Cycling‐specific isometric resistance training improves peak power output in elite sprint cyclists

Off- and On-Bike Resistance Training in Cyclists: A Randomized Controlled Trial

PURPOSE

This study compared the effects of off- and on-bike resistance training (RT) on endurance cycling performance as well as muscle strength, power, and structure.

METHODS

Well-trained male cyclists were randomly assigned to incorporate two sessions/week of off-bike (full squats, n = 12) or on-bike (all-out efforts performed against very high resistances and thus at very low cadences, n = 12) RT during 10 wk, with all RT-related variables (number of sessions, sets, and repetitions, duration of recovery periods, and relative loads [70% of one-repetition maximum]) matched between the two groups. A third, control group ( n = 13), did not receive any RT stimulus, but all groups completed a cycling training regime of the same volume and intensity. Outcomes included maximum oxygen uptake (V̇O 2max ), off-bike muscle strength (full squat) and on-bike ("pedaling") muscle strength, and peak power capacity (Wingate test), dual-energy X-ray absorptiometry-determined body composition (muscle/fat mass), and muscle structure (cross-sectional area, pennation angle).

RESULTS

No significant within/between-group effect was found for V̇O 2max . Both the off-bike (mean Δ = 2.6%-5.8%) and on-bike (4.5%-7.3%) RT groups increased squat and pedaling-specific strength parameters after the intervention compared with the control group (-5.8% to -3.9%) ( P < 0.05) with no significant differences between them. The two RT groups also increased Wingate performance (4.1% and 4.3%, respectively, vs -4.9% in the control group, P ≤ 0.018), with similar results for muscle cross-sectional area (2.5% and 2.2%, vs -2.3% in the control group, P ≤ 0.008). No significant within/between-group effect was found for body composition.

CONCLUSIONS

The new proposed on-bike RT could be an effective alternative to conventional off-bike RT training for improving overall and pedaling-specific muscle strength, power, and muscle mass.

Examining the Effects of Dynamic and Isometric Resistance Training on Knee Joint Kinetics During Unplanned Sidesteps in Elite Female Athletes

ABSTRACT

Kadlec, D, Jordan, MJ, Alderson, J, and Nimphius, S. Examining the effects of dynamic and isometric resistance training on knee joint kinetics during unplanned sidesteps in elite female athletes. J Strength Cond Res 38(12): 2079-2087, 2024-The purpose of this study was to examine the effects of a 4-week block of isometric (isometric RT ) and dynamic resistance training (dynamic RT ) on kinetic variables associated with anterior cruciate ligament (ACL) injury risk during unplanned sidesteps in elite female athletes. Twenty-one elite female athletes competing for a women's international rugby union team were recruited with 15 ( n = 15; age: 23.4 ± 4.7 years; 170.7 ± 8.4 cm; 84.4 ± 15.4 kg) completing assessment of knee flexion moment, knee valgus moment (KVM), knee internal rotation moment (KIRM), knee joint power during unplanned sidesteps, and lower limb strength before and after a 4-week intervention. Linear mixed effects models and one-dimensional statistical parametric mapping assessed the effect of the interventions. Statistical significance was set at α = 0.05. Postintervention the isometric RT group revealed reduced peak KVM during early stance ( p = 0.04) while the dynamic RT group decreased peak KIRM ( p < 0.01) and KIRM over 8.8-86.6% ( p < 0.01) and 96.9-98.5% ( p = 0.047). An exploratory combined group analysis revealed reductions in KVM over 7.9-21.8% ( p = 0.002) and in KIRM over 8.3-90.5% ( p < 0.01) and 96.2-98.5% ( p = 0.046). Most lower limb isometric and dynamic strength measures increased after both resistance training interventions. Overall, both groups increased lower-body maximum strength while reducing kinetic knee joint variables associated with ACL injury risk during unplanned sidesteps. These results highlight the importance of increasing single-joint and multijoint strength in female athletes to mitigate the mechanical knee joint demands during sidestepping.

