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Potolitsyna N, Parshukova O, Vakhnina N, Alisultanova N, Kalikova L, Tretyakova A, Chernykh A, Shadrina V, Duryagina A, Bojko E. Lactate thresholds and role of nitric oxide in male rats performing a test with forced swimming to exhaustion. Physiol Rep 2023; 11:e15801. [PMID: 37667373 PMCID: PMC10477198 DOI: 10.14814/phy2.15801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Revised: 08/10/2023] [Accepted: 08/14/2023] [Indexed: 09/06/2023] Open
Abstract
The present study assessed a complex of biochemical parameters at the anaerobic threshold (AT) in untrained male Wistar rats with different times to exhaustion (Tex ) from swimming. The first group of rats was randomly divided into six subgroups and subjected to a swimming test to exhaustion without a load or with a load of 2%-10% of body weight (BW). In the first group, we established that for untrained rats, the load of 4% BW in the swimming to exhaustion test was optimal for endurance assessment in comparison with other loads. The second group of rats went through a preliminary test with swimming to exhaustion at 4% BW and was then divided into two subgroups: long swimming time (LST, Tex > 240 min) and short swimming time (SST, Tex < 90 min). All rats of the second group performed, for 6 days, an experimental training protocol: swimming for 20 min each day with weight increasing each day. We established that the AT was 3% BW in SST rats and 5% BW in LST rats. The AT shifted to the right on the lactate curve in LST rats. Also, at the AT in the LST rats, we found significantly lower levels of blood lactate, cortisol, and NO.
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Affiliation(s)
- Natalya Potolitsyna
- Institute of Physiology of Kоmi Science Centre of the Ural Branch of the Russian Academy of Sciences, FRC Komi SC UB RASSyktyvkarRussia
| | - Olga Parshukova
- Institute of Physiology of Kоmi Science Centre of the Ural Branch of the Russian Academy of Sciences, FRC Komi SC UB RASSyktyvkarRussia
| | - Nadezhda Vakhnina
- Institute of Physiology of Kоmi Science Centre of the Ural Branch of the Russian Academy of Sciences, FRC Komi SC UB RASSyktyvkarRussia
| | - Nadezhda Alisultanova
- Institute of Physiology of Kоmi Science Centre of the Ural Branch of the Russian Academy of Sciences, FRC Komi SC UB RASSyktyvkarRussia
| | - Lubov Kalikova
- Institute of Physiology of Kоmi Science Centre of the Ural Branch of the Russian Academy of Sciences, FRC Komi SC UB RASSyktyvkarRussia
| | - Anastasia Tretyakova
- Institute of Physiology of Kоmi Science Centre of the Ural Branch of the Russian Academy of Sciences, FRC Komi SC UB RASSyktyvkarRussia
| | - Alexey Chernykh
- Institute of Physiology of Kоmi Science Centre of the Ural Branch of the Russian Academy of Sciences, FRC Komi SC UB RASSyktyvkarRussia
| | - Vera Shadrina
- Institute of Physiology of Kоmi Science Centre of the Ural Branch of the Russian Academy of Sciences, FRC Komi SC UB RASSyktyvkarRussia
| | - Arina Duryagina
- Institute of Physiology of Kоmi Science Centre of the Ural Branch of the Russian Academy of Sciences, FRC Komi SC UB RASSyktyvkarRussia
| | - Evgeny Bojko
- Institute of Physiology of Kоmi Science Centre of the Ural Branch of the Russian Academy of Sciences, FRC Komi SC UB RASSyktyvkarRussia
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Modeling lactate threshold in young squad athletes: influence of sex, maximal oxygen uptake, and cost of running. Eur J Appl Physiol 2023; 123:573-583. [PMID: 36411398 PMCID: PMC9941268 DOI: 10.1007/s00421-022-05084-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Accepted: 10/20/2022] [Indexed: 11/23/2022]
Abstract
