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Exercise-induced trunk fatigue decreases double poling performance in well-trained cross-country skiers

Authors:
Elias Bucher at Swiss Federal Institute of Sport Magglingen SFISM
Elias Bucher
Oyvind Sandbakk at UiT The Artic University of Norway
Oyvind Sandbakk
  • UiT The Artic University of Norway
Lars Donath at Deutsche Sporthochschule Köln
Lars Donath
Ralf Roth at University of Basel
Ralf Roth
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Purpose: To examine the effects of exercise-induced trunk fatigue on double poling performance, physiological responses and trunk strength in cross-country skiers. Methods: Sixteen well-trained male cross-country skiers completed two identical pre- and post-performance tests, separated by either a 25-min trunk fatiguing exercise sequence or rest period in a randomized, controlled cross-over design. Performance tests consisted of a maximal trunk flexion and extension test, followed by a 3-min double poling (DP) test on a ski ergometer. Results: Peak torque during isometric trunk flexion (- 66%, p < .001) and extension (- 7.4%, p = .03) decreased in the fatigue relative to the control condition. Mean external power output during DP decreased by 14% (p < .001) and could be attributed both to reduced work per cycle (- 9%, p = .019) and a reduced cycle rate (- 6%, p = .06). Coinciding physiological changes in peak oxygen uptake (- 6%, p < .001) and peak ventilation (- 7%, p < .001) could be observed. Skiers chose a more even-pacing strategy when fatigued, with the performance difference between fatigue and control condition being most prominent during the first 2 min of the post-test. Conclusions: In well-trained cross-country skiers, exercise-induced trunk fatigue led to a substantial decrease in DP performance, caused by both decreased work per cycle and cycle rate and accompanied by reduced aerobic power. Hence, improved fatigue resistance of the trunk may therefore be of importance for high-intensity DP in cross-country skiing.
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European Journal of Applied Physiology (2018) 118:2077–2087
https://doi.org/10.1007/s00421-018-3938-4
ORIGINAL ARTICLE
Exercise-induced trunk fatigue decreases double poling performance
inwell-trained cross-country skiers
EliasBucher1,2 · ØyvindSandbakk3· LarsDonath1,4· RalfRoth1· LukasZahner1· OliverFaude1
Received: 9 April 2018 / Accepted: 6 July 2018 / Published online: 13 July 2018
© Springer-Verlag GmbH Germany, part of Springer Nature 2018
Abstract
Purpose To examine the effects of exercise-induced trunk fatigue on double poling performance, physiological responses
and trunk strength in cross-country skiers.
Methods Sixteen well-trained male cross-country skiers completed two identical pre- and post-performance tests, separated
by either a 25-min trunk fatiguing exercise sequence or rest period in a randomized, controlled cross-over design. Performance
tests consisted of a maximal trunk flexion and extension test, followed by a 3-min double poling (DP) test on a ski ergometer.
Results Peak torque during isometric trunk flexion (− 66%, p < .001) and extension (− 7.4%, p = .03) decreased in the fatigue
relative to the control condition. Mean external power output during DP decreased by 14% (p < .001) and could be attributed
both to reduced work per cycle (− 9%, p = .019) and a reduced cycle rate (− 6%, p = .06). Coinciding physiological changes
in peak oxygen uptake (− 6%, p < .001) and peak ventilation (− 7%, p < .001) could be observed. Skiers chose a more even-
pacing strategy when fatigued, with the performance difference between fatigue and control condition being most prominent
during the first 2min of the post-test.
Conclusions In well-trained cross-country skiers, exercise-induced trunk fatigue led to a substantial decrease in DP perfor-
mance, caused by both decreased work per cycle and cycle rate and accompanied by reduced aerobic power. Hence, improved
fatigue resistance of the trunk may therefore be of importance for high-intensity DP in cross-country skiing.
Keywords Core· Ergometer· Ski· Power output· Technique
Abbreviations
1RM One repetition maximum
3MT 3-min test
ANOVA Analysis of variance
BLa Blood lactate concentration
CON Control condition
CV Coefficient of variation
DP Double poling
FAT Fatigue condition
HRpeak Peak heart rate
ICC Intra-class coefficient
RPE Rating of perceived exertion
RER Respiratory exchange ratio
SD Standard deviation
VEpeak Peak ventilation
VO2max Maximal oxygen uptake
VO2peak Peak oxygen uptake
W Watt
Introduction
Cross-country skiing is a demanding endurance sport
involving various skiing techniques where skiers load the
upper-body, trunk and lower-body to different extents on
Communicated by Bénédicte Schepens.
