Using Inertial Measurement Units to Examine Selected Joint Kinematics in a Road Cycling Sprint: A Series of Single Cases.

Sprinting plays a significant role in determining the results of road cycling races worldwide. However, currently, there is a lack of systematic research into the kinematics of sprint cycling, especially in an outdoor, environmentally valid setting. This study aimed to describe selected joint kinematics during a cycling sprint outdoors. Three participants were recorded sprinting over 60 meters in both standing and seated sprinting positions on an outdoor course with a baseline condition of seated cycling at 20 km/h. The participants were recorded using array-based inertial measurement units to collect joint excursions of the upper and lower limbs including the trunk. A high-rate GPS unit was used to record velocity during each recorded condition. Kinematic data were analyzed in a similar fashion to running gait, where multiple pedal strokes were identified, delineated, and averaged to form a representative (average ± SD) waveform. Participants maintained stable kinematics in most joints studied during the baseline condition, but variations in ranges of movement were recorded during seated and standing sprinting. Discernable patterns started to emerge for several kinematic profiles during standing sprinting. Alternate sprinting strategies emerged between participants and bilateral asymmetries were also recorded in the individuals tested. This approach to studying road cycling holds substantial potential for researchers wishing to explore this sport.

Field- and Laboratory-derived Power-Cadence Profiles in World-Class and Elite Track Sprint Cyclists.

Previous investigations comparing Torque-Cadence (T-C) and Power-Cadence (P-C) profiles derived from seated and standing positions and field and laboratory conditions are not congruent with current methodological recommendations. Consequently, the aim of this investigation was to compare seated and standing T-C and P-C profiles generated from field and laboratory testing. Thirteen world-class and elite track sprint cyclists (n = 7 males, maximal power output (Pmax) = 2112 ± 395 W; n = 6 females, Pmax = 1223 ± 102 W) completed two testing sessions in which field- and laboratory-derived T-C and P-C profiles were identified. Standing P-C profiles had significantly (p < 0.05) greater Pmax than seated profiles, however there were no significant differences in optimal cadence (Fopt) between seated and standing positions. Pmax and Fopt were significantly lower in field-derived profiles in both positions compared to laboratory-derived profiles. However, there was no significant difference in the goodness-of-fit (R2) of the P-C profiles between laboratory (0.985 ± 0.02) and field-testing (0.982 ± 0.02) in each position. Valid T-C and P-C profiles can be constructed from field and laboratory protocols; however, the mechanical variables derived from the seated and standing and field and laboratory profiles cannot be used interchangeably. Both field and laboratory-derived profiles provide meaningful information and provide complementary insights into cyclists' capacity to produce power output.

Track cycling sprint sex differences using power data.

Objectives: Currently, there are no data on sex differences in the power profiles in sprint track cycling. This cross-section study analyses retrospective data of female and male track sprint cyclists for sex differences. We hypothesized that women would exhibit lower peak power to weight than men, as well as demonstrate a different distribution of power durations related to sprint cycling performance. Design: We used training, testing, and racing data from a publicly available online depository (www.strava.com), for 29 track sprint cyclists (eight women providing 18 datasets, and 21 men providing 54 datasets) to create sex-specific profiles. R2 was used to describe model quality, and regression indices are used to compare watts per kilogram (W/kg) for each duration for both sexes against a 1:1 relationship expected for 15-s:15-s W/kg. Results: We confirmed our sample were sprint cyclists, displaying higher peak and competition power than track endurance cyclists. All power profiles showed a high model quality (R2 ≥ 0.77). Regression indices for both sexes were similar for all durations, suggesting similar peak power and similar relationship between peak power and endurance level for both men and women (rejecting our hypothesis). The value of R2 for the female sprinters showed greater variation suggesting greater differences within female sprint cyclists. Conclusion: The main finding shows female sprint cyclists in this study have very similar relationships between peak power and endurance power as men. Higher variation in W/kg for women in this study than men, within these strong relationships, indicates women in this study, had greater inter-athlete variability, and may thus require more personalised training. Future work needs to be performed with larger samples, and at different levels to optimize these recommendations.

Biomechanical measures of short-term maximal cycling on an ergometer: a test-retest study.