PURPOSE This study aimed to investigate: 1. The influence of sex and age on the accuracy of the classical model of endurance performance, including maximal oxygen uptake ([Formula: see text]), its fraction (LT2%), and cost of running (CR), for calculating running speed at lactate threshold 2 (vLT2) in young athletes. 2. The impact of different CR determination methods on the accuracy of the model. 3. The contributions of [Formula: see text], LT2%, and CR to vLT2 in different sexes. METHODS 45 male and 55 female young squad athletes from different sports (age: 15.4 ± 1.3 years; [Formula: see text]: 51.4 ± 6.8 [Formula: see text]) performed an incremental treadmill test to determine [Formula: see text], LT2%, CR, and vLT2. CR was assessed at a fixed running speed (2.8 [Formula: see text]), at lactate threshold 1 (LT1), and at 80% of [Formula: see text], respectively. RESULTS Experimentally determined and modeled vLT2 were highly consistent independent of sex and age (ICC [Formula: see text] 0.959). The accuracy of vLT2 modeling was improved by reducing random variation using individualized CR at 80% [Formula: see text] (± 4%) compared to CR at LT1 (± 7%) and at a fixed speed (± 8%). 97% of the total variance of vLT2 was explained by [Formula: see text], LT2%, and CR. While [Formula: see text] and CR showed the highest unique (96.5% and 31.9% of total [Formula: see text], respectively) and common (- 31.6%) contributions to the regression model, LT2% made the smallest contribution (7.5%). CONCLUSION Our findings indicate: 1. High accuracy of the classical model of endurance performance in calculating vLT2 in young athletes independent of age and sex. 2. The importance of work rate selection in determining CR to accurately predict vLT2. 3. The largest contribution of [Formula: see text] and CR to vLT2, the latter being more important in female athletes than in males, and the least contribution of LT2%.
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Johansen JM, Sunde A, Helgerud J, Støren Ø. Relationships Between Maximal Aerobic Speed, Lactate Threshold, and Double Poling Velocity at Lactate Threshold in Cross-Country Skiers. Front Physiol 2022; 13:829758. [PMID: 35295565 PMCID: PMC8918826 DOI: 10.3389/fphys.2022.829758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Accepted: 01/31/2022] [Indexed: 11/13/2022] Open
Abstract
Purpose To investigate the relationships between maximal aerobic speed (MAS), lactate threshold in per cent of peak oxygen uptake (LT) and velocity at LT (LTv) in cross-country skiers. Secondly, we aimed to explore the fit of an equation previously used in cyclists and runners in a cohort of well-trained, competitive cross-country skiers for calculation of LTv. Thirdly, we aimed to investigate if a new LTv could still be calculated after a period of regular training only by providing a new MAS. Methods Ninety-five competitive cross-country skiers (65 males and 30 females) were tested for maximal oxygen uptake (VO2max), peak oxygen uptake in double poling (DP-VO2peak), oxygen cost of double poling (CDP), LT, and LTv. Thirty-five skiers volunteered to be tested 3 months later to evaluate potential changes in LT and LTv. Results Velocity at LT was mainly determined by MAS (r = 0.88, p < 0.01). LT did not show a significant impact on LTv. The product of MAS·LT precisely predicted LTv at baseline (r = 0.99, SEE = 2.4%), and by only measuring MAS, a new LTv could be accurately calculated (r = 0.92, SEE = 6.8%) 3 months later in a sub-set of the initial 95 skiers (n = 35). Conclusion The results suggest that LT has minor impact on LTv in DP tested in a laboratory. LTv seemed to be predominantly determined by MAS, and we suggest to put more focus on MAS and less on LT and LTv in regular testing to evaluate aerobic performance capacity in DP.