Electronic supplementary material The online version of this
article (https ://doi.org/10.1007/s0042 1-018-3938-4) contains
supplementary material, which is available to authorized users.
* Elias Bucher
elias.bucher@baspo.admin.ch
1 Department ofSport, Exercise andHealth, University
ofBasel, Basel, Switzerland
2 Swiss Federal Institute ofSport, Section forElite Sport,
Magglingen, Switzerland
3 Centre forElite Sports Research, Department
ofNeuromedicine andMovement Science, Norwegian
University ofScience andTechnology, Trondheim, Norway
4 Department ofIntervention Research inExercise Training,
German Sport University Cologne, Cologne, Germany
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
... Increasing load during endurance sports challenges both the cardiovascular and the central nervous system. While a well-adapted cardiovascular system is required to sufficiently supply the working muscles with metabolic energy during exercise, a highly developed interaction within the central nervous system is mandatory for motor coordination between upper-limb, trunk and lower-limb muscles (Bucher et al. 2018). In this regard, a precise sequential order of movements is crucial for the athlete to move efficiently during exercise, especially in technically demanding endurance sports (Holmberg et al. 2005). ...
... In this regard, a precise sequential order of movements is crucial for the athlete to move efficiently during exercise, especially in technically demanding endurance sports (Holmberg et al. 2005). However, several investigations observed that high exercise load can impair the sequential coordination of limb movement, which consequently leads to reduced power output and reduced performance (Bassan et al. 2015;Bucher et al. 2018 et al. 2009). It has been suggested that such effects can be explained by modulations in both central and peripheral neural circuits leading to impaired coupling of sensory perception and motor execution (McMorris et al. 2015). ...
... Behavioral observations propose that exercise and brain function interact in a dose-response relationship, assigning the most beneficial effect on brain function to moderate-to high-intensity exercise (Herold et al. 2019). In line with that, exhaustive exercise is associated with loss of distinct brain function, for instance, expressed by altered kinematics in cyclic motor tasks (Bassan et al. 2015;Bucher et al. 2018;Zory et al. 2009). Consequently, the analysis of modulations of regional brain activity does not reflect this intensity-dependent pattern. ...
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... Thus, breathing control through adequate levels of trunk muscles might be important for rowing performance, especially towards the end of the race. This can be linked to Bucher et al. (2018), who examined the change in double pooling performance after an exercise-induced trunk fatigue in well trained cross-country skiers. Their poorer performance was accompanied by lower ventilation and lower VO2peak, which might be due to negative influence on respiratory muscle function, technique and posture, which all affect conditions for breathing 41 . ...
... This can be linked to Bucher et al. (2018), who examined the change in double pooling performance after an exercise-induced trunk fatigue in well trained cross-country skiers. Their poorer performance was accompanied by lower ventilation and lower VO2peak, which might be due to negative influence on respiratory muscle function, technique and posture, which all affect conditions for breathing 41 . However, there is no data on this topic in rowing yet. ...
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... Thus, breathing control through adequate levels of trunk muscles might be important for rowing performance, especially towards the end of the race. This can be linked to Bucher et al. (2018), who examined the change in double pooling performance after an exercise-induced trunk fatigue in well trained cross-country skiers. Their poorer performance was accompanied by lower ventilation and lower VO2peak, which might be due to negative influence on respiratory muscle function, technique and posture, which all affect conditions for breathing 41 . ...
... This can be linked to Bucher et al. (2018), who examined the change in double pooling performance after an exercise-induced trunk fatigue in well trained cross-country skiers. Their poorer performance was accompanied by lower ventilation and lower VO2peak, which might be due to negative influence on respiratory muscle function, technique and posture, which all affect conditions for breathing 41 . However, there is no data on this topic in rowing yet. ...
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... In addition, it has been shown that trunk muscles fatigue is associated with running kinematics changes (Hart et al. 2009), and influences running economy adversely (Drum, Rappelt, and Donath 2019). Also, in other sport activities, fatigue of trunk muscles decreases external power output and can reduce work per cycle in cross-country skiers (Bucher et al. 2018). ...
