This randomized crossover study investigated the effects of whole-body cryotherapy (WBC) on isokinetic knee performance following running-induced fatigue in physically active healthy male university students. Participants completed two recovery conditions, WBC and passive rest, on separate days following a standardized treadmill fatigue protocol. Knee extension and flexion strength were assessed using an isokinetic dynamometer at angular velocities of 60°/s and 240°/s. In addition, blood pressure, heart rate, oxygen saturation, and perceived fatigue responses were monitored throughout the recovery period. The study aimed to determine whether WBC improves post-exercise recovery and lower-extremity muscle performance compared with passive rest.

This study was designed to investigate the effects of whole-body cryotherapy (WBC) on recovery and isokinetic muscle performance following exercise-induced fatigue in physically active healthy male university students. Exercise-induced fatigue is associated with reduced muscle force production, impaired performance, and increased injury risk. Various recovery strategies have been used to minimize these negative effects, and WBC has gained increasing attention in sports medicine because of its potential physiological and neuromuscular recovery benefits.

The study used a randomized within-subject crossover design in which participants completed two recovery conditions, WBC and passive rest, on separate days following a standardized treadmill-based fatigue protocol. During the WBC condition, participants were exposed to a two-stage cryogenic chamber consisting of an adaptation chamber at -30°C followed by a main chamber at -85°C. Passive rest sessions were performed under the same laboratory conditions without cryotherapy exposure.

Primary outcome measures included isokinetic knee extension and flexion performance assessed at angular velocities of 60°/s and 240°/s using an isokinetic dynamometer. Peak torque and body mass-normalized peak torque values were analyzed for both dominant and non-dominant lower extremities. Secondary outcome measures included systolic and diastolic blood pressure, heart rate, oxygen saturation, and perceived fatigue responses measured throughout the recovery period.

The aim of the study was to determine whether WBC provides superior recovery effects compared with passive rest following running-induced acute fatigue.

Inclusion Criteria:

• Healthy male participants aged 18-30 years with no exercise limitation
• No history of knee or lower-extremity injury requiring physiotherapy or surgical intervention
• No current lower-extremity pain
• No limitation in lower-extremity range of motion
• No chronic disease
• No mental or psychological disorder

Exclusion Criteria:

• Presence of cardiovascular disease
• Presence of respiratory disease
• History of cold allergy
• Presence of a tumor-related disease
• Presence of a viral or bacterial infection
• Diagnosis of Raynaud's disease
• Presence of claustrophobia