# Thermal imaging responses of lower-limb muscles following anaerobic testing in male soccer players: A time-series approach

## TL;DR

This study uses thermal imaging to show how soccer players' leg muscles heat up after high-intensity exercise and how body fat affects these changes.

## Contribution

The study introduces a time-series approach to analyze thermal responses in soccer players after anaerobic testing, highlighting the role of body fat as a moderator.

## Key findings

- Right quadriceps skin temperature significantly increased 12 minutes after the Wingate test.
- Body fat percentage modulates thermal responses in quadriceps and hamstrings.
- Lower body fat is associated with greater increases in muscle skin temperature after exercise.

## Abstract

Exercise-induced thermoregulatory responses may vary by sport, yet limited evidence exists on how soccer players respond to high-intensity anaerobic testing. This study aimed to evaluate the acute changes in lower extremity muscle thermal skin temperature(Tsk) in amateur male soccer players following the Wingate anaerobic test and to determine the potential effects of moderators (dominant leg, smoking status, body height, and body fat percentage) on these responses. A total of 26 amateur male soccer players participated in this study, which employed a repeated-measures cross-sectional design. Infrared thermography(IRT) was used to record Tsk data from six anatomical locations(bilateral quadriceps, hamstrings, and gastrocnemii) at five different time points(baseline, 15 seconds, 4, 8, and 12 minutes) following a Wingate anaerobic test. Data were analyzed using the Frequentist and Bayesian repeated-measures ANOVA. The results showed a statistically significant effect of time in the right quadriceps region(p = 0.01,ηp² = 0.15,BFincl = 19.51). Post-hoc analysis indicated a significant increase in the Tsk of the right quadriceps at 12 minutes following the test, compared to baseline measurements(p = 0.02; BF10 = 17.931). Moderator analyses revealed that body fat percentage influenced Tsk responses, particularly in the quadriceps and hamstring regions(p = 0.01–0.03,ηp² = 0.25,BFincl = 3.100–3.958). Players with lower body fat showed significantly greater increases in quadriceps and hamstring muscle TSK than players with higher body fat (p < 0.05). In conclusion, this study highlights a notable rise in dominant quadriceps skin temperature following high-intensity anaerobic exercise in amateur male soccer players. Body fat percentage appears to modulate these thermal responses, underlining its importance when interpreting IRT results in sports settings. These findings may have practical implications for performance monitoring and thermal recovery strategies in soccer players.