Accelerated Muscle Recovery in Baseball Pitchers Using Phase Change Material Cooling

The purpose of this study was to document recovery after a pitching performance and determine whether prolonged postgame phase change material (PCM) cooling of the shoulder and forearm accelerates recovery.

Strength, soreness, and serum creatine kinase (CK) activity were assessed before and on the 2 d after pitching performances in 16 college pitchers. Pitchers were randomized to receive either postgame PCM cooling packs on the shoulder and forearm or no cooling (control). PCM packs were applied inside compression shirts and delivered cooling at a constant temperature of 15°C for 3 h. Strength was assessed for shoulder internal rotation (IR), external rotation (ER), empty can (EC) test, and grip.

Total pitch count was 60 ± 16 for 23 PCM cooling games and 62 ± 17 for 24 control games (P = 0.679). On the days after pitching, IR strength (P = 0.006) and grip strength (P = 0.036) were higher in the PCM cooling group versus control. One day after pitching, IR strength was 95% ± 14% of baseline with PCM cooling versus 83% ± 13% for control (P = 0.008, effect size d = 0.91) and 107% ± 9% versus 95% ± 10% for grip strength (P = 0.022, effect size d = 1.29). There was a trend for greater ER strength with PCM cooling (P = 0.091, effect size d = 0.51). The EC strength was not impaired after pitching (P = 0.147) and was therefore unaffected by PCM cooling (P = 0.168). Elevations in soreness and CK were not different between treatments (treatment-time CK P = 0.139, shoulder soreness P = 0.885, forearm soreness P = 0.206).

This is one of the first studies to document impairments in muscle function on the days after baseball pitching, and the first study showing a novel cryotherapy intervention that accelerates recovery of muscle function in baseball pitchers after a game.