Sprint Cyclists Research Articles

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

ABSTRACT 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.

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

ABSTRACT 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.

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. 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. 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. 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.

Power-duration relationship comparison in competition sprint cyclists from 1-s to 20-min. Sprint performance is more than just peak power.

Current convention place peak power as the main determinant of sprint cycling performance. This study challenges that notion and compares two common durations of sprint cycling performance with not only peak power, but power out to 20-min. There is also a belief where maximal efforts of longer durations will be detrimental to sprint cycling performance. 56 data sets from 27 cyclists (21 male, 6 female) provided maximal power for durations from 1-s to 20-min. Peak power values are compared to assess the strength of correlation (R2), and any relationship (slope) across every level. R2 between 15-s- 30-s power and durations from 1-s to 20-min remained high (R2 ≥ 0.83). Despite current assumptions around 1-s power, our data shows this relationship is stronger around competition durations, and 1-s power also still shared strong relationships with longer durations out to 20-min. Slopes for relationships at shorter durations were closer to a 1:1 relationship than longer durations, but closer to long-duration slopes than to a 1:1 line. The present analyses contradicts both well-accepted hypotheses that peak power is the main driver of sprint cycling performance and that maximal efforts of longer durations out to 20-min will hinder sprint cycling. This study shows the importance and potential of training durations from 1-s to 20-min over a preparation period to improve competition sprint cycling performance.

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).

Force–velocity profiles of track cyclists differ between seated and non-seated positions

ABSTRACT The aim of the study was to compare the Force–Velocity profiles of track sprint cyclists obtained in seated and non-seated positions. Athletes were tested on a stationary cycle ergometer for the seated position and on a racing bike at the velodrome for the non-seated position. We modelled torque and power vs. cadence relationships and extracted maximal force (F0), optimal cadence (Copt), maximal power (Pmax), maximal cadence (C0) and Copt/C0 ratio. Torque/power production was larger in the non-seated position for cadences ranging from 20 to 120 rpm, while more torque and power were produced in the seated position at cadences above 160 rpm. The effective pedal force increased by 0.2 times bodyweight at 50 rpm, and the power production increased by 2.5 W. kg−1 at 90 rpm in the non-seated position. Copt (-14 ± 8 rpm, P < 0.05) and C0 (−55 ± 32 rpm, P < 0.05) were lowered, while Pmax (+1.7 ± 1.1 W. kg−1, P < 0.05) and Copt/C0 ratios (+0.07 ± 0.04, P < 0.05) were increased in the non-seated position when compared with the seated position. Our results show that adopting a non-seated position allows sprint cyclists to maximise torque/power production at lower cadences, while torque/power production was maximised at higher cadences when athletes adopted a seated position.

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

ABSTRACT 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.

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

ABSTRACT 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. Highlights Whilst 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.

Strength capacity of lower-limb muscles in world-class cyclists: new insights into the limits of sprint cycling performance

ABSTRACT This study aimed to determine the relationship between the torque-generating capacity in sprint cycling and the strength capacity of the six lower-limb muscle groups in male and female world-class sprint cyclists. Eleven female and fifteen male top-elite cyclists performed 5-s sprints at maximal power in seated and standing positions. They also performed a set of maximal voluntary ankle, knee and hip flexions and extensions to assess single-joint isometric and isokinetic torques. Isokinetic torques presented stronger correlations with cycling torque than isometric torques for both body positions, regardless of the group. In the female group, knee extension and hip flexion torques accounted for 81.2% of the variance in cycling torque, while the ability to predict cycling torque was less evident in males (i.e., 59% of variance explained by the plantarflexion torque only). The standing condition showed higher correlations than seated and a better predictive model in males (R2 = 0.88). In addition to the knee extensors and flexors and hip extensors, main power producers, the strength capacity of lower-limb distal plantarflexor (and to a lesser extent dorsiflexor) muscles, as well as other non-measured qualities (e.g., the upper body), might be determinants to produce such extremely high cycling torque in males.

