Influence of Cold Water Immersion on Recovery of Elite Triathletes in the Ironman World Championships

Date of Completion

January 2012


Health Sciences, Recreation




Cold water immersion (CWI) has many purposes in athletics, but has been widely used for the purpose of enhancing recovery. While the Ironman triathlon is one of the longest and most stressful endurance events, the application of CWI immersion has never been examined after an Ironman triathlon. PURPOSE: To determine the influence of CWI immediately following an Ironman triathlon on markers of muscle damage, muscle soreness and markers of inflammation. METHODS: Thirty three (22 male, 11 female), competitive, well-trained Ironman athletes participating in the Kona Ironman World Championships participated (Mean±SD: age= 40±11y; height=174.5±9.1cm; weight=70±11.8kg; percent body fat=11.4±4.1%). Upon completion of the race, half of the participants were randomly assigned to CWI in 10°C water for 10 minutes, while the control group sat passively. Data collection occurred prior to, immediately post, 16 hours and 40 hours following the race. A linear mixed model ANOVA with Bonferroni corrections were performed to examine differences between groups across time for delayed onset muscle soreness, hydration indices, myoglobin, creatine kinase (CK), cortisol, testosterone, IL-6 and percent BML (%BML). Pearson's bivariate correlations were used for comparisons with finishing time. Alpha level was set a priori at 0.05. RESULTS: Average finish time (h:min) was 11:03±1:25h (males:10:34±1:08h, females: 12:00±1:30h). Significant differences occurred for post-race BML (-1.7±0.9kg) vs. 16hrs, and 40hrs BML (0.9±1.4, -0.1±1.2kg, respectively; p<0.001). No significant correlation occurred between BML and finishing time (r=0.216, p=0.242). No significant group by time interactions occurred. Significant time effects occurred with all blood measures. Myoglobin and CK were still significantly elevated compared to pre-race values at 40hrs post-race. Cortisol returned to pre-race values by 16hrs post race and IL-6 returned to baseline levels by 40hrs post-race. ^ CONCLUSIONS: The current data found no difference between a CWI recovery strategy and passive recovery in an elite Ironman triathlete population. Specifically, these results are reflective of DOMS. CK, myoglobin, cortisol, and IL-6. Therefore, a single bout of CWI immediately following the race was not sufficient to alter the stress response following the race (up to 40 hours). It is also unknown if the CWI treatment had any effect on recovery outside of 40 hours after the race. Therefore, additional effects of CWI following an Ironman may not have been elucidated. ^