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  • Feb 2016
  • EUR J APPL PHYSIOL
Purpose: To characterize gender differences in power output, energetic capacity and exercise efficiency during whole-body (WP), upper-body (UP), and arm poling (AP). Methods: Ten male and ten female elite cross-country skiers, matched for international performance level, completed three incremental submaximal tests and a 3-min self-paced performance test on a Concept2 SkiErg. Power output, cardiorespiratory and kinematic variables were monitored. Body composition was determined by dual-energy X-ray absorptiometry. Results: The men demonstrated 87, 97 and 103 % higher power output, and 51, 65 and 71 % higher VO2peak (L min(-1)) than the women during WP, UP and AP, respectively, while utilizing ~10 % more of their running VO2max in all modes (all P < 0.001). The men had 35, 38 and 59 % more lean mass in the whole body, upper body and arms (all P < 0.001). The men exhibited greater shoulder and elbow extension at the start of poling and greater trunk flexion at the end of poling (all P < 0.05). The relationship between VO2 and power output did not differ between the men and women. Conclusions: Gender differences in power production and peak aerobic capacity increased sequentially from WP to UP to AP, coinciding with a greater portion of the muscle mass in the arms of the men. Although the men and women employed each poling technique differently, the estimated efficiency of double poling was independent of gender.
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Non-local muscle fatigue: effects and possible mechanisms
Article
Full-text available
  • Sep 2015
  • EUR J APPL PHYSIOL
Non-local muscle fatigue (NLMF) is characterized by muscle performance impairments in a contralateral or remote non-exercised muscle(s) following a fatiguing protocol of a different muscle group(s). This topic is of interest as it affords insights into physiological determinants of muscle fatigue and may provide practical applications concerning the order of exercises in training and rehabilitation programs. A literature review was conducted using Web of Science, PubMed, and Google Scholar databases to evaluate the NLMF effects and possible underlying mechanisms. Overall, 35 studies with 58 outcome measures that met the inclusion criteria were identified. The literature is conflicting with approximately half of the studies reporting NLMF effects (32 of 58 measurements). However, on closer examination 76 % of outcome measures of the lower limbs reported NLMF effects (23 of 30 measurements) compared to only 32 % in the upper body (9 of 28 measurements). Thus, it appears that NLMF effects may be muscle group dependent. Also, tests that involve prolonged or repetitive contractions provide clearer evidence of NLMF. Other variables potentially influencing the size of the NLMF effect include the fatigued muscle groups, the protocols used to elicit the fatigue, gender and training background of participants. While the NLMF literature is conflicting, certain variables appear to affect NLMF responses which can account for some of the discrepancies. Furthermore, the NLMF effects may be attributed to four different but interconnected pathways: neurological, biochemical, biomechanical and psychological.
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Absolute and relative reliability of isokinetic and isometric trunk strength testing using the IsoMed-2000 dynamometer
Article
  • Nov 2016
Objectives: The present study aimed to assess the between day reliability of isokinetic and isometric peak torque (PT) during trunk measurement on an isokinetic device (IsoMed 2000). Design: Test-retest-protocol on five separate days. Participants: Fifteen healthy sport students (8 female and 7 male) aged 21 to 26. Main outcome measures: PT was assessed in isometric back extension and flexion as well as right and left rotation. Isokinetic strength was captured at a speed of 60°/s and 150°/s for all tasks. Results: For none of the assessed parameters a meaningful variation in PT during test days was observed. Relative reliability (ICC = 0.85-0.96) was excellent for all tasks. Estimates of absolute reliability as Coefficient of Variation (CoV) and Standard Error of Measurement (SEM in Nm/kg lean body mass) remained stable for isometric (6.9% < CoV < 9.4%; 0.15 < SEM < 0.23) and isokinetic mode (60°/s: 3.7% < CoV < 8.6%; 0.08 < SEM < 0.24; 150°/s: 6.9% < CoV < 12.4%; 0.10 < SEM < 0.31). In contrast, reliability between familiarization day and day 1 was lower (6.6% < CoV < 26.2%; 0.10 < SEM < 0.65). Conclusions: Trunk strength measurement in flexion and extension or trunk rotation in either isometric or isokinetic condition is highly reliable. Therefore, it seems possible to elucidate changes which are smaller than 10% due to intervention programs when a preceding familiarization condition was applied.
