The effects of a single whole body cryotherapy exposure on physiological, performance and perceptual responses of professional academy soccer players following repeated sprint exercise

In professional youth soccer players, the physiological, performance and perceptual effects of a single whole body cryotherapy (WBC) session performed shortly after repeated sprint exercise were investigated. In a randomized, counter-balanced and crossover design, 14 habituated English Premier League academy soccer players performed 15 x 30 m sprints (each followed by a 10 m forced deceleration) on two occasions. Within 20 min of exercise cessation, players entered a WBC chamber (Cryo: 30 s at -60[degrees]C, 120 s at -135[degrees]C) or remained seated (Con) indoors in temperate conditions (~25[degrees]C). Blood and saliva samples, peak power output (countermovement jump) and perceptual indices of recovery and soreness were assessed pre-exercise and immediately, 2 h and 24 h post-exercise. When compared to Con, a greater testosterone response was observed at 2 h (+32.5 +/- 32.3 pg[BULLET OPERATOR]ml-1, +21%) and 24 h (+50.4 +/- 48.9 pg[BULLET OPERATOR]ml-1, +28%) post-exercise (both P=0.002) in Cryo (trial x treatment interaction: P=0.001). No between trial differences were observed for other salivary (cortisol and testosterone/cortisol ratio), blood (lactate and Creatine Kinase), performance (peak power output) or perceptual (recovery or soreness) markers (all trial x treatment interactions: P>0.05); all of which were influenced by exercise (time effects: all P<0.05). A single session of WBC performed within 20 min of repeated sprint exercise elevated testosterone concentrations for 24 h but did not affect any other performance, physiological or perceptual measurements taken. While unclear, WBC may be efficacious for professional soccer players during congested fixture periods.