Table 2.
Study characteristics
| Author (year) | Aim | Number of studies | Number of participants | Cooling Interventions | Study context | Type of analysis |
|---|---|---|---|---|---|---|
| Adams 2014 [91] | Evaluate the change in heart rate for every 1% loss in body mass | 20 |
a188 (173 M, 15 F) |
Hydration | Athletic performance | ES + MR |
| Alhadad 2019 [93] | Evaluate heat mitigation strategies to lower core temperature pre, mid and post exercise | 123 |
a1470 (1382 M, 88 F) |
Aerobic fitness, heat acclimation (low and high humidity), fluid ingestion (ad libitum, low and high consumption, hypohydrated, euhydrated), pre-cooling (cold water immersion, cold air exposure, cooling vests, cold fluid ingestion, ice slurry ingestion) | Athletic performance | ES |
| Best 2018 [80] | Meta-analyze the effect of internal and external cooling methods applied before and during exercise on performance | 10 |
a101 (101 M, 0 F) |
Ice slurry ingestion, ice towels, oral rehydration, water dousing, external menthol application, cold fluids with menthol | Athletic performance | ES |
| Bongers 2015 [89] | Evaluate precooling and percooling on exercise performance and thermoregulatory responses | 28 |
a261 (283 M, 8 F) |
Cooling vest, cold water immersion, cold water ingestion, cooling packs, mixed methods | Athletic performance | ES + MR |
| Born 2013 [88] | Summarize evidence concerning compression garments on performance and recovery | b3 |
30 (30 M, 0 F) |
Compression garments | Athletic performance | ES |
| Brearley 2015 [81] | Efficacy of water immersion in firefighting settings to rapidly reduce core temperature | 43 |
642 (517 M, 125 F) |
Limb immersion | Firefighters | QUAL |
| Burdon 2010 [86] | Determine whether ingesting cool beverages lowers core temperature and improves athletic performance | 10 |
86 (86 M, 0 F) |
Cold fluid ingestion | Athletic performance | ES |
| Burdon 2012 [84] | Effect of beverage temperature on drink palatability | 11 |
233 (208 M, 25 F) |
Fluid ingestion | Athletic performance | ES |
| Chalmers 2014 [65] | Investigate the effect of short term heat acclimation on physical performance | 8 |
98 (79 M, 19 F) |
Short term heat acclimation | Athletic performance | QUAL |
| Chan 2015 [73] | Determine the effectiveness of multiple microenvironment cooling systems on physical performance | 32 |
235 (231 M, 4 F) |
Phase change garments, air cooled garments, cold-air cooled garments, liquid cooled garments, hybrid cooling garments, local cooling packs, cooling packs on neck and head | Sport, military, chemical protection, firefighting, and occupational health | ES + MR |
| Choo 2018 [79] | Effect of cold water immersion and ingestion on psychophysiological and athletic performance | 22 |
245 (213 M, 32 F) |
Cold water immersion, ice slurry ingestion | Athletic performance | ES |
| Daanen 2018 [64] | Systematically review and analyze heat acclimation decay and reacclimation | 21 |
449 (428 M, 21 F) |
Heat acclimation (decay) | Athletic performance | MR |
| Douzi 2019 [75] | Evaluate effect of various methods of percooling on aerobic and anaerobic performance | 36 |
a,c379 (356 M, 23 F) |
Neck cooling, air-ventilation, cold fluid ingestion, ice vests, cooling garments | Athletic performance | ES |
| Goodman 2019 [70] | Meta-analyze the effect of active hypohydration on cognitive performance | 10 |
179 (124 M, 55 F) |
Hypohydration | Cognitive performance | ES |
| Goulet 2011 [85] | Effect of exercise induced dehydration on time trial performance | 5 |
39 (32 M, 7 F) |
Exercise induced dehydration | Athletic performance | ES + MR |
| Hefferman 2019 | Systematically review trace mineral element supplementation on athletic performance | e15 |
a377 (328 M, 49 F) |
Sodium supplementation | Athletic performance | QUAL |
| Holland 2017 [67] | Determine effect of fluid ingestion on exercise performance | 9 |
71 (64 M, 7 F) |
Fluid ingestion | Athletic performance | ES + MR |
| Jeffries 2019 [77] | Meta-analyze the effect of menthol use on athletic performance and psychophysiological responses | 11 |
126 (126 M, 0 F) |
Internal and external menthol application | Athletic performance | ES |
| Jones 2012 [66] | Summarize the effectiveness of pre cooling methods | 13 |