Change in sprint cycling torque is not associated with change in isometric force following six weeks of sprint cycling and resistance training in strength-trained novice cyclists

Strong relationships exist between sprint cycling torque and isometric mid-thigh pull (IMTP) force production at one timepoint; however, the relationships between the changes in these measures following a training period are not well understood. Accordingly, this study examined the relationships in the changes of sprint cycling torque and IMTP force following six-weeks of sprint cycling and resistance training performed by strength-trained novice cyclists (n = 14). Cycling power, cadence, torque and IMTP force (Peak force [PF]/torque, average and peak rate of force/torque development [RFD/RTD], and RFD/RTD from 0 to 100 ms and 0-200 ms) were assessed before and after training. Training consisted of three resistance and three sprint cycling sessions per week. Training resulted in improvements in IMTP PF (13.1%) and RFD measures (23.7%-32.5%), cycling absolute (10.7%) and relative (10.5%) peak power, peak torque (11.7%) and RTD measures (27.9%-56.7%). Strong-to-very strong relationships were observed between cycling torque and IMTP force measures pre- (r = 0.57-0.84; p < 0.05) and post-training (r = 0.63-0.87; p < 0.05), but no relationship (p > 0.05) existed between training-induced changes in cycling torque and IMTP force. Divergent training-induced changes in sprint cycling torque and IMTP force indicate that these measures assess distinct neuromuscular attributes. Training-induced changes in IMTP force are not indicative of training-induced changes in sprint cycling torque.

The effects of different post-activation potentiation strategies on the performance of elite female track cyclists in position 1 of team sprint

The study aimed to optimise post-activation potentiation (PAP) strategies for Rider 1 in elite team sprints to improve performance over 250 m (opening lap), with a focus on female cyclists. Eight national-level track cyclists participated in this study, undergoing four sets of activation strategies: control (CON), dynamic high inertia (DYN, 4 × 4 pedal strokes), isometric contraction (ISO, 4 × 4 s, 4 angles), and back squat activation (BSQ, 4 × 4 rep, 80%1RM). The tests were divided into pre-activation and post-activation phases, including measurements at 4 min, 8 min, and 12 min after activation. The tests included a 250 m time trial (TT) and segment timing, with measurements of peak torque, peak power, average power, and cadence. The mean cadence, torque, and power for the first 62.5 m of pedal revolutions were collected. Paired-sample t-tests were used to assess activation differences. Multiple group comparisons were conducted using analysis of variance (ANOVA). The Bonferroni correction was used to control Type I errors. For significant activation strategies, linear or non-linear regression was applied to extrapolate the torque-cadence and power-cadence profiles, and the parameter differences were examined to investigate profile changes. Cohen's d and Cohen's f were used as effect sizes. After DYN activation, the 250 m TT significantly improved (p = 0.018), primarily through a reduction in the 62.5 m time (p = 0.006) and an increase in peak torque (p = 0.018). After 12 min of ISO activation, the 250 m TT showed a large effect but did not reach the significance level under Bonferroni correction (p = 0.135, d = 0.860), with a notable reduction in the 62.5 m time (p = 0.003). PAP can be strategically employed to enhance the performance of elite female Rider 1 in team sprints.

Performance analysis and mechanical determinants of the opening lap of the team sprint in elite-level track cycling

The team sprint (TS) is a three-lap pursuit and the most revered event in track sprint cycling. The opening lap of the TS is an important determinant to the overall performance. But despite it being the most controlled and repeatable task in track sprint cycling, very little data are available to better understand the performance of the opening lap. The aim of this study was split into three-parts: part one, to better understand the profile and the indices thought to be determinants of the opening lap of the TS in elite sprint track cyclists. Part two of the study examined all available timing splits (15, 65, 125 and 250 m) from 36 standing-start laps. Part three of the study examined the peak torque outputs and peak power outputs of different various starts performed over a 3-month period. The results showed time to 125 m exhibited a near perfect relationship with starter lap performance. Very strong relationships were seen with 15 and 65 m split times and final lap performance. Peak torque of the lead starting leg and peak power output were shown to be highly predictive 15 m, 65 and 125 m performance in training. These data suggested the first 15 m is highly important and predicts a disproportionately high level of final opening lap time performance. Therefore, it is likely that peak power output normalised to system mass and peak torque of lead leg is a strong determinant of overall performance in the TS.

The relationship between bone parameters, body composition, and lower extremity strength in road cyclists

BACKGROUND

This study aimed to compare the relationships between bone and body composition parameters, and isometric maximal voluntary contraction (MVC) force of knee extensor (KE) muscles in road cyclists and untrained controls.

METHODS

Twelve male road cyclists and 12 controls aged 20-34 years participated. The isometric MVC force of the KE muscles was assessed by a custom-made dynamometer. Bone mineral content (BMC), bone mineral density (BMD), and body composition were assessed using Dual-Energy X-ray Absorptiometry.

