REF-112 · Wegmann et al., 2012 · Sports Medicine, Vol. · Paper

Pre-cooling and sports performance: a meta-analytical review

A-fairly strong evidenceMeasured on a mixed groupWritten before October 2026, being re-checked

Wegmann et al. located 27 randomized controlled trials on pre-cooling and performance: 18 in hot (> 26 °C) and 8 in moderate conditions; cooling by water application (12 trials), cooling vest (6), cooled room (4), cooling packs (3) and cold drinks (2); tests were short sprints (2), intermittent sprints (6), time trials (10), open-end tests (7) and graded exercise tests (2).

Pre-cooling helped much more in the heat (+6.6%, g = 0.62) than in moderate temperatures (+1.4%, g = 0.004), helped endurance-type tests most and barely affected short sprints. Cold drinks, cooling packs and a cooled room gave the largest effects; vests and water application were small. Fitter subjects (VO2max > 65) benefited more than medium-fit ones.

In the four studies of endurance-trained athletes under time-trial conditions — the most race-relevant subset — the average effect was +3.7% (g = 0.48).

Key Results

Condition / methodPerformance changeEffect size (g)
Hot environment (> 26 °C)+6.6%0.62
Moderate environment+1.4%0.004
Open-end (time-to-exhaustion) tests+8.6%0.52
Graded exercise tests+6.0%0.44
Time trials+4.2%0.44
Intermittent sprints+3.3%0.43
Short high-intensity sprints−0.5%0.03
Cold drinks+15.0%1.68
Cooling packs+5.6%0.70
Cooled room+10.7%0.49
Cooling vest+4.8%0.31
Water application (spraying)+1.2%0.21
VO2max > 65 mL/kg/min+7.7%0.65
VO2max 55-65 mL/kg/min+3.8%0.27
Endurance-trained athletes, time trial (4 studies)+3.7%0.48
Only 2 trials used cold drinks, so the +15.0% figure rests on a very small base.

Practical Application

Across 27 RCTs, pre-cooling improved performance by about +6.6% in the heat (g = 0.62) but only +1.4% in moderate temperatures; for endurance-trained athletes in time-trial conditions — the race-relevant case — the average gain was +3.7% (g = 0.48), and short sprints were unaffected (−0.5%).
Method ranking by pooled effect: cold drinks (+15.0%, but only 2 trials), cooled room (+10.7%), cooling packs (+5.6%), cooling vest (+4.8%), water spraying (+1.2%); the authors name cold drinks, cooling packs and cooling vests as best-practice methods on feasibility grounds.
Fitter athletes gained more (VO2max > 65: +7.7% vs 55-65: +3.8%), so a well-trained athlete racing long in the heat is exactly the case where pre-cooling pays.
Do not bother pre-cooling for a cool-weather race or a sprint event.

Limitations

27 small RCTs; some methods rest on 2-4 trials; effects are percentage changes weighted by subject numbers, not a formal random-effects meta-analysis; mostly laboratory tests.
How this entry was checked and changed
Why this level

regraded 2026-09-27 from B+: meta-analysis of 27 small RCTs across heterogeneous protocols

Content correction 2026-09-27
Method table and the VO2max subgroup figures were already correct. Added from the abstract: hot vs moderate (+6.6% vs +1.4%), effects by test type, the trial counts per method and test, and the most race-relevant number — +3.7% (g = 0.48) in endurance-trained athletes under time-trial conditions — which is now the lead.
Lead "Race day priority: cold drinks (best effect!) + ice vest" -> qualified: cold drinks rest on 2 trials; best-practice methods per the authors are cold drinks, cooling packs and vests.
Level B+ -> A- (meta-analytical review of 27 RCTs).