Harry P. Cintineo, Marissa L. Bello, Bridget A. McFadden, Alan J. Walker, David J. Sanders, Brittany N. Bozzini, Ryan Curtis, Robert A. Huggins, Douglas J. Casa, Shawn M. Arent
Athlete monitoring is critical for ensuring maximal performance during the season. The competitive stress is often more pronounced as teams enter conference play. Both objective and subjective assessments have been promoted as indicators of performance, readiness, and recovery in athletic populations.
PURPOSE: To analyze the relationship between workload and performance outcomes, as well as corresponding changes in biomarkers and self-report questionnaires over the course of conference play in Division I collegiate female soccer players.
METHODS: Female (n=21; Mage=19.7±1.35 yrs; Mweight=66.0±5.9 kg) collegiate soccer players were monitored throughout a competitive season. Training load (TL) and energy expenditure (Kcal/kg) were measured using the Polar TeamPro system. Athletes participated in a battery of testing every 4 weeks including reaction time (RT) and speed (SP) using computer simulation and full-body sensing technology. Athletes completed questionnaires, including Profile of Mood States (POMS) and Disability in the Physically Active (DPA), on the same day as performance testing. Athletes arrived fasted and euhydrated to blood draws (BD), which were conducted 2 weeks prior to each performance testing session and approximately 18-36 hours after a match. Biomarkers analyzed included catecholamines (E/NE), free cortisol (CORTF), and total cortisol (CORTT). RM MANOVAs and simple contrasts were conducted with significance set at P<.05.
RESULTS: TL and Kcal/kg decreased during conference play compared to the period of non-conference play that preceded it (P<.05). There was a trend for an increase in SP from T1 to T2 (DSP=.067±.03 m/s, P=.062) before stabilizing at T3. There was no significant effect on RT (P=.42). There was a trend for increased POMS Anger (P=.098), primarily due to an increase from T2 to T3 (DAnger=-2.5±1.4; P<.10). There were no other significant POMS or DPA changes. There were significant time main effects for E/NE (P<.001), with a decrease from BD1 to BD2 (DE/NE=-139.3±31.9 pg/mL; P<.001) with no further change from BD2 to BD3 (P=.33). CORTF had a significant linear increase from BD1 to BD3 (DCORTF=.63±.12 mcg/dL; P<.001). CORTT did not significantly change (P=.93).
CONCLUSION: A decrease in TL and Kcal/kg corresponded to an improvement in SP and a decrease in E/NE. However, there was a continued rise in CORTF despite the reduction in workload. This would suggest that workload alone does not fully explain athlete stress or that there may be a residual and lasting influence of preseason and early season workload. This may be enhanced by in-conference competition. The lack of significant changes in subjective measures suggests that these may not be as useful for reporting athlete readiness as has previously been suggested. Instead, the changes in E/NE in the weeks prior to the performance assessments mirrored the changes in speed. There may be predictive utility in these assessments. CORTF also appears to be a more sensitive marker than CORTT.
PRACTICAL APPLICATIONS: While subjective measures of athlete readiness have practical appeal, the utility of their use heavily relies on both sensitivity and athlete honesty. As objective measures, E/NE appeared to have a more consistent association with workload and performance changes. CORTF may also be used to assess accumulating stress.