RESULTS

No differences were found in body mass, lean body mass, leg lean mass, MVC, whole body, and leg BMD and BMC between cyclists and controls. Controls had a significantly greater (P<0.001) body mass index (BMI), whole body (P<0.01), and leg fat (P<0.001) mass than athletes. In road cyclists, BMC correlated positively with body mass (r=0.73; P<0.01) and BMI (r=0.65; P<0.05), body (r=0.85; P<0.001) and leg lean mass (r=0.81; P<0.001); BMD correlated positively with lean body mass (r=0.60; P<0.05), leg lean mass (r=0.65 and r=0.60; P<0.05). MVC of KE muscles correlated positively with bone parameters (P<0.01) and lean mass (P<0.05) only in controls.

CONCLUSIONS

Regular cycling training was associated with lower BMI, and body and leg fat mass. There were no significant differences in bone parameters, body and leg lean mass, and isometric MVC force of KE muscle variables between road cyclists and controls. In road cyclists, bone parameters are associated with body mass, and body and leg lean mass, but not with the isometric strength of KE muscles.

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.

The Efficacy of Chlorella Supplementation on Multiple Indices of Cycling Performance

This study investigated the effects of chlorella supplementation on submaximal endurance, time trial performance, lactate threshold, and power indices during a repeated sprint performance test by fourteen male trained cyclists. Participants ingested 6 g/day of chlorella or placebo for 21-days in a double-blinded randomized counter-balanced cross-over design, with a fourteen-day washout period between trials. Each completed a 2-day testing period comprising a 1-hour submaximal endurance test at 55% external power output max and a 16.1 km time trial (Day-1), followed by a lactate threshold (Dmax) and repeated sprint performance tests (3 X 20 s sprints interspersed by 4-mins) (Day-2). Heart rate (b.min-1), RER, V̇O2 (ml·kg-1·min-1), lactate and glucose (mmol/L), time (secs), power output (W/kg), and hemoglobin (g/L) were compared across conditions. Following chlorella supplementation (chlorella vs. placebo for each measurement) average lactate and heart rate were significantly lower (p < 0.05) during submaximal endurance tests (1.68 ± 0.50 mmol/L vs. 1.91 ± 0.65 mmol/L & 138 ± 11b.min-1 vs. 144 ± 10b.min-1), average power and peak power (W/kg) were significantly higher during repeated sprint bouts (9.5 ± 0.7 W/kg vs. 9.0 ± 0.7 W/kg & 12.0 ± 1.2 W/kg vs. 11.4 ± 1.4 W/kg), hemoglobin significantly increased (149.1 ± 10.3 g/L) in comparison to placebo (143.4 ± 8.7 g/L) (p = 0.05). No differences existed between conditions for all oxygen consumption values, 16.1 km time trial measures and lactate threshold tests (p > 0.05). In conclusion, chlorella may pose as an additional supplement for cyclists to consider, particularly for those cyclists who want to improve their sprinting.

Sprint cycling rate of torque development associates with strength measurement in trained cyclists

PURPOSE

A cyclist's rate of force/torque development (RFD/RTD) and peak force/torque can be measured during single-joint or whole-body isometric tests, or during cycling. However, there is limited understanding of the relationship between these measures, and of the mechanisms that contribute to each measure. Therefore, we examined the: (i) relationship between quadriceps central and peripheral neuromuscular function with RFD/RTD in isometric knee extension, isometric mid-thigh pull (IMTP), and sprint cycling; and (ii) relationship among RFD/RTD and peak force/torque between protocols.

METHODS

Eighteen trained cyclists completed two familiarisation and two experimental sessions. Each session involved an isometric knee extension, IMTP, and sprint cycling protocol, where peak force/torque, average and peak RFD/RTD, and early (0-100 ms) and late (0-200 ms) RFD/RTD were measured. Additionally, measures of quadriceps central and peripheral neuromuscular function were assessed during the knee extension.

RESULTS

Strong relationships were observed between quadriceps early EMG activity (EMG₅₀/M) and knee extension RTD (r or ρ = 0.51-0.65) and IMTP late RFD (r = 0.51), and between cycling early or late RTD and peak twitch torque (r or ρ = 0.70-0.75). Strong-to-very strong relationships were observed between knee extension, IMTP, and sprint cycling for peak force/torque, early and late RFD/RTD, and peak RFD/RTD (r or ρ = 0.59-0.80).