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Affiliation(s)
- Jan-Michael Johansen
- Department of Sports, Physical Education and Outdoor Studies, University of Southeastern Norway, Bø, Norway
- *Correspondence: Jan-Michael Johansen,
| | - Arnstein Sunde
- Department of Sports, Physical Education and Outdoor Studies, University of Southeastern Norway, Bø, Norway
| | - Jan Helgerud
- Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway
- Myworkout, Medical Rehabilitation Center, Trondheim, Norway
| | - Øyvind Støren
- Department of Sports, Physical Education and Outdoor Studies, University of Southeastern Norway, Bø, Norway
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Sunde A, Christoffersen F, Johansen JM, Støren Ø. Steeper or Faster? Tactical Dispositions to Minimize Oxygen Cost in Ski Mountaineering. Front Sports Act Living 2022; 3:828389. [PMID: 35174324 PMCID: PMC8841821 DOI: 10.3389/fspor.2021.828389] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Accepted: 12/30/2021] [Indexed: 11/13/2022] Open
Abstract
Purpose Investigate the effect of speed, inclination, and use of heel elevator on the oxygen cost of vertical climbing (Cvert) in ski mountaineering. Methods In this study, 19 participants who were (3 women and 16 men) moderate- to well-trained recreational Norwegian ski mountaineers were involved. All participants were tested for VO2max in running, and in a ski mountaineering test on a treadmill, to assess Cvert. The test protocol consisted of 12 4 min work periods at different inclinations from 13 to 23°, with continuous VO2 measurements. After every second work period, the inclination increased by 2°, and speed was decreased accordingly. The speed reduction was based on the equation Vvert = speed · sin(α), where α represents the angle of inclination. Vvert was thus held constant for each work period (854 m·h−1). All work periods were completed twice, with and without a heel elevator. Half of the subjects started with the smallest inclination, and the other half started with the steepest inclination. Results The results showed that Cvert was unchanged at all inclinations except 13°, where there was a significantly higher Cvert, at the same Vvert. Only at 13°, Cvert was higher with the use of heel elevator. There was also a significant trend indicating lower Cvert with use of heel elevator with steeper inclination. Conclusions There seemed to be nothing to gain by choosing detours if the inclination was 13° or less. The use of heel elevator was more advantageous, the steeper the inclination, but at 13° there was a negative effect of using heel elevator.
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Støa EM, Helgerud J, Rønnestad BR, Hansen J, Ellefsen S, Støren Ø. Factors Influencing Running Velocity at Lactate Threshold in Male and Female Runners at Different Levels of Performance. Front Physiol 2020; 11:585267. [PMID: 33250778 PMCID: PMC7672120 DOI: 10.3389/fphys.2020.585267] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Accepted: 10/08/2020] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND The primary aim was to examine the relationship between lactate threshold (LT) expressed as percentage of maximal oxygen uptake (VO2max) and running velocity at LT (LTV). A secondary aim was to investigate to what extent VO2max, oxygen cost of running (CR), and maximal aerobic speed (MAS) determined LTV. A third aim was to investigate potential differences in LT and LTV between elite, national and recreational runners, as well as possible gender differences regarding VO2max, CR, LT, and LTV. METHODS Seventy-five competitive runners (37 males and 38 females) with an average VO2max of 63.0 ± 9.3 mL⋅kg-1⋅min-1, and an average LTV of 13.6 ± 2.3 km⋅h-1 were tested for VO2max, LT, LTV, MAS, and CR. RESULTS Lactate threshold did not correlate with LTV. With an r - value of 0.95 (p < 0.001) and a standard error of estimate of 4.0%, the product of MAS and individual LT determined 90% of LTV, outside a range of ±0.27 km⋅h-1. LTV increased with higher performance level. However, LT did not differ between elite, national and recreational runners. Female runners had 2.5% higher LT, 8% lower LTV, and 21% lower VO2max, but 9% better CR than male runners. CONCLUSION Lactate threshold did not correlate with LTV. The product of MAS and LT correlated strongly with LTV. There were no differences between elite, national and recreational runners regarding LT, but female runners had higher LT than the male runners. Female runners at the same relative performance level had lower LTV and VO2max, but better CR than male runners.