119 (108 M, 11 F) |
Cold water immersion, cooling garment, cold water ingestion, ice slurry ingestion, leg cooling | Athletic performance | ES |
| Junge 2016 [95] | The effect of environmental heat stress factors on cycling time trial performance | 14 |
a145 (131 M, 14 F) |
Environmental conditioning | Athletic and occupaltional performance | MR |
| Martin 2019 [94] | Environmental heat stress on cognitive and military task performance | f31 |
a683 (563 M, 120F) |
Environmental heat stress | Cognitive and military task performance | QUAL |
| McCartney 2017 [68] | Fluid intake following dehydration on physical and cognitive performance | 64 |
643 (598 M, 45 F) |
Fluid ingestion | Athletic performance | ES |
| McDermott 2009 [88] | Evaluate the effect of whole-body methods for reducing exercise induced hyperthermia | 7 |
a68 (56 M, 12 F) |
Cold water immersion, wet towels, cold air exposure, skin wetting with fan use, ice packs, | Athletic performance | QUAL |
| McEntire 2013 [83] | Systematically review cooling techniques and practices among firefighters | 27 |
a308 (287 M, 21 F) |
Passive cooling in air, hand and arm immersion, foot immersion, cooling vests, hand cooling, intravenous cooling, fanning, fanning with misting, cooling sock, liquid and air cooled suits, | Firefighters | QUAL |
| Rahimi 2019 [78] | Heat acclimation on athletic performance and psychophysiological responses | 11 |
215 (195 M, 20 F) |
Heat acclimation | Athletic performance | ES |
| Ranalli 2010 [74] | Effect of body cooling on exercise performance | c9 |
a107 (92 M, 15 f) |
Ice vest, cold water immersion, cooling collar | Athletic performance | %Increase |
| Ross 2013 [97] | Evaluate the established pre-cooling literature | 64 |
631 (587 M, 44 F) |
Cold air, cold water immersion, cooling packs, cooling vests, ice towels, cold water ingestion, cold air inhalatiion | Athletic performance | QUAL |
| Ruddock 2017 [72] | Does cooling during exercise decrease physiological strain and improve exercise performance | 15 |
135 (135 M, 0 F) |
Cold fluid, ice slurry, neck cooling collar, hand cooling, | Athletic performance | ES |
| Stearns 2010 [87] | Meta-analyze the effect of protein and carbohydrate ingestion on exercise performance | d1 |
a13 (7 M, 6 F) |
Protein ingestion | Athletic performance | QUAL |
| Tomes 2017 [71] | Effect of wearing protective body armour | 16 |
433 (353 M, 80 F) |
Clothing variety (protective) | Law enforcement personnel wellbeing | QUAL |
| Tyler 2015 [90] | Effect of pre and percooling on exercise performance and capacity in the heat | 38 |
335 (318 M, 17 F) |
Mist and fan, ice vest, neck cooling collar | Athletic performance | ES |
| Tyler 2016 [69] | Effect of heat acclimation on physiological, perceptual and performance variables | 96 |
1056 (980 M, 76 F) |
Heat acclimation | Athletic performance | ES |
| Vandenbogaerde 2011 | Conduct a meta-analysis to determine the effect of carbohydrates on athletic performance | 154 |
1628 (1469 M, 159 F) |
Carbohydrate ingestion | Athletic performance | MR |
| Walker 2016 [96] | Investigate the effect of fighting fires on hydration status | 10 |
225 (214 M, 11 F) |
Hydration | Firefighter hydration | QUAL |
| Wegmann 2012 [92] | Effect of pre cooling on sport performance | 27 |
268 (260 M, 8 F) |
Cooling vest, cold water immersion, skin wetting, cooling packs, cold water ingestion, cold air | Athletic performance | ES |
| Wittbrodt 2018 [98] | Determine the impact of dehydration on cognitive performance | 33 |
463 (396 M, 67 F) |
Hydration | Athletic and occupational cognitive performance | ES + MR |
M Male; F Female; ES Effect size; MR Meta-regression; QUAL Qualitative analysis
a Distribution of male and female participants determined from the original investigations
b Only includes studies examining the effect of core temperature as exercise performance was conducted in temperate conditions
c Includes only the studies examining effect on aerobic performance/ excludes anaerobic performance
d While this review examined and meta-analysed the results of 11 studies, they marked that protein ingestion was only
e Number of studies pertaining to sodium ingestion only
f Number of studies pertaining to the heat only