Cooling during exercise enhances performances, but the cooled body areas matter: A systematic review with meta‐analyses

Abstract

Introduction Hyperthermia during exercise induces central and peripheral fatigue and impairs physical performance. To facilitate heat loss and optimize performance, athletes can hasten body cooling prior (pre‐cooling) or during (per‐cooling) exercise. However, it is unclear whether per‐cooling effect is the same on ‘aerobic’ and ‘anaerobic’ types of exercise (duration <75 and >76 seconds, respectively, according to Gastin [Sports Med 2001;31:725‐741]) and whether the body area that is cooled makes a difference. Methods A literature search led to the identification of 1582 potential studies. Included studies had to include physical exercise with sufficient details on the type, duration, intensity, and provide valid performance measures and a cooling intervention administered during exercise with sufficient details on the type and site of application. Results Forty‐five studies were included. Per‐cooling provides a performance benefit during ‘aerobic’ (standardized mean difference (SMD) of 0.60, P < .001) and ‘anaerobic’ exercises (SMD = 0.27, P < .02). The effects were greater during aerobic compared to anaerobic exercises (P < .01). Internal cooling (cold fluid ingestion such as cold water and ice slurry/menthol beverage) and external cooling (face, neck, and torso) provide the greatest performance benefit for ‘aerobic’ performance with a moderate to large effect (0.46 < SMD < 1.24). For ‘anaerobic’ exercises, wearing a whole‐body cooling garment is the best way to enhance exercise performance (SMD = 0.39, P < .01). Conclusion Per‐cooling improves ‘aerobic’ and ‘anaerobic’ exercise performance with a greater benefit for ‘aerobic’ exercise. The magnitude of the effect depends on the type and site of the cooling application.

Sustainable solutions to mitigate occupational heat strain – an umbrella review of physiological effects and global health perspectives

“…This is likely because the effectiveness of these types of cooling interventions will be environment dependent, as has been previously illustrated [32]. Of all the external cooling strategies, cold water immersion was the most effective cooling intervention, primarily during precooling but during intermittent cooling as well [66,75,79,89]. Cold water immersion is most effective when cold water is used and the entire body is submerged; this practice, however, is entirely implausible for nearly all occupational settings and likely is only realistic within a sporting context.…”

“…The use of cooling packs, cooling collars and wet towels containing ice were other, albeit less effective, cooling options [73,75,89]. This smaller cooling effect, relative to cold water immersion or cooled garments, is likely due to the smaller surface area for cooling of the packs, and the effect appears to be generally uniform regardless of the area of the body applied to (i.e.…”

“…Additionally, in the one review looking at the effect of cooling location on physical performance [75], face cooling was found to be the most important cooling location, followed by the torso, and internal cooling. This effect was likely due to differences in human thermal comfort, as thermal sensation of the face [159] and back [160] have been demonstrated to have the greatest impact on thermal comfort in the heat.…”

Per-Cooling (Using Cooling Systems during Physical Exercise) Enhances Physical and Cognitive Performances in Hot Environments. A Narrative Review

“…To date, there is only one meta-analysis (that we recently published) that synthesizes what is known on the impact of cooling different parts of the body on different kinds of physical performance, and the meta-analysis should be considered a companion work of the present narrative review. In the former meta-analysis, we were able to show that per-cooling improves both 'aerobic' and 'anaerobic' exercise performance with a greater benefit for 'aerobic' exercise and that the magnitude of the effect depends on the type and site of the cooling application [28].…”

Cooling During Exercise May Induce Benefits Linked to Improved Brain Perfusion

“…Furthermore, several studies show that increasing body-cooling during physical exercise (e. g. by using a cooling vest) can prolong its duration [17][18][19][20] and promote thermal comfort [12]. Recent meta-analyses and reviews concluded that cooling vests appeared to be the most effective method in performance improvement [17,18,21,22]. Therefore, it was established that wearing a cooling vest is an efficient cooling technique, especially when it covers a relatively large surface of the body [17].…”