Thoracic and Lumbar Sagittal Spinal Curvature Adaptations between Elite Iranian Road and Speed Cyclists.

Background: Despite existing some research on the effects of professional cycling on cyclist’s spinal curvature angles, no research is available concentrating on possible differences in various types of professional cycling. Road (outdoor) and speed (indoor) cyclists have different anthropometric and predominant postures during cycling. The current study aims to investigate if cyclists with different types of cycling may have dissimilar spinal curvature adaptations. Objective: Forty-eight male subjects, including 16 elite road cyclists, 16 elite sprint cyclists and 16 non-athletes as the control group were recruited in this non-experimental study.Material and Methods: In this cross-sectional study, a spinal mouse was used to measure the thoracic and lumbar curvature angles in standing position. Results: The mean values of thoracic kyphosis and lumbar lordosis angles were found as follows 48.3±7.2º & -20.3±7.2º for elite road cyclists; 46.6±8.1º & -22.5±7.7º for elite sprint cyclists; and 37.5±4.1º & -19±6.3º for the control group. The results confirmed that both the road and sprint cyclists showed significantly more hyper-kyphosis posture in their thoracic region when compared to the control group (p<0.05). Conclusion: All road cyclists showed no significantly higher degrees of thoracic angle relative to the sprint cyclists (p>0.05). However, all the cyclists and the control groups showed a normal range of lumbar lordosis angle. As a conclusion, the results of this study confirmed that an elite cyclist may predispose these subjects to the risk of hyper-kyphotic posture. The road cycling may result in more hyper-kyphosis due to the longer time, spent in flexed position.

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

ABSTRACT 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.

Heat Training Improves Cardiovascular Responses And Briefly Blunts Sprint Performance In Elite Sprint Track Cyclists

PURPOSE: To investigate the effects of short-term heat training on sprint performance and cardiovascular function in elite sprint track cyclists. METHODS: Five elite male sprint cyclists (23.8 ± 2.0 years; peak power output = 22.8 ± 1.3 W·kg-1) completed 5 d of training for ~60 min in hot conditions (30-35oC, 40-60% relative humidity (RH)) consisting of sprint-interval training and resistance training. Sprint performance was assessed using an inertial load ergometer in temperate conditions (~20oC, 50% RH) on day 1 and 5 of heat training, and 72 h post. Cardiovascular responses were assessed (~20oC, 50% RH) pre and 24 h post heat training and included a submaximal cycling test and resting plasma volume measurement. During the first (heat training day 1 = HT1) and last (HT5) resistance training session thermoregulatory measurements were recorded. RESULTS: There was a transient decrement in performance as observed by a small very likely decrease in sprint peak power output -4.3% (90% CL -6.1, -2.5)] and small possible decrease [-2.0 rpm (-5.1, 1.2)] at 24 h post heat training. This decrement recovered to baseline within 72 h for both sprint performance (trivial change [0.2% (-3.4, 3.9)]) and optimal cadence (trivial change [-0.8% (-3.5,2.0)]). Core temperature during HT5 was lower (-0.29-0.36oC from 10 to 40 min; small possible decrease) during exercise but there was no effect of heat training on skin temperature or sweat rate compared with baseline values. Following heat training, heart rate during submaximal exercise decreased [-10 bpm (-18, -2); large very likely] and recovery heart rate increased [11 bpm (9, 14); large most likely], compared with baseline values. There was a small likely increase in plasma volume [6.3% (2.7-10.0)] immediate post 5 d HT, compared with baseline values. CONCLUSION: Our findings indicate that markers of cardiovascular stability improved with short-term heat training, and that sprint performance was suppressed at 24 h but rebounded at 72 h post.

Cycling-specific isometric resistance trainingimprovespeak power output in elite sprint cyclists.