An understanding of test-retest reliability is important for biomechanists, such as when assessing the longitudinal effect of training or equipment interventions. Our aim was to quantify the test-retest reliability of biomechanical variables measured during short-term maximal cycling. Fourteen track sprint cyclists performed 3 × 4 s seated sprints at 135 rpm on an isokinetic ergometer, repeating the session 7.6 ± 2.5 days later. Joint moments were calculated via inverse dynamics, using pedal forces and limb kinematics. EMG activity was measured for 9 lower limb muscles. Reliability was explored by quantifying systematic and random differences within- and between-session. Within-session reliability was better than between-sessions reliability. The test-retest reliability level was typically moderate to excellent for the biomechanical variables that describe maximal cycling. However, some variables, such as peak knee flexion moment and maximum hip joint power, demonstrated lower reliability, indicating that care needs to be taken when using these variables to evaluate biomechanical changes. Although measurement error (instrumentation error, anatomical marker misplacement, soft tissue artefacts) can explain some of our reliability observations, we speculate that biological variability may also be a contributor to the lower repeatability observed in several variables including ineffective crank force, ankle kinematics and hamstring muscles' activation patterns.

Assessing the rate of torque development in sprint cycling: a methodological study.

The present study examined (i) the magnitude of the rate of torque development (RTD) and (ii) the between-day reliability of RTD at the start of a cycling sprint when sprint resistance, sprint duration, and the pedal downstroke were altered. Nineteen well-trained cyclists completed one familiarisation and three testing sessions. Each session involved one set of 1-s sprints and one set of 5-s sprints. Each set contained one moderate (0.3 N m kg-1), one heavy (0.6 N m kg-1), and one very heavy (1.0 N m kg-1) resistance sprint. RTD measures (average and peak RTD, RTD 0-100 ms, and RTD 0-200 ms) were calculated for downstroke 1 in the 1-s sprint. For the 5-s sprints, RTD measures were calculated for each of the first three downstrokes, as an average of downstrokes 1 and 2, and as an average of downstrokes 2 and 3. Whilst RTDs were greatest in downstroke 3 at all resistances, the greatest number of reliable RTD measures were obtained using the average of downstrokes 2 and 3 with heavy or very heavy resistances, where average and peak RTD, and RTD 0-200 ms were deemed reliable (ICC ≥ 0.8, CV ≤ 10%). Since only 1-2 downstrokes can be completed within 1 s, the greatest RTD reliability cannot be achieved using a 1-s sprint; therefore, the average of downstrokes 2 and 3 during a >2-s cycling sprint (e.g. 5-s test) with heavy or very heavy resistance is recommended for the assessment of RTD in sprint cyclists.HighlightsWhilst RTD measures were greatest in pedal downstroke 3 at all resistances, the greatest number of reliable RTD measures were obtained using the average of pedal downstrokes 2 and 3 with heavy or very heavy resistances, with average and peak RTD, and RTD 0-200 ms having acceptable reliability.RTD 0-100 ms and all RTD measurements for downstroke 1 were not reliable and should not be used. As only 1-2 downstrokes can be performed in 1 s, the greatest RTD reliability cannot be achieved using a 1-s sprint. Instead, RTD may be evaluated using a 5-s sprint.

The influence of cadence on fatigue during maximal sprint cycling in world-class and elite sprint cyclists.

Optimising cadence through appropriate gear selection is a key consideration for track sprint cycling performance, yet the influence of cadence on fatigue (i.e., decrement in power output) within a maximal sprint is not well understood. The aim of this study was to identify the influence of cadence on fatigue during maximal sprint cycling. Eleven world-class and elite track sprint cyclists (n = 6 men, maximal power output (Pmax) = 1894 ± 351 W, optimal cadence (Fopt) = 134 ± 8 rev∙min-1: n = 5 women, Pmax = 1114 ± 80 W, Fopt = 124 ± 8 rev∙min-1) completed two testing sessions where power-cadence profiles were constructed to determine the Fopt associated with Pmax. Cyclists also performed three maximal 15-s sprints (Fopt, ±15%Fopt) to identify fatigue per pedal stroke across these cadence ranges. There was no significant difference (p = 0.2) in the absolute fatigue per pedal stroke when cadence was fixed 15% above (16.7 ± 6.1 W∙stroke-1) and below (15.3 ± 5.1 W∙stroke-1) Fopt. Similarly, there was no significant difference in the relative fatigue per pedal stroke (% peak power∙stroke-1) across Fopt and ± 15%Fopt trials (p = 0.12). The relative decrement in power output is equivalent across the ± 15%Fopt cadence range. As such, a higher-geared, lower-cadence approach to maximal sprint cycling could be a viable method to minimise maximal pedal strokes and reduce the decrement in power output.

