Post-exercise effects of cold water immersion and contrast water therapy. Part 1. Acute effects of cold water immersion and passive recovery on the physical and haematological parameters in male university rugby players over a 48-hour recovery period

Abstract

However, there are discrepancies in the results regarding the post-exercise effects of CWI over a 48-hour recovery period. Therefore, the objective of this study was to determine the post-exercise effects of CWI and passive recovery (PAR) on the physical and haematological parameters of male university-level rugby players over a 48-hour recovery period. A cross-sectional, pre-posttest experimental study design with convenience sampling was used. Six haematological [blood lactate (BLa-), partial O2 pressure (PO2), blood glucose, sodium (Na+), haematocrit and haemoglobin] and four physical parameters (vertical jump test (VJT) -height, VJT-speed and VJT-power as well as grip strength) were evaluated at baseline, after a 15-minute fitness session, and at 0, 24 and 48 hours post-recovery in 23 male university rugby players. The CWI group sat in a cold water pool (8°C) for 20 minutes whereas the PAR group remained seated in a laboratory. At 0 hours post-CWI, BLa-, Na+ and haemoglobin returned to baseline values whereas VJT-height decreased compared to post-PAR values which improved. From 0 to 24 and/or 48 hours, PO2, VJT-height, plasma glucose, and Na+ significantly increased (p ≤ 0.05) in either and/or both groups. Significant intragroup differences (p ≤ 0.05) were noticed for BLa- and grip strength at 0 and 24 hours. VJT-height, -speed and -power were worse at 0 hours post-CWI compared to PAR. However, CWI was superior over 24 hours post-recovery to improve haemoglobin, haematocrit, Na+ and grip strength. Therefore, in cases where recovery over a longer period is required (48 hours), CWI is superior compared to PAR to restore the body’s physiological parameters and enhance recover