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Affiliation(s)
- Eva Maria Støa
- Department of Sports, Physical Education and Outdoor Studies, University of South-Eastern Norway, Bø, Norway
| | - Jan Helgerud
- Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway
- Myworkout, Medical Rehabilitation Clinic, Trondheim, Norway
| | - Bent R. Rønnestad
- Section for Health and Exercise Physiology, Institute of Public Health and Sport Sciences, Inland Norway University of Applied Sciences, Lillehammer, Norway
| | - Joar Hansen
- Section for Health and Exercise Physiology, Institute of Public Health and Sport Sciences, Inland Norway University of Applied Sciences, Lillehammer, Norway
| | - Stian Ellefsen
- Section for Health and Exercise Physiology, Institute of Public Health and Sport Sciences, Inland Norway University of Applied Sciences, Lillehammer, Norway
| | - Øyvind Støren
- Department of Sports, Physical Education and Outdoor Studies, University of South-Eastern Norway, Bø, Norway
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Johansen JM, Goleva-Fjellet S, Sunde A, Gjerløw LE, Skeimo LA, Freberg BI, Sæbø M, Helgerud J, Støren Ø. No Change - No Gain; The Effect of Age, Sex, Selected Genes and Training on Physiological and Performance Adaptations in Cross-Country Skiing. Front Physiol 2020; 11:581339. [PMID: 33192589 PMCID: PMC7649780 DOI: 10.3389/fphys.2020.581339] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Accepted: 10/02/2020] [Indexed: 01/27/2023] Open
Abstract
The aim was to investigate the effect of training, sex, age and selected genes on physiological and performance variables and adaptations before, and during 6 months of training in well-trained cross-country skiers. National-level cross-country skiers were recruited for a 6 months observational study (pre - post 1 - post 2 test). All participants were tested in an outside double poling time trial (TTDP), maximal oxygen uptake in running (RUN-VO2max), peak oxygen uptake in double poling (DP-VO2peak), lactate threshold (LT) and oxygen cost of double poling (CDP), jump height and maximal strength (1RM) in half squat and pull-down. Blood samples were drawn to genetically screen the participants for the ACTN3 R577X, ACE I/D, PPARGC1A rs8192678, PPARG rs1801282, PPARA rs4253778, ACSL1 rs6552828, and IL6 rs1474347 polymorphisms. The skiers were instructed to train according to their own training programs and report all training in training diaries based on heart rate measures from May to October. 29 skiers completed all testing and registered their training sufficiently throughout the study period. At pre-test, significant sex and age differences were observed in TTDP (p < 0.01), DP-VO2peak (p < 0.01), CDP (p < 0.05), MAS (p < 0.01), LTv (p < 0.01), 1RM half squat (p < 0.01), and 1RM pull-down (p < 0.01). For sex, there was also a significant difference in RUN-VO2max (p < 0.01). No major differences were detected in physiological or performance variables based on genotypes. Total training volume ranged from 357.5 to 1056.8 min per week between participants, with a training intensity distribution of 90-5-5% in low-, moderate- and high-intensity training, respectively. Total training volume and ski-specific training increased significantly (p < 0.05) throughout the study period for the whole group, while the training intensity distribution was maintained. No physiological or performance variables improved during the 6 months of training for the whole group. No differences were observed in training progression or training adaptation between sexes or age-groups. In conclusion, sex and age affected physiological and performance variables, with only a minor impact from selected genes, at baseline. However, minor to no effect of sex, age, selected genes or the participants training were shown on training adaptations. Increased total training volume did not affect physiological and performance variables.