CONCLUSION

In trained cyclists, knee extension RTD or IMTP late RFD are related to measures of quadriceps central neuromuscular function, while cycling RTD is related to measures of quadriceps peripheral neuromuscular function. Further, the strong associations among force/torque measures between tasks indicate a level of transferability across tasks.

Comparing the Effects of Long-Term vs. Periodic Inclusion of Isometric Strength Training on Strength and Dynamic Performances

ABSTRACT

Lum, D, Joseph, R, Ong, KY, Tang, JM, and Suchomel, TJ. Comparing the effects of long-term vs. periodic inclusion of isometric strength training on strength and dynamic performances. J Strength Cond Res 37(2): 305-314, 2023-This study compared the effects of including isometric strength training (IST) for consecutive 24 weeks (CIST) against a periodic inclusion (PIST) of this mode of training on strength and dynamic performances. Twenty-four floorball athletes (age: 23 ± 2.7 years, stature: 1.74 ± 2.08 m, and body mass: 72.7 ± 14.4 kg) were randomly assigned to the control (CON), CIST, or PIST group. Athletes completed 20-m sprint, countermovement jump (CMJ), and isometric midthigh pull (IMTP) during pre-test and were tested on weeks 6, 12, 18, and 24. All groups performed a similar strength training program twice per week. However, 2 sets of squats were replaced with isometric squat in CIST for all 24 weeks but only on weeks 1-6 and 13-18 for PIST. A significant main effect for time was observed for 5-, 10-, and 20-m sprint time, CMJ height, peak force, peak power, time to take-off, modified reactive strength index, IMTP peak force, relative peak force, and force at 200 milliseconds ( p = <0.001-0.037). Isometric strength training for 24 consecutive weeks resulted in greater improvement in 5-m sprint time than CON at week 24 ( p = 0.024, g = 1.17). Both CIST and PIST resulted in greater improvements in 10-m sprint time than CON at various time points ( p = 0.007-0.038 and 0.038, g = 1.07-1.44 and 1.18, respectively). Isometric strength training for 24 consecutive weeks and PIST resulted in greater improvements in 20-m sprint time than CON at week 6 ( p = 0.007 and 0.025, g = 1.65 and 1.40, respectively). The results showed that the inclusion of IST resulted in greater improvements in sprint performance than CON but no significant difference in all measured variables with PIST.

Influence of Torque and Cadence on Power Output Production in Cyclists

PURPOSE

No information is available on the torque/cadence relationship in road cyclists. We aimed to establish whether this relationship differs between cyclists of different performance levels or team roles.

METHODS

Mean maximal power (MMP) output data from 177 riders were obtained from 2012 to 2021 from training and competitions. Cyclists were categorized according to their performance level (world-tour [WT, n = 68], procontinental [PC, n = 63], or under 23 [U23, n = 46]) and team role (time trialists [n = 12], all-rounders [n = 94], climbers [n = 64], or team leaders [n = 7]).

RESULTS

A significant interaction effect was found for absolute and relative MMP (P < .001), with higher values in PC than WT for short (5-60 s) efforts and the opposite trend for longer durations. MMP was also greater in PC than in U23 for short efforts (30-60 s), with WT and PC attaining higher MMP than U23 for longer bouts (5-60 min). A significant interaction effect was found for cadence (P = .007, but with no post hoc differences) and absolute (P = .010) and relative torque (P = .002), with PC and WT showing significantly higher torque (all P < .05) than U23 for 5- to 60-minute efforts, yet with no differences between the former 2 performance levels. No interaction effect between team roles was found for cadence (P = .185) or relative torque (P = .559), but a significant interaction effect was found for absolute torque (P < .001), with all-rounders attaining significantly higher values than climbers for 5-second to 5-minute efforts.

CONCLUSIONS

Differences in MMP between cycling performance levels and rider types are dependent on torque rather than cadence, which might support the role of torque development in 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).

Comparative analysis of endurance, strength and body composition indicators in professional, under-23 and junior cyclists

Purpose: To compare endurance, strength and body composition indicators between cyclists of three different competition age categories.

Methods: Fifty-one male road cyclists classified as either junior (n = 13, age 16.4 ± 0.5 years), under-23 [(U23), n = 24, 19.2 ± 1.3 years] or professional (n = 14, 26.1 ± 4.8 years) were studied. Endurance (assessed through a maximal incremental test and an 8-minute time-trial), strength/power (assessed through incremental loading tests for the squat, lunge and hip thrust exercises) and body composition (assessed through dual energy X-ray absorptiometry) were determined on three different testing sessions.