This study aimed to assess the efficacy of a 6-week cycling-specific, isometric resistance training program on peak power output (PPO) in elite cyclists. Twenty-four elite track sprint cyclists were allocated to EXP (n=13, PPO, 1537±307W) and CON (n=11, PPO, 1541±389W) groups. All participants completed a 6-week training program; training content was identical except participants in the EXP group replaced their usual compound lower body resistance training exercise with a cycling-specific, isometric resistance training stimulus. Cycling PPO, knee extensor and cycling-specific isometric strength, and measures of muscle architecture were assessed pre- and post-training. In EXP, absolute and relative PPO increased (46±62W and 0.8±0.7W/kg, P<.05), and the change in relative PPO was different to CON (-0.1±1.0W/kg, group×time interaction P=.02). The increase in PPO was concurrent with an increase in extrapolated maximal torque in EXP (7.1±6.5Nm, P=.007), but the effect was not different from the change in CON (2.4±9.7Nm, group×time P=.14). Cycling-specific isometric strength also increased more in EXP (group×time P=.002). There were no other between-group differences in response to training. A 6-week novel, cycling-specific isometric resistance training period improved PPO in a group of elite sprint cyclists by 3%-4%. These data support the use of a cycling-specific isometric resistance training stimulus in the preparation programs of world-class cyclists.

Mechanical and morphological determinants of peak power output in elite cyclists.

Mechanical peak power output (PPO) is a determinant of performance in sprint cycling. The purpose of this study was to examine the relationship between PPO and putative physiological determinants of PPO in elite cyclists, and to compare sprint performance between elite sprint and endurance cyclists. Thirty-five elite cyclists (18 endurance; 17 sprint) performed duplicate sprint cycling laboratory tests to establish PPO and its mechanical components. Quadriceps femoris (QVOL ) and hamstring muscle volume (HAMVOL ) were assessed with MRI, vastus lateralis pennation angle (PθVL ) and fascicle length (FLVL ) were determined with ultrasound imaging, and neuromuscular activation of three muscles was assessed using EMG at PPO during sprint cycling. For the whole cohort, there was a wide variability in PPO (range 775-2025W) with very large, positive, bivariate relationships between PPO and QVOL (r=.87), HAMVOL (r=.71), and PθVL (r=.81). Step-wise multiple regression analysis revealed that 87% of the variability in PPO between cyclists was explained by two variables QVOL (76%) and PθVL (11%). The sprint cyclists had greater PPO (+61%; P<.001 vs endurance), larger QVOL (P<.001), and BFVOL (P<.001) as well as more pennate vastus lateralis muscles (P<.001). These findings emphasize the importance of quadriceps muscle morphology for sprint cycling events.

A wind-tunnel case study: Increasing road cycling velocity by adopting an aerodynamically improved sprint position

The main aim of this study was to evaluate the potential to reduce the aerodynamic drag by studying road sprint cyclists’ positions. A male and a female professional road cyclist participated in this wind-tunnel study. Aerodynamic drag measurements are presented for a total of five out-of-seat sprinting positions for each of the athletes under representative competition conditions. The largest reduction in aerodynamic drag measured for each athlete relative to their standard sprinting positions varied between 17% and 27%. The majority of this reduction in aerodynamic drag could be accounted for by changes in the athlete’s projected frontal area. The largest variation in repeat drag coefficient area measurements of out-of-seat sprint positions was 5%, significantly higher than the typical &lt;0.5% observed for repeated testing of time-trial cycling positions. The majority of variation in repeated drag coefficient area measurements was attributed to reproducibility of position and sampling errors associated with time-averaged force measurements of large fluctuating forces.

