Physiological and anthropometric characteristics of top-level youth cross-country cyclists

The effect of training distribution, duration, and volume on VO2max and performance in trained cyclists: A systematic review, multilevel meta-analysis, and multivariate meta-regression

OBJECTIVE

This study aimed to systematically investigate whether polarized or non-polarized training leads to greater physiological and performance adaptations in cyclists.

DESIGN

A systematic review and meta-analysis were conducted, focusing on interventions categorized as polarized, non-polarized, or unclear. Inclusion criteria required participants to be at least recreationally trained cyclists (VO2max ≥ 59 ml/kg/min) and interventions lasting > 4 weeks.

METHODS

A multi-level random-effects meta-analysis using restricted maximum likelihood estimation was performed. A multivariate meta-regression assessed associations between training volume, VO2max, and time-trial performance.

RESULTS

Forty-one studies, comprising 81 training groups and 797 participants, were included. Training significantly improved VO2max across all groups (g = 0.42, 95 % confidence interval = 0.31-0.53, P ≤ 0.001) and time-trial performance (g = 0.39, 95 % confidence interval = 0.25-0.53, P ≤ 0.001), with no significant differences between training modalities (P > 0.05). Longer intervention durations positively influenced VO2max (g = 0.03, 95 % confidence interval = 0.02-0.05, P < 0.001) and time-trial performance (g = 0.04, 95 % confidence interval = 0.03-0.06, P < 0.001). No associations were found between weekly or total training volume and changes in VO2max or time-trial performance.

CONCLUSIONS

Polarized and non-polarized training modalities yield comparable improvements in VO2max and time-trial performance in trained cyclists. Beyond achieving a necessary training volume, further increases do not appear to enhance performance. These findings encourage athletes and coaches to prioritize effective training distribution rather than fixating on total volume or a specific model.

Predicting Future Athletic Performance in Young Female Road Cyclists Based on Aerobic Fitness and Hematological Variables

PURPOSE

This study aimed to determine whether the initial levels of aerobic fitness and hematological variables in young female road cyclists are related to their athletic performance development during their careers.

METHODS

Results of graded exercise tests on a cycle ergometer and total hemoglobin mass (tHb-mass) measurements were analyzed in 34 female road cyclists (age 18.6 [1.9] y). Among them, 2 groups were distinguished based on their competitive performance (Union Cycliste Internationale world ranking) over the following 8 years. Areas under the curve in receiver-operating-characteristic curves were calculated as indicators of elite-performance prediction.

RESULTS

Initial graded exercise test variables (peak power, peak oxygen uptake, and power at 4 mmol/L blood lactate) were not significantly different in elite (n = 13) versus nonelite (n = 21) riders. In contrast, elite riders had higher tHb-mass expressed either in absolute measures (664 [75] vs 596 [59] g, P = .006) or normalized to body mass (11.2 [0.8] vs 10.3 [0.7] g/kg, P = .001) and fat-free mass (14.4 [0.9] vs 13.1 [0.9] g/kg, P < .001). Absolute and relative erythrocyte volumes were significantly higher in elite subjects (P ranged from < .001 to .006). Of all the variables analyzed, the relative tHb-mass had the highest predictive ability to reach the elite level (area under the curve ranged from .82 to .85).

CONCLUSION

Measurement of tHb-mass can be a helpful tool in talent detection to identify young female road cyclists with the potential to reach the elite level in the future.

Physiological Characteristics of Competitive Male Junior Cyclists Transitioning to the Under-23 Level: A Retrospective Comparative Study

PURPOSE

The purpose of the current investigation was to retrospectively assess possible differences in physiological performance characteristics between junior cyclists signing a contract with an under-23 (U23) development team versus those failing to sign such a contract.

METHODS

Twenty-five male junior cyclists (age: 18.1 [0.7] y, stature: 181.9 [6.0] cm, body mass: 69.1 [7.9] kg, peak oxygen uptake: 71.3 [6.2] mL·min-1·kg-1) were assigned to this investigation. Between September and October of the last year in the junior category, each cyclist performed a ramp incremental exercise test to determine certain physiological performance characteristics. Subsequently, participants were divided in 2 groups: (1) those signing a contract with a U23 development team (JUNIORU23) and (2) those failing to sign such a contract (JUNIORNON-U23). Unpaired t tests were used to assess possible between-groups differences in physiological performance characteristics. The level of statistical significance was set at P < .05 two tailed.

RESULTS

No significant between-groups differences in submaximal (ie, gas exchange threshold, respiratory compensation point) and maximal physiological performance characteristics (ie, peak work rate, peak oxygen uptake) expressed in absolute values (ie, L·min-1, W) were observed (P > .05). However, significant between-groups differences were observed when physiological performance characteristics were expressed relative to the cyclists' body weights (P < .05).

CONCLUSIONS

The current investigation showed that junior cyclists stepping up to a U23 development team might be retrospectively differentiated from junior cyclists not stepping up based on certain physiological performance characteristics, which might inform practitioners and/or federations working with young cyclists during the long-term athletic development process.

