archive
• Bucher, Silvana Andrea (2013). Får 70-åringer til å springe på seg melkesyre. [Internet]. Dagens Næringsliv. Full text in Research Archive
• Sandbakk, Silvana Bucher; Sandbakk, Øyvind; Peacock, Oliver; James, Philip; Wisløff, Ulrik & Tjønna, Arnt Erik (2013). Effects of Combined Supplementation of Dietary Nitrate and L-arginine on Physiological Responses, Sprint and Endurance. Full text in Research Archive
• Sandbakk, Silvana Bucher (2013). Dette skal gi dem et lengre og friskere liv. [Journal]. Adresseavisen. Full text in Research Archive
• Sandbakk, Øyvind; Sandbakk, Silvana Bucher; Skovereng, Knut; Welde, Boye & Ettema, Gerardus Johannes C (2012). The Physiology of World Class Sledge Ice-Hockey. Full text in Research Archive
• Sandbakk, Øyvind; Sandbakk, Silvana Bucher; Ettema, Gerardus Johannes C & Welde, Boye (2012). Effects of intensity and duration in aerobic high-intensity interval training. Full text in Research Archive
• Sandbakk, Silvana Bucher; Supej, Matej; Sandbakk, Øyvind & Holmberg, HC (2012). Mechanical Parameters as Predictors of Downhill Turn Performance in Cross-Country Skiing. Full text in Research Archive
• Sandbakk, Silvana Bucher & Stensvold, Dorthe (2012). Generasjon 100 - Trening som medisin for eldre. Norsk idrettsmedisin. ISSN 0806-9328. p. 7–9. Full text in Research Archive
• Sandbakk, Silvana Bucher (2012). Den vanskelige langrennssvingen. [TV]. NRK Schrödingers Katt. Full text in Research Archive
• Sandbakk, Silvana Bucher; Supej, Matej; Sandbakk, Øyvind & Holmberg, HC (2012). Downhill Turn Techniques and Performance in Cross-Country Skiing: Associations with Mechanical and Physical Parameters. Full text in Research Archive
• Sandbakk, Øyvind Bucher & Sandbakk, Silvana Bucher (2022). Online course L1.12: Physiological determinants of biathlon performance. IBU Academy, International Biathlon Union. Full text in Research Archive
• Sandbakk, Silvana Bucher & Sandbakk, Øyvind Bucher (2022). Online course L1.10: Growth and development physiology. IBU Academy, International Biathlon Union. Full text in Research Archive
• Sandbakk, Øyvind Bucher & Sandbakk, Silvana Bucher (2022). Online course B.9: Anatomical structures and physiological functions. IBU Academy, International Biathlon Union. Full text in Research Archive

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