Comparing physique with physical fitness based on muscle strength and power in short middle, and long-distance elite cyclists

Purpose This study was conducted to analyze the differences of physical characteristics focused on the physique, strength, and power for cycling national athletes (Sprint cyclists and Road race cyclists). Methods We measured various factors (e.g., height, weight, body fat ratio, thigh circumference, waist circumference, anaerobic power, isokinetic muscular strength, muscle power, squat jump by 1RM intensity, and so on) for a total 11 male cycling national athletes (5 Sprint cyclists and 6 Road race cyclists). Results First, the body composition showed the significant differences only in weight (p=0.31) and BMI (p=.001) for Sprint cyclists. Second, the values of the anaerobic power for the Sprint cyclists were significantly higher than those for the Road race cyclists only at peak power (p=0.28), whereas there was no significant difference in average power, isokinetic muscular strength, and muscle power between the two groups. Third, the isokinetic trunk flexion muscle (p = .016) for the Sprint cyclists were significantly higher than those for the Road race cyclists. Fourth, the significant difference in Time to Peak Torque was not found between two groups. Fifth, the values for the Sprint cyclists showed the significant difference in all 5 intensity groups (0%, 30%, 50%, 60%, and 80%) (p=.001) of the squat jump. Also, there was a statistically significant difference only in 0% velocity between the two groups, except for exercise intensity. Conclusions From the various measures between two groups, the Sprint cyclists relatively showed the high weight, BMI (muscle mass), and maximum power. Additionally, the isokinetic trunk flexion muscle and the squat jump were higher in the Sprint cyclists than the Road race cyclists. These data may be used as basic data to improve the physical fitness factors related to the athletic performance of the athletes by reflecting them in the effective training plan and evaluation of the athletes.

Relation between maximal power in sprint cycling, pedal force orientation and strength of the lower limb muscles in elite sprint cyclists

The aim of this study was to determine, in a high-level population, how the maximal power produced during pedalling relates to the capacity to orient the pedal force, and to the force-generating capacity of the six main muscle groups of the lower limb, and whether this relationship is improved by using specific velocity conditions during single-joint strength measurements. 19 high-level cyclists performed two separated sessions : first, maximal power during pedalling was assessed while strength capacities were assessed in different force-velocity conditions. Results suggest that assessing single-joint strength at specific velocities is more relevant, and this, particularly in the extension phase. In the flexion phase, the power produced is largely influenced by the capacity to effectively orientate the force on the pedals.

Potentiation of sprint cycling performance: the effects of a high-inertia ergometer warm-up

ABSTRACTParticipant and protocol factors affect post-activation potentiation response. Performance enhancement is more consistent in highly-trained participants following multiple sets of a biomechanically similar conditioning activity. Providing optimal conditions, 6 international-level sprint cyclists executed multiple sets of short maximal conditioning contractions on a high-inertia ergometer before metered sprint performance. Three trial conditions were completed on separate days after a standardised warm-up: dynamic (DYN: 4 × 4 crank-cycles), isometric (ISO: 4 × 5-sec maximal voluntary contraction (MVC)), and control (CON: rest). Performance was measured from standing start to maximum velocity on an inertial-load ergometer at baseline (Pre), 4 (Post4), 8 (Post8) and 16 (Post16) min post-conditioning. Performance and biomechanical measures were assessed across 4 sprint segments, with magnitude-based inferences used to assess the likelihood that any affect was beneficial. Performance time only improved in DYN Post4, a 3.9% reduction during the first crank cycle (92% likely). On the ascending limb of the power-cadence relationship, peak torque and average power increased by 6.2% (94% likely) and 4.0% (87% likely), respectively. In ISOPost16, optimal cadence increased (82% likely) and average power improved over the descending limb (76% likely). DYN and ISO potentiated extremities of the torque-cadence relationship at distinct recovery times post-conditioning. This study suggests merit in including a high-inertia warm-up for sprint cycling.