Results: U23 and, particularly professional, cyclists attained significantly (p < 0.05) higher values than juniors for most of the analyzed endurance indicators [time-trial performance, maximum oxygen uptake (VO_2max), peak power output (PPO), respiratory compensation point (RCP), and ventilatory threshold (VT)]. Significant differences (p < 0.05) between U23 and professionals were also found for time-trial performance, PPO and VT, but not for other markers such as VO_2max or RCP. Professional cyclists also showed significantly (p < 0.05) lower relative fat mass and higher muscle mass levels than U23 and, particularly, juniors. No consistent differences between age categories were found for muscle strength/power indicators.

Conclusion: Endurance (particularly time-trial performance, PPO and VT) and body composition (fat and muscle mass) appear as factors that best differentiate between cyclists of different age categories, whereas no consistent differences are found for muscle strength/power. These findings might help in performance prediction and/or talent identification and may aid in guiding coaches in the design of training programs focused on improving those variables that appear more determinant.

Field-testing to determine power - cadence and torque - cadence profiles in professional road cyclists

AbstractThe aim of this study was to evaluate a field-based approach to determine torque-cadence and power-cadence profiles in professional cyclists and establish if this field-based protocol can differentiate between varying rider specializations. Twenty-four male professional athletes from a World Tour cycling team participated in this investigation (Height = 1.84 ± 0.05 m, Weight = 72.3 ± 5.6 kg, Age = 25 ± 4 y). All riders were subsequently categorized into the following groups: 1) General Classification (GC) group; 2) sprinter group; and 3) classics group. All participants completed a specific sprint protocol in the field which included 6 times 6s sprints with varying gearing, starting cadences, starting speeds and position (i.e. seated vs standing). Power-cadence and torque-cadence profiles were determined based on the sprint outputs. There was a significant main effect of rider specialization on the measured (sprint) variables (P≤0.03). Body weight, maximum power outputs (1s, 10s and modelled) and maximum torque were highest in the sprinter group, followed by the classics group, followed by the GC group. The protocol was able to differentiate between different rider specializations (i.e. GC, sprinters, classics). The proposed methodology can contribute to individualizing training content in the short-duration domain.

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.

Effects of Performing Isometric Bench Press Training at Single Versus Multiple Joint Positions on Strength and Power Performance

Isometric strength training has been reported to benefit various sport-related dynamic performances. However, it is still unknown whether performing isometric strength training at single or multiple joint angles would elicit greater benefit.

PURPOSE

To compare the effects of isometric bench press performed at single (SIBP) and multiple (MIBP) joint angles on dynamic strength and overhead throwing performance.

METHODS

Sixteen male softball and baseball athletes performed overhead throwing, 1-repetition-maximum (1RM) bench press, and ballistic push-up during pretest and posttest. They were then randomly assigned to either SIBP or MIBP to undergo 12 strength training sessions. During the training, isometric bench press was performed at only 90° elbow angle for SIBP but at 60°, 90°, and 120° elbow angles for MIBP.

RESULTS

A significant main time effect was observed for bench press 1RM (P = .003) and relative 1RM (P < .001). Similarly, a significant main time effect was observed for ballistic push-up peak power only (P = .037). There was no significant change in overhead throwing velocity in either group. There was also no significant difference in change in all measures between groups. However, a moderate effect in favor of MIBP was observed for change in ballistic push-up peak power (P = .180, g = 0.67).

CONCLUSIONS

Based on the current findings, the inclusion of both SIBP and MIBP were equally beneficial to maximal strength development. However, performing MIBP had a greater effect on power development.