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Affiliation(s)
- Jan-Michael Johansen
- Department of Natural Sciences and Environmental Health, University of South-Eastern Norway, Bø, Norway.,Department of Sports, Physical Education and Outdoor Studies, University of South-Eastern Norway, Bø, Norway
| | - Sannija Goleva-Fjellet
- Department of Natural Sciences and Environmental Health, University of South-Eastern Norway, Bø, Norway
| | - Arnstein Sunde
- Department of Sports, Physical Education and Outdoor Studies, University of South-Eastern Norway, Bø, Norway
| | - Lars Erik Gjerløw
- Department of Sports, Physical Education and Outdoor Studies, University of South-Eastern Norway, Bø, Norway
| | - Lars Arne Skeimo
- Department of Sports, Physical Education and Outdoor Studies, University of South-Eastern Norway, Bø, Norway
| | - Baard I Freberg
- Department of Sports, Physical Education and Outdoor Studies, University of South-Eastern Norway, Bø, Norway.,Landslagslegen.no, Top Sports Medical Office, Tønsberg, Norway.,The Norwegian Biathlon Association, Oslo, Norway
| | - Mona Sæbø
- Department of Natural Sciences and Environmental Health, University of South-Eastern Norway, Bø, Norway
| | - Jan Helgerud
- Department of Circulation and Medical Imaging, Norwegian University of Science and Technology, Trondheim, Norway.,Myworkout, Medical Rehabilitation Centre, Trondheim, Norway
| | - Øyvind Støren
- Department of Sports, Physical Education and Outdoor Studies, University of South-Eastern Norway, Bø, Norway
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Sunde A, Johansen JM, Gjøra M, Paulsen G, Bråten M, Helgerud J, Støren Ø. Stronger Is Better: The Impact of Upper Body Strength in Double Poling Performance. Front Physiol 2019; 10:1091. [PMID: 31507453 PMCID: PMC6716506 DOI: 10.3389/fphys.2019.01091] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Accepted: 08/07/2019] [Indexed: 11/21/2022] Open
Abstract
The purpose of the present study was to compare time results from a roller-skiing double poling (DP) time trial with different physiological variables, muscular strength variables, and DP characteristics in both male and female young competitive skiers with the same relative training background. In order to do this, 28 (16 women and 12 men) well-trained 16–25-year-old cross-country skiers from three Norwegian high schools for skiers, as well as local high performance competitive skiers from the South-East of Norway were recruited to participate in the study. All participants were tested for; maximal oxygen uptake in running, Peak oxygen uptake in DP, lactate threshold in DP, DP economy, time to voluntary exhaustion in DP, force analyses in DP, one repetition maximum and power output in pulldown, and leg press and a time trial during DP roller skiing. The results expressed strong correlations between roller skiing time trial performance and maximal strength in pull-down, both independent (rxy = −0.83, p < 0.01) and dependent (rxy–z = −0.50, p < 0.02) of sex. Higher maximal upper body strength was related to higher DP peak forces (PF) (rxy = 0.78, p < 0.02), lower DP frequency (rxy = −0.71, p < 0.01), and shorter DP contact time (CT) (rxy = −0.48, p < 0.02). The practical implications of the present study is to acknowledge maximal upper body strength as a performance determining factor in DP. This point at the importance of including maximal strength training in cross-country skiers training programs.