Quantifying the hip-ankle synergy in short-term maximal cycling.

Simulation studies have demonstrated that the hip and ankle joints form a task-specific synergy during the downstroke in maximal cycling to enable the power produced by the hip extensor muscles to be transferred to the crank. The existence of the hip-ankle synergy has not been investigated experimentally. Therefore, we sought to apply a modified vector coding technique to quantify the strength of the hip-ankle moment synergy in the downstroke during short-term maximal cycling at a pedalling rate of 135 rpm. Twelve track sprint cyclists performed 3 × 4 s seated sprints at 135 rpm, interspersed with 2 × 4 s seated sprints at 60 rpm on an isokinetic ergometer. Data from the 60 rpm sprints were not analysed in this study. Joint moments were calculated via inverse dynamics, using pedal forces and limb kinematics. The hip-ankle moment synergy was quantified using a modified vector coding method. Results showed, for 28.8% of the downstroke the hip and ankle moments were in-phase, demonstrating the hip and ankle joints tend to work in synergy in the downstroke, providing some support findings from simulation studies of cycling. At a pedalling rate of 135 rpm the hip-phase was most frequent (42.5%) significantly differing from the in- (P = 0.044), anti- (P < 0.001), and ankle-phases (P = 0.004), demonstrating hip-dominant action. We believe this method shows promise to answer research questions on the relative strength of the hip-ankle synergy between different cycling conditions (e.g., power output and pedalling rates).

Strength and Power Testing of Athletes: Associations of Common Assessments Over Time.

PURPOSE: This study examined the associations among common assessments for measuring strength and power in the lower body of high-performing athletes, including both cross-sectional and longitudinal data. METHODS: A total of 100 participants, including both male (n = 83) and female (n = 17) athletes (21 [4] y, 182 [9] cm, 78 [12] kg), were recruited for the study using a multicenter approach. The participants underwent physical testing 4 times. The first 2 sessions (1 and 2) were separated by ∼1 week, followed by a period of 2 to 6 months, whereas the last 2 sessions (3 and 4) were also separated by ∼1 week. The test protocol consisted of squat jumps, countermovement jumps, jump and reach, 30-m sprint, 1-repetition-maximum squat, sprint cycling, and a leg-press test. RESULTS: There were generally acceptable correlations among all performance measures. Variables from the countermovement jumps and leg-press power correlated strongly with all performance assessments (r = .52-.79), while variables from sprint running and squat-jump power displayed more incoherent correlations (r = .21-.82). For changes over time, the correlations were mostly strong, albeit systematically weaker than for cross-sectional measures. CONCLUSIONS: The associations observed among the performance assessments seem to be consistent for both cross-sectional data and longitudinal change scores. The weaker correlations for change scores are most likely mainly caused by lower between-subjects variations in the change scores than for the cross-sectional data. The present study provides novel information, helping researchers and practitioners to better interpret the relationships across common performance assessment methods.

Effects of strength training on the biomechanics and coordination of short-term maximal cycling.

The aim was to investigate the effects of a gym-based strength training intervention on biomechanics and intermuscular coordination patterns during short-term maximal cycling. Twelve track sprint cyclists performed 3 × 4 s seated sprints at 135 rpm, interspersed with 2 × 4 s seated sprints at 60 rpm on an isokinetic ergometer, repeating the session 11.6 ± 1.4 weeks later following a training programme that included two gym-based strength training sessions per week. Joint moments were calculated via inverse dynamics, using pedal forces and limb kinematics. EMG activity was measured for 9 lower limb muscles. Track cyclists 'leg strength" increased (7.6 ± 11.9 kg, P = 0.050 and ES = 0.26) following the strength training intervention. This was accompanied by a significant increase in crank power over a complete revolution for sprints at 135 rpm (26.5 ± 36.2 W, P = 0.028 and ES = 0.29). The increase in leg strength and average crank power was associated with a change in biceps femoris muscle activity, indicating that the riders successfully adapted their intermuscular coordination patterns to accommodate the changes in personal constraints to increase crank power.

