Is skin temperature associated with training load during preparatory period of a professional volleyball team?

The current study investigated if skin temperature (Tsk) measurement through infrared thermography could reflect the accumulation of training load during the preparatory period of a professional volleyball team. Sixteen athletes (20.1 ± 3.1 years, 88.1 ± 6.1 kg, 193 ± 0.1 cm e 13.3 ± 2.3 % body fat) were assessed over two weeks of the preparatory period (5 training days in each week) for the second division of the Brazilian Men's Volleyball Super League. After one week of familiarization with the study procedures, Tsk was measured in eight regions (anterior and posterior areas of arm, shoulder, thigh, and leg) on the first and last training days of each week, along with perceived recovery status (PRS) were measured on the first and last training days of each week. Training load for each session and total weekly training load (TWTL) were calculated using the session rating of perceived exertion (SRPE) method. Three days in the first week and four days in the second week had higher training loads (χ² = 89.1, p < 0.001), as indicated by a significant reduction in recovery perception at the end of each week (F = 52.3, p < 0.001). Among the eight regions examined, five showed a decrease in Tsk after two rest days (weekend), while two regions exhibited an increase in Tsk at the end of the following training week (p < 0.05). Out of 44 associations examined between Tsk, PRS, and TWTL, only the associations between delta PRS and delta mean Tsk of the anterior and posterior leg were significant (β = -0.20, p < 0.045 for both). In conclusion, the data suggest that Tsk may be altered during the pre-competitive period of professional volleyball players; however, it does not appear to be associated with PRS and training load as assessed by the SRPE method.