Alterations in aerobic fitness and muscle deoxygenation during ramp incremental exercise in trained youth cyclists: a ~3-year longitudinal study

Alterations of aerobic fitness and muscle deoxygenation during a ramp incremental exercise test (GXT) were assessed on two occasions within a time-frame of 2.9 ± 0.1y in competitive youth cyclists. Nine cyclists (age, 14.5 ± 1.1y; peak oxygen uptake (V˙O_2peak), 62.6 ± 4.2 mL.min^-1.kg^-1) participated in this investigation. V˙O_2peak, the gas exchange threshold (GET) and the respiratory compensation point (RCP), as well as the muscle deoxygenation response pattern were determined during a GXT using open circuit spirometry and near-infrared spectroscopy, respectively. T-tests and Pearson's correlations were used to assess effects of time on the dependent variables and relationships between changes of parameter estimates of aerobic fitness and the muscle deoxygenation response, respectively. Workrate and metabolic rate at GET (33 ± 20 and 42 ± 23%) and RCP (36 ± 20 and 40 ± 22%), and V˙O_2peak (30 ± 18%) significantly increased throughout the study (P < 0.05). The muscle deoxygenation response showed a significant rightward shift from occasion one to two (P < 0.05). Alterations in the workrate/metabolic rate at RCP, and V˙O_2peak, were correlated with alterations of the muscle deoxygenation response (R = 0.71-0.89, P < 0.05). Together, this is thought to indicate a superior muscle perfusion within the tissue of interrogation at the same metabolic rate on occasion two vs. one, which partially contributed to the improved aerobic fitness in the cyclists herein.

Race Performance Prediction from the Physiological Profile in National Level Youth Cross-Country Cyclists

Cross-country mountain biking is an Olympic sport discipline with high popularity among elite and amateur cyclists. However, there is a scarcity of data regarding the key determinants of performance, particularly in young cross-country cyclists. The aim of this study was to examine the physiological profile of youth national-level cross-country cyclists and to determine those variables that were able to best predict the performance in an official race. Ten youth cross-country cyclists of a national team underwent a complete evaluation that included anthropometric assessments, laboratory tests to evaluate the wattage at blood lactate thresholds and at maximal oxygen uptake (PO_VO2max), and field tests to make an in-depth power profile of the athletes. The data obtained in the above-mentioned tests was analysed along with total and partial race times during a competition belonging to the Union Cycliste Internationale (UCI) calendar. In the present study, large and statistically significant correlations (r = -0.67 to -0.95, p ≤ 0.05) were found between maximal and submaximal indices of aerobic fitness and cycling performance, especially when they were normalised to body mass. A multiple regression analysis demonstrated that the wattage at 2 mmol/L, 4 mmol/L and PO_VO2max were able to explain 82% of the variance in total race time. In summary, the results of this study support the use of maximal and submaximal indices of aerobic power as predictors of performance in youth cross-country cyclists.

Aerobic and Anaerobic Power Distribution During Cross-Country Mountain Bike Racing

PURPOSE

To determine aerobic and anaerobic demands of mountain bike cross-country racing.

METHODS

Twelve elite cyclists (7 males; V˙O2max = 73.8 [2.6] mL·min-1·kg-1, maximal aerobic power [MAP] = 370 [26] W, 5.7 [0.4] W·kg-1, and 5 females; V˙O2max = 67.3 [2.9] mL·min-1·kg-1, MAP = 261 [17] W, 5.0 [0.1] W·kg-1) participated over 4 seasons at several (119) international and national races and performed laboratory tests regularly to assess their aerobic and anaerobic performance. Power output, heart rate, and cadence were recorded throughout the races.

RESULTS

The mean race time was 79 (12) minutes performed at a mean power output of 3.8 (0.4) W·kg-1; 70% (7%) MAP (3.9 [0.4] W·kg-1 and 3.6 [0.4] W·kg-1 for males and females, respectively) with a cadence of 64 (5) rev·min-1 (including nonpedaling periods). Time spent in intensity zones 1 to 4 (below MAP) were 28% (4%), 18% (8%), 12% (2%), and 13% (3%), respectively; 30% (9%) was spent in zone 5 (above MAP). The number of efforts above MAP was 334 (84), which had a mean duration of 4.3 (1.1) seconds, separated by 10.9 (3) seconds with a mean power output of 7.3 (0.6) W·kg-1 (135% [9%] MAP).

CONCLUSIONS

These findings highlight the importance of the anaerobic energy system and the interaction between anaerobic and aerobic energy systems. Therefore, the ability to perform numerous efforts above MAP and a high aerobic capacity are essential to be competitive in mountain bike cross-country.

What About the Girls? Exploring the Gender Data Gap in Talent Development

Although there is an extensive literature about talent development, the lack of data pertaining to females is problematic. Indeed, the gender data gap can be seen in practically all domains including sport and exercise medicine. Evidence-based practice is the systematic reviewing of the best evidence in order to make informed choices about practice. Unfortunately, it may be that the data collected in sport is typically about male experiences, and not female; a rather unfortunate omission given that approximately half of the population is made up of women. When female athletes are underrepresented in research there are issues when making inferences about data collected in male dominated research domains to inform practice and policy for female athletes. In parallel, female sport participation is continually increasing worldwide. Recognizing the importance of evidence-based practice in driving policy and practice, and reflecting the gender data gap that is a consistent feature of (almost) all other domains, we were interested in examining whether a gender data gap exists in talent development research. The results suggest that a gender data gap exists in talent development research across all topics. Youth athlete development pathways may be failing to recognize the development requirements of females, particularly where female sports may be borrowing systems that are perceived to work for their male counterparts. In order to ensure robust evidence based practice in female youth sport there is a need to increase the visibility of female athletes in talent development literature.