Strength and Power Testing of Athletes: A Multicenter Study of Test-Retest Reliability.

PURPOSE: This study examined the test-retest reliability of common assessments for measuring strength and power of the lower body in high-performing athletes. METHODS: A total of 100 participants, including both male (n = 83) and female (n = 17) athletes (21 [4] y, 182 [9] cm, and 78 [12] kg), were recruited for this study, using a multicenter approach. The participants underwent physical testing 4 times. The first 2 sessions (1 and 2) were separated by ∼1 week, followed by a period of 2 to 6 months, whereas the last 2 sessions (3 and 4) were again separated by ∼1 week. The test protocol consisted of squat jumps, countermovement jumps, jump and reach, 30-m sprint, 1-repetition-maximum squat, sprint cycling, and a leg-press test. RESULTS: The typical error (%) ranged from 1.3% to 8.5% for all assessments. The change in means ranged from -1.5% to 2.5% for all assessments, whereas the interclass correlation coefficient ranged from .85 to .97. The smallest worthwhile change (0.2 of baseline SD) ranged from 1.2% to 5.0%. The ratio between the typical error (%) and the smallest worthwhile change (%) ranged from 0.5 to 1.2. When observing the reliability across testing centers, considerable differences in reliability were observed (typical error [%] ratio: 0.44-1.44). CONCLUSIONS: Most of the included assessments can be used with confidence by researchers and coaches to measure strength and power in athletes. Our results highlight the importance of controlling testing reliability at each testing center and not relying on data from others, despite having applied the same protocol.

Analysis of elite road-cycling sprints in relation to maximal power-velocity-endurance profile: a longitudinal one-case study.

The aims of the present study were to characterize the mechanical output of final road sprints of an elite sprinter during international competitions in relation to his power-velocity-endurance characteristics and to investigate the relationship between this sprint performance and the power produced during preceding phases of the race. The sprinter performed a set of short and long sprints (5 to 15-s) on a cycle ergometer to determine his maximal power-velocity-endurance profile. Based on eleven races, the distribution of power throughout each race, peak and mean power (Ppeak and Pmean ) and associated pedaling rates (vPpeak and vPmean ) during the final sprint were analyzed. The power-velocity-endurance profile of the sprinter indicated that his theoeretical mean maximal power and corresponding optimal pedaling rate ranged from 20.0 W.kg-1 (124 rpm) for a 1-s sprint to 15.0 W.kg-1 (109 rpm) for 20 s. Race data showed that final road sprints were mainly performed on the ascending limb of the power-velocity relationship (vPpeak , 104 ± 8 and vPmean , 101 ± 8 rpm). Additionally, Ppeak and Pmean were lower than the theoretical maximal power determined from the power-velocity-endurance profile (9.9 ± 7.0% and 10.6 ± 9.8%, respectively), which highlighted a significant state of fatigue induced by the race. Finally, sprint power exhibited a high variability between races and was strongly related to the level of power produced during the last minute before the sprint. These findings show the importance of considering both the power-velocity-endurance qualities and the power demand of the last lead-up phase before the sprint in order to optimize final sprint performance.

Maximal muscular power: lessons from sprint cycling.

Maximal muscular power production is of fundamental importance to human functional capacity and feats of performance. Here, we present a synthesis of literature pertaining to physiological systems that limit maximal muscular power during cyclic actions characteristic of locomotor behaviours, and how they adapt to training. Maximal, cyclic muscular power is known to be the main determinant of sprint cycling performance, and therefore we present this synthesis in the context of sprint cycling. Cyclical power is interactively constrained by force-velocity properties (i.e. maximum force and maximum shortening velocity), activation-relaxation kinetics and muscle coordination across the continuum of cycle frequencies, with the relative influence of each factor being frequency dependent. Muscle cross-sectional area and fibre composition appear to be the most prominent properties influencing maximal muscular power and the power-frequency relationship. Due to the role of muscle fibre composition in determining maximum shortening velocity and activation-relaxation kinetics, it remains unclear how improvable these properties are with training. Increases in maximal muscular power may therefore arise primarily from improvements in maximum force production and neuromuscular coordination via appropriate training. Because maximal efforts may need to be sustained for ~15-60 s within sprint cycling competition, the ability to attenuate fatigue-related power loss is also critical to performance. Within this context, the fatigued state is characterised by impairments in force-velocity properties and activation-relaxation kinetics. A suppression and leftward shift of the power-frequency relationship is subsequently observed. It is not clear if rates of power loss can be improved with training, even in the presence adaptations associated with fatigue-resistance. Increasing maximum power may be most efficacious for improving sustained power during brief maximal efforts, although the inclusion of sprint interval training likely remains beneficial. Therefore, evidence from sprint cycling indicates that brief maximal muscular power production under cyclical conditions can be readily improved via appropriate training, with direct implications for sprint cycling as well as other athletic and health-related pursuits.