Power attenuation from restricting range of motion is minimized in subjects with fast RTD and following isometric training

Time-dependent measures consisting of rate of torque development (RTD), rate of velocity development (RVD), and rate of neuromuscular activation can be used to evaluate explosive muscular performance, which becomes critical when performing movements throughout limited ranges of motion (ROM). Using a HUMAC NORM dynamometer, seven males (27 ± 7 years) and six females (22 ± 3 years) underwent 8 weeks of maximal isometric dorsiflexion training 3 days/week. One leg was trained at 0° (short-muscle tendon unit (MTU) length) and the other at 40° of plantar flexion (long-MTU length). RTD and rate of neuromuscular activation were evaluated during 'fast' maximal isometric contractions. Power, RVD, and rate of neuromuscular activation were assessed during maximal isotonic contractions in four conditions (small (40° to 30° of plantar flexion) ROM at 10 and 50% MVC; large (40° to 0° of plantar flexion) ROM at 10 and 50% MVC) for both legs, pre- and post-training. Despite no change in rate of neuromuscular activation following training, peak power, RTD, and RVD increased at both MTU lengths (p < 0.05). Strong relationships (R²=0.73) were observed between RTD and peak power in the small ROM, indicating that fast time-dependent measures are critical for optimal performance when ROM is constrained. Meanwhile, strong relationships (R²=0.90) between RVD and power were observed at the 50% load, indicating that RVD is critical when limited by load and ROM is not confined. Maximal isometric dorsiflexion training can be used to improve time-dependent measures (RTD, RVD) to minimize power attenuation when ROM is restricted.

Comparing the effects of plyometric and isometric strength training on dynamic and isometric force-time characteristics

The purpose of the study was to compare the change in dynamic and isometric force-time characteristics after plyometric (PLYO) or isometric strength training (ISO). Twenty-two endurance runners (age = 37 ± 6 years, stature = 1.71 ± 0.05 m, body mass = 62.7 ± 8.6 kg, weekly mileage = 47.3 ± 10.8 km) performed a countermovement jump (CMJ) and isometric mid-thigh pull (IMTP) test during pre- and post-tests. They were then randomly assigned to either PLYO or ISO group and completed 12 sessions of intervention over six weeks. The PLYO included drop jump, single leg bounding and split jump, and the ISO included IMTP and isometric ankle plantar flexion. Significant and large time x group interactions were observed for CMJ countermovement depth (P = 0.037, ƞ²_p = 0.21) and IMTP and relative peak force (PF) (P = 0.030, ƞ^² _p = 0.22). Significant and large main effects for time were observed in CMJ height, peak power, propulsive phase duration, countermovement depth, reactive strength index modified, IMTP PF and relative PF (P < 0.05, 0.20 ≤ ƞ²_p ≤ 0.65). Effect for time showed small improvement in CMJ height for both PLYO (P < 0.001, d = 0.48) and ISO (P = 0.009, d = 0.47), small improvement in CMJ PP in PLYO (P = 0.020, d = 0.21), large increase in countermovement depth (P = 0.004, d = 1.02) and IMTP relative PF (P < 0.001, d = 0.87), and moderate increase in propulsive phase duration (P = 0.038, d = 0.65) and IMTP PF (P < 0.001, d = 0.55) in ISO. There were large differences between groups for percentage change in countermovement depth (P = 0.003, d = 0.96) and IMTP relative PF (P = 0.047, d = 0.90). In conclusion, both PLYO and ISO improved CMJ jump height via different mechanisms, while only ISO resulted in improved IMTP PF and relative PF.

Testing, Training, and Optimising Performance of Track Cyclists: A Systematic Mapping Review

Background

Track cyclists must develop mental, physical, tactical and technical capabilities to achieve success at an elite level. Given the importance of these components in determining performance, it is of interest to understand the volume of evidence to support implementation in practice by coaches, practitioners, and athletes.

Objective

The aim of this study was to conduct a systematic mapping review to describe the current scale and density of research for testing, training and optimising performance in track cycling.

Methods

All publications involving track cyclist participants were reviewed from four databases (PubMed, SPORTDiscus, Academic Search Complete, Cochrane Library) plus additional sources. Search results returned 4019 records, of which 71 met the inclusion criteria for the review.

Results

The review revealed most published track cycling research investigated athlete testing followed by performance optimisation, with training being the least addressed domain. Research on the physical components of track cycling has been published far more frequently than for tactical or technical components, and only one study was published on the mental components of track cycling. No true experimental research using track cyclists has been published, with 51 non-experimental and 20 quasi-experimental study designs.

Conclusions

Research in track cycling has been growing steadily. However, it is evident there is a clear preference toward understanding the physical—rather than mental, tactical, or technical—demands of track cycling. Future research should investigate how this aligns with coach, practitioner, and athlete needs for achieving track cycling success.

Registration

This systematic mapping review was registered on the Open Science Framework (osf.io/wt7eq).

Supplementary Information

The online version contains supplementary material available at 10.1007/s40279-021-01565-z.

