Cryotherapy re-invented: application of phase change material for recovery in elite soccer

Purpose:

This study examined whether donning lower body garments fitted with cooled phase change material (PCM) would enhance recovery after a soccer match.

Methods:

In a randomized, crossover design, eleven elite soccer players from the reserve squad of a team in the 2nd highest league in England wore PCM cooled to 15°C (PCMcold) or left at ambient temperature (PCMamb) for 3 h after a soccer match. To assess recovery, countermovement jump (CMJ) height, maximal isometric voluntary contraction (MIVC), muscle soreness (MS), and the adapted Brief Assessment of Mood Questionnaire (BAM+) were measured before, 12, 36 and 60 h after each match. Pre and post intervention, a belief questionnaire (BFQ) was completed to determine perceived effectiveness of each garment.

Results:

Results are comparisons between the two conditions at each time point post-match. MIVC at 36 h post was greater with PCMcold vs. PCMwarm (P=0.005; ES=1.59; 95% CI=3.9 to 17.1%). MIVC also tended to be higher at 60 h post (P=0.051; ES=0.85; 95% CI= −0.4 to 11.1%). MS was 26.5% lower in PCMcold vs. PCMwarm at 36 h (P=0.02; ES=1.7; 95% CI= −50.4 mm to −16.1 mm) and 24.3% lower at 60 h (P=0.039; ES=1.1; 95% CI= −26.9 mm to −0.874 mm). There were no between condition differences in post-match CMJ height or BAM+ (P>0.05). The BFQ revealed that players felt the PCMcold was more effective than the PCMamb after the intervention (P=0.004).

Conclusions:

PCM cooling garments provide a practical means of delivering prolonged post exercise cooling and thereby accelerating recovery in elite soccer players.