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Double-Poling Biomechanics of Elite Cross-country Skiers: Flat versus Uphill Terrain
Article
  • Mar 2016
  • MED SCI SPORT EXER
Introduction: In light of the recent revolutionary change in the use of the double-poling (DP) technique in cross-country skiing, our purpose was to compare the associated kinetics and kinematics on flat (DPflat) and uphill terrain (DPup), as well as to identify factors that determine performance. Methods: Thirteen elite male cross-country skiers completed two incremental speed tests (Vpeak) involving roller skiing with the DP technique at moderate (13 and 24 km·h) and high speed (15 and 28.5 km·h) on a treadmill that was flat (1°) or tilted uphill (7°). Pole forces and three-dimensional whole-body kinematics were monitored simultaneously. Results: In comparison to DPflat, during DPup, swing times were much shorter (-48%) and peak pole forces greater (+13%) and generated later during the poling phase (+68%), with higher impulses for all force components (+87%-123%). Furthermore, pole forces were 18% more effectively oriented for propulsion. During DPup, the skiers demonstrated more flexed elbows, as well as shoulder angles that were less flexed in the forward direction and less abducted throughout the poling phase, together with more highly flexed knee and ankle joints, a more upright thorax, less flexed hips, and a shortened backward swing after pole off. With DPup, the skiers raised their center of mass 25% more, attaining maximal heel raise and maximal vertical position at a timepoint closer to pole plant compared with flat. On the uphill incline, the magnitude of Vpeak was positively related to body mass, relative pole length (% body height), and magnitude of heel raise. Conclusions: The present findings provide novel insights into the coordination, kinetics and kinematics of elite skiers while DP on flat and uphill terrain.
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An Analysis of the Pacing Strategies Adopted by Elite Cross-Country Skiers
Article
  • Mar 2016
  • J STRENGTH COND RES
Understanding the pacing strategies employed by the most successful skiers may provide insight into the most desirable pacing approach in cross-country skiing. This study examined the pacing strategies adopted by male and female cross-country skiers of different performance standards during 10/15 km races in World Cup, World Championship and Olympic events. Analyses were carried out on races involving 5 km laps in the men's 15 km (number of races = 22) and the women's 10 km (n = 14) individual start races (classic and free style) from season 2002/2003 to season 2013/2014. Final rank and lap times for the 40 top finishers in each race were analyzed. Both genders demonstrated a positive pacing pattern shown by a decline in velocity from the first to the last lap (men: 6.76 ± 0.43 m·s vs. 6.47 ± 0.46 m·s, P < 0.001; women: 6.0 ± 0.47 m·s vs. 5.87 ± 0.53 m·s, P < 0.001). For the men, slower skiers (final ranking 21-30 and 31-40) were characterized by a quick start relative to their average velocity, with a greater decrease during the race compared with the fastest skiers (1-10) (P = 0.007 and P < 0.001, respectively). For the women, no group differences in pacing strategy were found. In conclusion, the present study shows that the pacing strategy indicates the standard of elite male cross-country skiers. Examining the pacing strategies of the best male performers suggests that lower-performing male skiers should consider a more even pacing strategy in order to improve their performance.
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The contribution of upper-body strength, body composition and maximal oxygen uptake to predict double poling power and overall performance in female cross-country skiers
Article
  • Jan 2016
Maximal oxygen uptake (VO2max) is regarded as the most performance-differentiating physiological measure in cross-country (XC) skiing. In addition, upper-body strength and lean mass have been associated with double poling (DP) power in XC skiers. In this study, we tested upper-body maximal strength, lean mass and VO2max’s contributions to predict DP power production of different duration and the overall XC skiing performance level of elite female XC skiers. Thirteen skiers (VO2max: 64.9 ± 4.2 mL∙kg-1∙min-1) performed one 30-s and one 3-min DP performance test using a ski ergometer. The International Ski Federation’s (FIS) ranking points determined their overall XC skiing performance. The skiers performed three one-repetition maximal strength tests in poling-specific exercises that isolated the elbow extension, shoulder extension, and trunk flexion movements. Body composition was determined by a DXA scan, and VO2max was tested in an incremental running test. Multiple regressions were employed to predict power production in the 30-s and 3-min tests as well as FIS-points. The two best predictions of 30-s DP power were lean upper-body mass and maximal upper-body strength (with the three strength tests normalized and pooled together as one variable) (R2=0.84 and 0.81, p<0.001). Along with VO2max, the same two variables were the best predictions of both 3-min DP power (R2=0.60 and 0.44, p<0.05) and overall XC skiing performance (R2=0.43 and 0.40, p<0.05). While the importance of upper-body strength and lean mass to predict DP power production as well the overall XC skiing performance declines with the performance duration in female cross-country skiers, the importance of VO2max shows an opposite relationship.
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