Twenty-one days of spirulina supplementation lowers heart rate during submaximal cycling and augments power output during repeated sprints in trained cyclists

Spirulina supplementation has been reported to improve time to exhaustion and maximal oxygen consumption (V̇O2max). However, there is limited information on its influence over the multiple intensities experienced by cyclists during training and competition. Fifteen trained males (age 40 ± 8 years, V̇O2max 51.14 ± 6.43 mL/min/kg) ingested 6 g/day of spirulina or placebo for 21 days in a double-blinded randomised crossover design, with a 14-day washout period between trials. Participants completed a 1-hour submaximal endurance test at 55% external power output max and a 16.1-km time trial (day 1), followed by a lactate threshold test and repeated sprint performance tests (RSPTs) (day 2). Heart rate (bpm), respiratory exchange ratio, oxygen consumption (mL/min/kg), lactate and glucose (mmol/L), time (seconds), power output (W), and hemoglobin (g/L) were compared across conditions. Following spirulina supplementation, lactate and heart rate were significantly lower (P < 0.05) during submaximal endurance tests (2.05 ± 0.80 mmol/L vs 2.39 ± 0.89 mmol/L and 139 ± 11 bpm vs 144 ± 12 bpm), hemoglobin was significantly higher (152.6 ± 9.0 g/L) than placebo (143.2 ± 8.5 g/L), and peak and average power were significantly higher during RSPTs (968 ± 177 W vs 929 ± 149 W and 770 ± 117 W vs 738 ± 86 W). No differences existed between conditions for all oxygen consumption values, 16.1-km time trial measures, and lactate threshold tests (P > 0.05). Spirulina supplementation reduces homeostatic disturbances during submaximal exercise and augments power output during RSPTs. Novelty: Spirulina supplementation lowers heart rate and blood lactate during ∼1-hour submaximal cycling. Spirulina supplementation elicits significant augmentations in hemoglobin and power outputs during RSPTs.

Early Specialization and Critical Periods in Acquiring Expertise: A Comparison of Traditional Versus Detection Talent Identification in Team GB Cycling at London 2012

The aim of this study was to compare two methodologies employed by the British Cycling talent identification program. Specifically, the authors investigated cyclists selected to represent GB cycling team at the London 2012 Olympics using (a) a traditional talent identification methodology (British Cycling Olympic Development Program), where selection is based upon race results and (b) a detection talent identification methodology (U.K. Sport Talent Team Program), which is a multi-Olympic event initiative that identifies athletic potential from physical and skill-based tests. To facilitate this comparison, the authors calculated the speed with which expertise was acquired. A Mann–Whitney U test (U = 16.0, p = .031) indicated that the speed of acquiring expertise was quicker in detection talent identification (Mdn = 5.4) than traditional talent identification (Mdn = 7.2). Practice started later with detection talent identification than with traditional talent identification (14.12 years vs. 11.23 years, respectively), which affected the period to excellence. Thus, detection talent identification resulted in an absence of early specialization, which suggests a critical period for attaining cycling expertise. The authors hypothesize a genetic basis of talent and propose that critical periods are important in detection talent identification programs.

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.

The Relationship Between Neuromuscular Function and the W' in Elite Cyclists

PURPOSE

To assess the association between the W' and measures of neuromuscular function relating to the capacity of skeletal muscle to produce force in a group of elite cyclists.

METHODS

Twenty-two athletes specializing in a range of disciplines and competing internationally volunteered to participate. Athletes completed assessments of maximum voluntary torque (MVT), voluntary activation, and isometric maximum voluntary contraction to measure rate of torque development (RTD). This was followed by assessment of peak power output (PPO) and 3-, 5-, and 12-minute time trials to determine critical power. Pearson correlation was used to examine associations with critical power and W'. Goodness of fit was calculated, and significant relationships were included in a linear stepwise regression model.

RESULTS

Significant positive relationships were evident between W' and MVT (r = .82), PPO (r = .70), and RTD at 200 milliseconds (r = .59) but not with RTD at 50 milliseconds and voluntary activation. Correlations were also observed between critical power and RTD at 200 milliseconds and MVT (r = .54 and r = .51, respectively) but not with PPO, voluntary activation, or RTD at 50 milliseconds. The regression analysis found that 87% of the variability in W' (F1,18 = 68.75; P < .001) was explained by 2 variables: MVT (81%) and PPO (6%).

