Chow G.C.C.1, Yam T.T.T.1, Chung J.W.Y.2, Fong S.S.M.1
1University of Hong Kong, School of Public Health, Hong Kong, Hong Kong, 2Education University of Hong Kong, Department of Health and Physical Education, Hong Kong, Hong Kong
Background: Ice-water immersion (IWI) is a post-exercise recovery strategy that has been widely studied and is commonly used by rugby players. However, IWI is not always well tolerated. Theoretically, room-temperature water immersion (RWI) has a similar recovery effect to that of IWI, which means that RWI might provide an acceptable alternative to IWI for rugby players. Postural control and joint proprioception are two important parameters that determine the performance of rugby players. Therefore, we measured both standing balance performance and knee joint proprioception of the amateur rugby players in this study.
Purpose: This study compared the effects of post-exercise IWI, RWI, and no water immersion on the standing balance performance and knee joint proprioception of amateur rugby players.
Methods: It was a single-blinded, three-armed randomized controlled clinical trial. Fifty-three eligible amateur rugby players were randomly assigned to the IWI group (water temperature = 5.3°C; mean age ± standard deviation = 22.9 ± 2.4 years; 7 males and 6 females), RWI group (water temperature = 25.0°C; mean age ± standard deviation = 21.8 ± 3.4 years; 10 males and 8 females), or the no immersion control group (room temperature = 25.0°C and relative humidity = 75%; mean age ± standard deviation = 20.7 ± 2.4 years; 12 males and 10 females). The participants in each group underwent the same fatigue protocol (sprinting on a motorized treadmill) followed by their allocated recovery intervention, which lasted for 1 minute. Measurements were taken before and after the fatigue-recovery intervention by a sports scientist and two trained assistants. The primary outcomes were the sensory organization test (SOT) composite equilibrium score and the 6 condition-specific equilibrium scores, which were measured using a computerized dynamic posturography machine. The secondary outcome was the knee joint repositioning error which was measured using the knee joint angle repositioning test.
Results: Two-way repeated measures analysis of variance results revealed that there were no significant within- and between-group differences in the SOT composite equilibrium scores or the condition-specific equilibrium scores. However, there was a group-by-time interaction effect on the knee joint repositioning error. Further analysis showed that participants in the RWI group had lower errors over time, but those in the IWI and control groups had increased errors over time.
Conclusion(s): Post-exercise ice-water or room-temperature water immersion did not impair rugby players sensory organization of balance control. However, room-temperature water immersion had a better effect on knee joint proprioception to ice-water immersion and no water immersion.
Implications: This study demonstrated the feasibility of using room-temperature water immersion, a relatively comfortable treatment, in place of ice-water immersion for reducing heat-related fatigue among rugby players.
Funding acknowledgements: No funding was provided for this study.
Topic: Sport & sports injuries
Ethics approval: Human Research Ethics Committee, the University of Hong Kong
All authors, affiliations and abstracts have been published as submitted.