Impact of hydrogen-rich gas mixture inhalation through nasal cannula during post-exercise recovery period on subsequent oxidative stress, muscle damage, and exercise performances in men.

Molecular hydrogen has been suggested to have a cytoprotective effect on the whole body and to enhance exercise performances. However, the effect of hydrogen-rich gas mixture (HG) inhalation on physiological responses has been poorly investigated. We examined the impact of acute HG inhalation on subsequent oxidative stress, muscle damage, and exercise performances during the recovery period after a strenuous exercise. This is a two-trial, double-blind, crossover, repeated measures study. Eight physically active male volunteers inhaled HG (estimated fraction of inspired oxygen and hydrogen were 21.57 and 4.08% at most, respectively) or normal gas (placebo, ambient air 400 m above sea level) during a 60-minute recovery phase after oxidative stress-inducing exercise) completion comprising 30-minute treadmill running at an intensity corresponding to 75% of maximal oxygen uptake and squat jumps (5 sets × 10 repetitions). Before oxidative stress-inducing exercise and 10 minutes after the post-exercise gas inhalation, blood and urine samples were obtained and exercise performances (jumping ability; pedaling power output; muscle strength) were evaluated. Post-exercise HG inhalation attenuated the increase in urinary 8-hydroxydeoxyguanosine excretion rate (P < 0.05), a DNA oxidation marker, and the reduction in the countermovement jump height (P < 0.05), compared with Placebo inhalation. Other exercise performances and blood oxidative stress and muscle damage markers did not differ between HG and Placebo inhalation. Moreover, the increase in urinary 8-hydroxydeoxyguanosine excretion rate was significantly associated with countermovement jump performance reduction (r = -0.78, P < 0.01). These findings suggested that HG inhalation during post-exercise recovery period might improve exercise performance via reducing systemic oxidative damage. The study was approved by the Human Research Ethics Committee of the University of Yamanashi (approval No. H29-006) on June 28, 2017.

Caffeinated Chewing Gum Improves Bicycle Motocross Time-Trial Performance.

This study aimed to identify the acute effects of caffeinated chewing gum (CAF) on bicycle motocross (BMX) time-trial (TT) performance. In a randomized, placebo-controlled, double-blind cross-over design, 14 male BMX riders (age = 20.0 ± 3.3 years; height = 1.78 ± 0.04 m; body mass = 72 ± 4 kg), consumed either (300 mg; 4.2 ± 0.2 mg/kg) caffeinated (300 mg caffeine, 6 g sugars) or a placebo (0 mg caffeine, 0 g sugars) gum, and undertook three BMX TTs. Repeated-measure analysis revealed that CAF has a large ergogenic effect on TT time, F(1, 14) = 33.570, p = .001, ηp2=.71; -1.5% ± 0.4 compared with the placebo. Peak power and maximal power to weight ratio also increased significantly compared with the placebo condition, F(1, 14) = 54.666, p = .001, ηp2=.79; +3.5% ± 0.6, and F(1, 14) = 57.399, p = .001, ηp2=.80; +3% ± 0.3, respectively. Rating of perceived exertion was significantly lower F(1, 14) = 25.020, p = .001, ηp2=.64 in CAF (6.6 ± 1.3) compared with the placebo (7.2 ± 1.7). Administering a moderate dose (300 mg) of CAF could improve TT time by enhancing power and reducing the perception of exertion. BMX coaches and riders may consider consuming CAF before a BMX race to improve performance and reduce rating of perceived exertion.

Hydrogen-rich water suppresses the reduction in blood total antioxidant capacity induced by 3 consecutive days of severe exercise in physically active males.

