Author(s): KRAUTH-IBARZ, T., BEAVEN, M., VARESCO, G., GOLDBERG, J., PRADELLA, A., JAFFAL, M., CORREA, J., BIEUZEN, F., CHURCHWARD-VENNE, T.A., Institution: MCGILL UNIVERSITY, Country: CANADA, Abstract-ID: 2385

INTRODUCTION:
Cold-water immersion (CWI) is a recovery method that may alleviate fatigue and restore performance. However, repeated CWI applied immediately after resistance training can interfere with long-term adaptive increases in muscle size and strength. Homeostatic perturbations to muscle mostly occur during exercise and in the early phase of recovery. Timing of CWI may be important for balancing adaptation and recovery. However, limited information exists on how delaying CWI influences same-day recovery of strength, power, and muscular endurance. This study investigated the effects of immediate vs. delayed CWI after acute resistance exercise on same-day performance recovery in athletes.
METHODS:
In a randomized crossover study, 12 tier 3 athletes (6 F and 6 M; mean age: 24 (SD: 5) y) completed 3 visits. Each visit included a standardized meal and a bout of resistance exercise consisting of 8 sets x 10 repetitions at 65% 1RM. Performance testing was performed pre, immediately post, and 5 h post-exercise. Tests included 5 countermovement jumps (CMJ), 10 s knee-extensor maximum voluntary isometric contraction (MVIC), 5 knee-extensor isokinetic contractions at 60/180/240 deg/s, and 1 set of leg press performed as repetitions to failure (RTF). Post-exercise, athletes completed 1) immediate thermoneutral water immersion (THERM; 35 deg C), 2) immediate CWI (CWI0; 10 deg C), or 3) 3 h delayed CWI (CWI3; 10 deg C) to mid-sternum for 10 min. Data were analysed using linear mixed-effects regression; RTF was analysed using Poisson mixed-effects regression.
RESULTS:
Model-adjusted means (SE) showed no difference between immersion conditions at 5 h post-exercise for MVIC (THERM: 173.1 (4.7); CWI0: 169.9 (4.5); CWI3: 165.5 (4.5) Nm; all p >.05), or CMJ height. At 5 h, isokinetic peak torque was lower in CWI3 compared with THERM at 60 deg/s (diff = -16.7 Nm, 95% CI [-1.8, -31.7], p = .026), 180 deg/s (diff = -9.8 Nm, 95% CI [-1.1, -18.4], p = .025), and 240 deg/s (diff = -6.7 Nm, 95% CI [-0.3, -13.1], p = .040). At 5 h, isokinetic peak torque at 180 deg/s was lower in CWI3 than in CWI0 (diff = -10.1 Nm, 95% CI [-1.0, -19.2], p = .027). At 5 h post-exercise, RTF were greater in CWI3 vs. THERM (21 (2) vs. 17 (1); p = .043), with no difference between CWI0 (21 (2); p = .131) and THERM.
CONCLUSION:
Delayed CWI following acute resistance exercise impaired same-day recovery of isokinetic torque but improved muscular endurance vs. thermoneutral water immersion in athletes. These findings indicate CWI timing after resistance exercise differentially modulates velocity-specific torque production and muscular endurance. These divergent effects suggest delayed CWI affects performance recovery in a task-specific manner with implications for training and recovery prescription.