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Affiliation(s)
- Arnstein Sunde
- Department of Sport and Outdoor Life Studies, University of South-Eastern Norway, Bø, Norway
| | - Jan-Michael Johansen
- Department of Sport and Outdoor Life Studies, University of South-Eastern Norway, Bø, Norway
| | - Martin Gjøra
- Department of Sport and Outdoor Life Studies, University of South-Eastern Norway, Bø, Norway
| | - Gøran Paulsen
- Department of Technical and Motor Development, The Norwegian Olympic Sports Center, Oslo, Norway
| | - Morten Bråten
- Department of Technical and Motor Development, The Norwegian Olympic Sports Center, Oslo, Norway
| | - Jan Helgerud
- Department of Circulation and Medical Imaging, Faculty of Medicine Trondheim, Norwegian University of Science and Technology, Trondheim, Norway.,Myworkout, Medical Rehabilitation Centre, Trondheim, Norway
| | - Øyvind Støren
- Department of Sport and Outdoor Life Studies, University of South-Eastern Norway, Bø, Norway
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Støa EM, Meling S, Nyhus LK, Glenn Strømstad, Mangerud KM, Helgerud J, Bratland-Sanda S, Støren Ø. High-intensity aerobic interval training improves aerobic fitness and HbA1c among persons diagnosed with type 2 diabetes. Eur J Appl Physiol 2017; 117:455-467. [PMID: 28160083 DOI: 10.1007/s00421-017-3540-1] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Accepted: 01/09/2017] [Indexed: 12/16/2022]
Abstract
PURPOSE It remains to be established how high-intensity aerobic interval training (HAIT) affects risk factors associated with type 2 diabetes (TD2). This study investigated effects of HAIT on maximal oxygen uptake (VO2max), glycated Hemoglobin type A1C (HbA1c), insulin resistance (IR), fat oxidation (FatOx), body weight (BW), percent body fat (%BF), lactate threshold (LT), blood pressure (BP), and blood lipid profile (BLP) among persons with T2D. Results were compared to the effects after a moderate-intensity training (MIT) program. METHODS Thirty-eight individuals with T2D completed 12 weeks of supervised training. HAIT consisted of 4 × 4 min of walking or running uphill at 85-95% of maximal heart rate, and MIT consisted of continuous walking at 70-75% of maximal heart rate. RESULTS A 21% increase in VO2max (from 25.6 to 30.9 ml kg-1 min-1, p < 0.001), and a reduction in HbA1c by -0.58% points (from 7.78 to 7.20%, p < 0.001) was found in HAIT. BW and body mass index (BMI) was reduced by 1.9% (p < 0.01). There was a tendency towards an improved FatOx at 60% VO2max (14%, p = 0.065). These improvements were significant different from MIT. Both HAIT and MIT increased velocity at LT, and reduced %BF, waist circumference, hip circumference, and BP, with no significant differences between the two groups. Correlations were found between change in VO2max and change in HbA1c when the two intervention groups were combined (R = -0.52, p < 0.01). CONCLUSION HAIT is an effective exercise strategy to improve aerobic fitness and reduce risk factors associated with T2D.
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Affiliation(s)
- Eva Maria Støa
- Department of Sports, Physical Education and Outdoor Life Studies, University College of Southeast Norway, Bø, Porsgrunn, Norway.
| | - Sondre Meling
- Department of Endocrinology, Stavanger University Hospital, Former Hospital of Telemark, Stavanger, Norway
| | - Lill-Katrin Nyhus
- Department of Sports, Physical Education and Outdoor Life Studies, University College of Southeast Norway, Bø, Porsgrunn, Norway
| | - Glenn Strømstad
- Department of Sports, Physical Education and Outdoor Life Studies, University College of Southeast Norway, Bø, Porsgrunn, Norway
| | - Karl Magnus Mangerud
- Department of Sports, Physical Education and Outdoor Life Studies, University College of Southeast Norway, Bø, Porsgrunn, Norway
| | - Jan Helgerud
- Department of Sports, Physical Education and Outdoor Life Studies, University College of Southeast Norway, Bø, Porsgrunn, Norway.,Department of Circulation and Medical Imaging, Faculty of Medicine, Norwegian University of Science and Technology, Trondheim, Norway.,Hokksund Medical Rehabilitation Center, Hokksund, Norway
| | - Solfrid Bratland-Sanda
- Department of Sports, Physical Education and Outdoor Life Studies, University College of Southeast Norway, Bø, Porsgrunn, Norway
| | - Øyvind Støren
- Department of Sports, Physical Education and Outdoor Life Studies, University College of Southeast Norway, Bø, Porsgrunn, Norway
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