Repeated sprint exercise can interfere with intramuscular redox balance and cause systemic oxidative stress and muscle damage. There is growing evidence that molecular hydrogen counteracts oxidative and/or inflammatory responses. Therefore, we investigated the effects of molecular hydrogen-rich water (HW) on muscle performance and oxidative stress markers induced by strenuous exercise. A single-blind, crossover, randomized controlled trial has been designed. Eight male volunteers completed two 3-day consecutive exercise tests under two conditions: HW and placebo water (PW). The exercise test included a countermovement jump, maximal voluntary isometric contraction of knee extensors, and sprint cycling. The sprint cycling exercise was comprised three repetitions of 10-second maximal pedaling against a resistance of 7.5% body mass and 110-second active rest (no-load pedaling). Before and after the exercise test, participants drank the 500 mL of HW (5.14 ± 0.03 ppm in H2 concentration) or PW (0.00 ± 0.00 ppm). At 7 hours before the first exercise test (Day 1), as baseline, and 16 hours after the exercise test on each day, blood samples were obtained. Exercise performances in both conditions were not significantly different over 3 consecutive days. In PW trial, relative changes in biological antioxidant potential/diacron-reactive oxygen metabolites, as an index of systemic antioxidant potential, from baseline gradually decreased as the day passed. However, HW suppressed the reduction in biological antioxidant potential/diacron-reactive oxygen metabolites observed in PW. Drinking HW contributed to the maintenance of the redox status during consecutive days of strenuous exercise and might help prevent accumulative muscular fatigue. The study was approved by the Human Research Ethics Committee of the University of Yamanashi, Japan (approval No. H26-008) on December 17, 2014.

Relationship between Cyclic and Non-Cyclic Force-Velocity Characteristics in BMX Cyclists.

Especially for bicycle motocross (BMX) cyclists, transfer of muscular force-velocity (Fv) characteristics between common strength training exercises and cycling is important. This study investigated the relationship between Fv characteristics in a common training exercise (squat jumps) and a sport-specific task (cycling) in high-level BMX racers by exploring the degree to which Fv and torque-cadence (Tc) characteristics correspond. Twelve BMX racers performed an Fv (multiple loaded squat jump) and two Tc tests (ramp starts and flat-ground sprints). Results revealed very large correlations between F 0 and T o r 0   s t a r t (r = 0.77) and between P m a x   j u m p and P m a x   s t a r t (r = 0.85). On the other hand, the relationships between v 0 and C a d 0   s t a r t (r = -0.25) and between S F v and S T c   s t a r t (r = -0.14) were small and negative. Similar results were observed for sprints. Based on dichotomous classifications (greater or less than group median), several discrepancies occurred, particularly for the profile slopes and high-speed variables. Thus, we recommend performing both jump-based and cycling-specific F v testing. Of additional note, T c characteristics on flat ground were similar to, but slightly different from those on the start ramp. Therefore, where possible, Tc tests should be carried out on a ramp.

Creatine-electrolyte supplementation improves repeated sprint cycling performance: A double blind randomized control study.

BACKGROUND: Creatine supplementation is recommended as an ergogenic aid to improve repeated sprint cycling performance. Furthermore, creatine uptake is increased in the presence of electrolytes. Prior research examining the effect of a creatine-electrolyte (CE) supplement on repeated sprint cycling performance, however, did not show post-supplementation improvement. The purpose of this double blind randomized control study was to investigate the effect of a six-week CE supplementation intervention on overall and repeated peak and mean power output during repeated cycling sprints with recovery periods of 2 min between sprints. METHODS: Peak and mean power generated by 23 male recreational cyclists (CE group: n = 12; 24.0 ± 4.2 years; placebo (P) group: n = 11; 23.3 ± 3.1 years) were measured on a Velotron ergometer as they completed five 15-s cycling sprints, with 2 min of recovery between sprints, pre- and post-supplementation. Mixed-model ANOVAs were used for statistical analyses. RESULTS: A supplement-time interaction showed a 4% increase in overall peak power (pre: 734 ± 75 W; post: 765 ± 71 W; p = 0.040; ηp2 = 0.187) and a 5% increase in overall mean power (pre: 586 ± 72 W; post: 615 ± 74 W; p = 0.019; ηp2 = 0.234) from pre- to post-supplementation for the CE group. For the P group, no differences were observed in overall peak (pre: 768 ± 95 W; post: 772 ± 108 W; p = 0.735) and overall mean power (pre: 638 ± 77 W; post: 643 ± 92 W; p = 0.435) from pre- to post-testing. For repeated sprint analysis, peak (pre: 737 ± 88 W; post: 767 ± 92 W; p = 0.002; ηp2 = 0.380) and mean (pre: 650 ± 92 W; post: 694 ± 87 W; p < 0.001; ηp2 = 0.578) power output were significantly increased only in the first sprint effort in CE group from pre- to post-supplementation testing. For the P group, no differences were observed for repeated sprint performance. CONCLUSION: A CE supplement improves overall and repeated short duration sprint cycling performance when sprints are interspersed with adequate recovery periods.

