By Perttu Noponen
Noponen, Perttu 2013. Effects of far infrared warm on recovery in power athletes during a 5- day training period. Master’s Thesis in Science of Sport Coaching and Fitness Testing, Department of Biology of Physical Activity. University of Jyväskylä, 56 pages.
Purpose. Scientific evidences of thermal therapy on performance recovery are limited and also controversial. It has been shown recently by Hausswirth et al. (2011) that far infrared (FIR) therapy accelerates recovery, while it is also documented that temperate water immersion does not improve performance recovery (Pournot et al. 2011). The purpose of the present study was to find more concrete information about the effects of the thermal therapy and especially the FIR warm on the recovery of the athletes.
Methods. The experimental group consisted of ten national level male athletes (22.3 ± 4.5 years) from the power events in track and field, gymnastics and Finnish baseball. The experimental group was its own control group. Starting order of the subjects in the groups was randomized. Training and nutrition were standardized during the 5-day training period. The experimental design consisted of performance tests (isometric strength tests, countermovement jump and Wingate 30 s test), questionnaires and the fasting blood samples (testosterone, cortisol, SHBG, hsCRP and creatinekinase [CK]). In contrast to the control period, during the experimental period the subjects used infrared bag (FIR65º, U2i / Oy You Two Import Ltd, Oulu, Finland, 40 min / 50 ºC) every evening from Monday to Thursday. Statistical analyses included ANOVA and paired samples t-test. Level of significance was set at p<0.05.
Results. Average power in Wingate 30 s test increased significantly (p = 0.015) during the experimental condition, while during the control condition no significant changes were observed. There were no significant differences in the blood variables between the measurement periods. However, there was a significant increase in the blood SHBG level (p = 0.032) between the first and the third day and in the testosterone level (p = 0.023) between the third and the fifth day during the experimental condition. The level of CK was significantly higher in the second day than in the first day (p = 0.023) during the control condition and in the third day than in the first day during the control (p = 0.007) and the experimental conditions (0.030). The relative change in the testosterone/cortisol ratio between the day one and the day five increased significantly more (p = 0.026) during the experimental condition than during the control condition. The sensations in the muscle soreness were milder during the experimental condition when compared to the control condition.
Discussion and conclusions. The present study indicates that FIR warm improves recovery of the anaerobic performance during the 5- day training period. The subjective sensations support the positive effects of the FIR warm on recovery. The changes in the testosterone/cortisol ratio, CK response, and serum testosterone and SHBG levels indicate probability to the improved anabolic state and accelerated recovery due to the FIR warm. However, because there were no significant changes in blood variables between the two conditions, additional studies are needed considering the effects of the FIR warm on them. According to this study FIR warm therapy enhances the recovery after a short 5- day training period when compared to the passive recovery modality.