Agreement between LeMond Revolution cycle ergometer and SRM power meter during power profile and ramp protocol assessments

This study aimed to evaluate the agreement in cycling power output measurements between the LeMond Revolution cycle ergometer and SRM power meter. The LeMond Revolution measures power output via removal of the rear bicycle wheel and attaching it using a quick-release system, estimating power output through a head-unit that processes drive-train resistance and atmospheric conditions. Fourteen well-trained cyclists completed incremental protocols and power profile assessments on a bicycle fitted with SRM scientific power meter and attached to a LeMond Revolution cycle ergometer. Power output was measured by both devices at 1 Hz. Data from each device were compared using Pearson’s correlations, paired t-tests, assessments of heteroscedasticity, Bland-Altman plots and 95% limits of agreement. During incremental tests, errors in power measurement of the LeMond Revolution progressively increased at greater power outputs when compared with SRM (bias: 2-34 W; CV 1.5-6.7%). During power profile assessments, errors in mean power measurement of the LeMond Revolution were also slightly overestimated for all efforts from a rolling start (+3 ± 8%; CV = 5.1%). Conversely, the LeMond Revolution underestimated peak power output during five second sprint efforts and the greatest error was observed between measurements for mean power output during a five second sprint from a stationary start (-7 ± 24%; CV = 10.6%). Overall, the LeMond Revolution is a practical, cost-effective alternative to more expensive ergometers for detecting large changes in mean power output. However, high level of error during high-intensity sprint efforts from a stationary start is a limitation for well-trained sprint cyclists.

Potentiation of sprint cycling performance: the effects of a high-inertia ergometer warm-up

Background: Individual response to acute post-activation potentiation (PAP) stimulation is affected by factors such as the conditioning protocol design, training status, and biomechanical similarity of the conditioning activity to the goal movement. Purpose: This study tested the effect of a biomechanically comparable PAP conditioning activity on various aspects of standing start sprint cycling performance. Optimal conditions for observing PAP were provided by utilising highly-trained sprint cycling-athletes and a commonly successful protocol executed on a specially built high-inertia cycle ergometer. Methods: Employing a randomized, counterbalanced, cross-over design with repeated measures, four male and two female national and international competitive sprint cyclists (19.2  3.2; mean  s yrs; height 175.2  7.0 cm; body mass 75.5  9.8 kg; training years (sprint cycling) 4.0  1.5 years; training years (strength) 3.5  1.2 years; peak isometric pedal torque 255.9  37.8 Nm) executed multiple sets of short maximal conditioning contractions (CC) on a custom-built high-inertia ergometer prior to metered sprint performance. Three trial conditions were completed on three separate days: a standardised warm-up followed by either dynamic (DYN: 4 x 4 complete crank cycles), or isometric (ISO: 4 x 5-second MVC) CC, or a control condition (CON) with active rest for the total equivalent time post-warm-up. Performance was assessed in a short (~6 seconds) maximal acceleration from standing start to maximum velocity on an inertial-load ergometer at baseline (Pre), 4 (Post4), 8 (Post8) and 16 (Post16) minutes following the CC protocol. Torque-cadence and power-cadence relationships were derived from crank data. Performance time, and peak and average biomechanical measures were assessed over four discrete sprint segments. Outcomes were assessed using 2-way repeated measures ANOVA and magnitude-based inferences. Results: Only in DYN Post4 was performance time improved, affecting a 3.9 ± 3.7% (92% likelihood of exceeding smallest worthwhile change (SWC)) decrease in time over the first segment of the sprint. Biomechanical improvements in this trial were predominantly on the ascending limb of the power-cadence relationship, increasing peak torque by 6.2 ± 5.9% (94% SWC) and increasing average power during initial acceleration by 4.0 ± 6.5% (87% SWC). Conversely, ISO Post16 enhanced performance over the descending limb of the power-cadence relationship, affecting an increase in optimal cadence (82% SWC) and augmenting average power (76% SWC) during the maximal velocity phase of the sprint. Discussion: The dynamic and isometric trials contrasted in potentiating opposite extremities of the torque-cadence relation at distinct recovery-times post-CC. Results suggest the predominance of different PAP mechanisms in each trial condition. Conclusion: This study provisionally suggests merit in including a high-inertial component in the sprint warm-up. Performance improvements may include improved starting acceleration or finishing speed, where compromise in gear and pedal length selection strategies would, otherwise, impose limitations on performance.