Allometric scaling of power-force-velocity ergometry profiles in men.

AIM: To examine the appropriate magnitude of allometric scaling of the force-velocity relationship according to body dimensions and to establish normative data for the power-force-velocity relationship for active men. SUBJECTS AND METHODS: Ninety-seven participants completed a force-velocity test on a Monark cycle ergometer. Allometric exponents and percentile ranks were established for maximal power (Pmax), maximal force (F0) and maximal velocity (V0). RESULTS: The mean (± SD) of Pmax, F0 and V0 were 1114.90 ± 160.60 W, 191.97 ± 26.51 N, and 227.87 ± 8.82 rpm, respectively. V0 was not related to any body size descriptors. Allometric exponents for Pmax, and F0 scaled for body mass were b = 0.77 (0.64-0.90) and 0.74 (0.61-0.86), respectively. Correlations between allometrically scaled Pmax and F0 with body mass were r = 0.002 (p = 0.984) and r = 0.008 (p = 0.940), respectively, suggesting that the allometric exponents derived were effective in partialling out the effect of body mass on Pmax and F0 results. CONCLUSIONS: The allometric exponents and normative values of the current study provide a useful tool for comparing the scores of force-velocity tests between individuals without the confounding effect of body size.

Relation between Peak Power Output in Sprint Cycling and Maximum Voluntary Isometric Torque Production.

From a cycling paradigm, little has been done to understand the relationships between maximal isometric strength of different single joint lower body muscle groups and their relation with, and ability to predict PPO and how they compare to an isometric cycling specific task. The aim of this study was to establish relationships between maximal voluntary torque production from isometric single-joint and cycling specific tasks and assess their ability to predict PPO. Twenty male trained cyclists participated in this study. Peak torque was measured by performing maximum voluntary contractions (MVC) of knee extensors, knee flexors, dorsi flexors and hip extensors whilst instrumented cranks measured isometric peak torque from MVC when participants were in their cycling specific position (ISOCYC). A stepwise regression showed that peak torque of the knee extensors was the only significant predictor of PPO when using SJD and accounted for 47% of the variance. However, when compared to ISOCYC, the only significant predictor of PPO was ISOCYC, which accounted for 77% of the variance. This suggests that peak torque of the knee extensors was the best single-joint predictor of PPO in sprint cycling. Furthermore, a stronger prediction can be made from a task specific isometric task.

Comparison of ergometer- and track-based testing in junior track-sprint cyclists. Implications for talent identification and development.

Talent identification (TID) and talent development (TDE) programmes in track sprint cycling use ergometer- and track-based tests to select junior athletes and assess their development. The purpose of this study was to assess which tests are best at monitoring TID and TDE. Ten male participants (16.2 ± 1.1 year; 178.5 ± 6.0 cm and 73.6 ± 7.6 kg) were selected into the national TID squad based on initial testing. These tests consisted of two 6-s maximal sprints on a custom-built ergometer and 4 maximal track-based tests (2 rolling and 2 standing starts) using 2 gear ratios. Magnitude-based inferences and correlation coefficients assessed changes following a 3-month TDE programme. Training elicited meaningful improvements (80-100% likely) in all ergometer parameters. The standing and rolling small gear, track-based effort times were likely and very likely (3.2 ± 2.4% and 3.3 ± 1.9%, respectively) improved by training. Stronger correlations between ergometer- and track-based measures were very likely following training. Ergometer-based testing provides a more sensitive tool than track-based testing to monitor changes in neuromuscular function during the early stages of TDE. However, track-based testing can indicate skill-based improvements in performance when interpreted with ergometer testing. In combination, these tests provide information on overall talent development.