CONCLUSIONS

It is likely that muscle size and strength, as opposed to neural factors, contribute meaningfully to W'. These data can be used to establish training methods to enhance W' to improve cycling performance in well-trained athletes.

Using Field Based Data to Model Sprint Track Cycling Performance

Cycling performance models are used to study rider and sport characteristics to better understand performance determinants and optimise competition outcomes. Performance requirements cover the demands of competition a cyclist may encounter, whilst rider attributes are physical, technical and psychological characteristics contributing to performance. Several current models of endurance-cycling enhance understanding of performance in road cycling and track endurance, relying on a supply and demand perspective. However, they have yet to be developed for sprint-cycling, with current athlete preparation, instead relying on measures of peak-power, speed and strength to assess performance and guide training. Peak-power models do not adequately explain the demands of actual competition in events over 15-60 s, let alone, in World-Championship sprint cycling events comprising several rounds to medal finals. Whilst there are no descriptive studies of track-sprint cycling events, we present data from physiological interventions using track cycling and repeated sprint exercise research in multiple sports, to elucidate the demands of performance requiring several maximal sprints over a competition. This review will show physiological and power meter data, illustrating the role of all energy pathways in sprint performance. This understanding highlights the need to focus on the capacity required for a given race and over an event, and therefore the recovery needed for each subsequent race, within and between races, and how optimal pacing can be used to enhance performance. We propose a shift in sprint-cyclist preparation away from training just for peak power, to a more comprehensive model of the actual event demands.

Sprint Kayaking Performance Enhancement by Isometric Strength Training Inclusion: A Randomized Controlled Trial

Performing isometric strength training (IST) can enhance various sports performance. This study compared the effects of including IST on sprint kayaking performance as compared to traditional strength training. Twenty sprint kayaking athletes (age 22 ± 4 year, stature 1.71 ± 0.09 m, body mass 72.0 ± 11.4 kg) performed a 200-m kayak ergometer time trial (200mTT), isometric squat (IsoSqT), isometric bench press (IsoPress) and isometric prone bench pull (IsoPull) during the pre- and post-tests. Athletes were randomly assigned to either traditional strength training (TRAD) or IST group. Both groups performed a similar strength training program twice a week for six weeks. However, half the volume for squat, bench press and prone bench pull were replaced by IsoSqT, IsoPress and IsoPull, respectively, for the IST group. IsoSqT was performed at 90° knee angle, while IsoPress and IsoPull were performed at 90° and 120° elbow angles, respectively. Each isometric contraction was performed with maximum intensity and sustained for three seconds. A significant main time effect was observed for 200mTT (p < 0.001, ƞ²_p = 0.68) and all isometric strength measures (p = 0.001–0.032, ƞ²_p = 0.24–0.76) except rate of force development at 0–90 ms (RFD90) obtained from IsoSqT120 and IsoPress90. A group main effect was observed in RFD90 obtained from IsoSqT120 and IsoPull120 (p = 0.003–0.004, ƞ²_p = 0.37–0.39). Time x Group interaction was observed for 200mTT (p = 0.027, ƞ²_p = 0.68), peak force obtained from IsoSqT90, IsoPress90, and IsoPull120 (p = 0.004–0.006, ƞ²_p = 0.36–0.38) and RFD90 obtained from IsoSqT120 and IsoPull120 (p = 0.012–0.015, ƞ²_p = 0.28–0.30). Inclusion of IST resulted in greater improvement for sprint kayaking and strength performances then TRAD alone.

Functional relevance of resistance training-induced neuroplasticity in health and disease

Repetitive, monotonic, and effortful voluntary muscle contractions performed for just a few weeks, i.e., resistance training, can substantially increase maximal voluntary force in the practiced task and can also increase gross motor performance. The increase in motor performance is often accompanied by neuroplastic adaptations in the central nervous system. While historical data assigned functional relevance to such adaptations induced by resistance training, this claim has not yet been systematically and critically examined in the context of motor performance across the lifespan in health and disease. A review of muscle activation, brain and peripheral nerve stimulation, and imaging data revealed that increases in motor performance and neuroplasticity tend to be uncoupled, making a mechanistic link between neuroplasticity and motor performance inconclusive. We recommend new approaches, including causal mediation analytical and hypothesis-driven models to substantiate the functional relevance of resistance training-induced neuroplasticity in the improvements of gross motor function across the lifespan in health and disease.