TY - JOUR
T1 - Heat acclimation improves heat exercise tolerance and heat dissipation in individuals with extensive skin grafts
AU - Schlader, Zachary J.
AU - Ganio, Matthew S.
AU - Pearson, James
AU - Lucas, Rebekah A.I.
AU - Gagnon, Daniel
AU - Rivas, Eric
AU - Kowalske, Karen J.
AU - Crandall, Craig G.
N1 - Publisher Copyright:
Copyright © 2015 the American Physiological Society.
PY - 2015/7/1
Y1 - 2015/7/1
N2 - Burn survivors with extensive skin grafts have impaired heat dissipation and thus heat tolerance. This study tested the hypothesis that heat acclimation (HA) improves these factors in this population. Thirty-four burn survivors were stratified into highly [>40% body surface area (BSA) grafted, n = 15] and moderately (17-40% BSA grafted, n = 19) grafted groups. Nine healthy nonburned subjects served as controls. Subjects underwent 7 days of HA involving 90 min of exercise at ∼50% peak oxygen uptake in 40°C, 30% relative humidity. On days 1 and 7, subjects exercised in the heat at a fixed rate of metabolic heat production. Pre-HA, all controls and 18/19 subjects in the 17-40% group completed 90 min of exercise. Conversely, heat exercise tolerance was lower (P < 0.01) in the >40% group, with 7/15 subjects not completing 90 min of exercise. Post-HA, heat exercise tolerance was similar between groups (P = 0.39) as all subjects, except one, completed 90 min of exercise. Pre-HA, the magnitude of the increase in internal temperature during exercise occurred sequentially (P ≤ 0.03) according to BSA grafted (>40%: 1.6 ± 0.5°C; 17-40%: 1.2 ± 0.3°C; control: 0.9 ± 0.2°C). HA attenuated (P < 0.01) increases in internal temperature in the control (by 0.2 ± 0.3°C), 17-40% (by 0.3 ± 0.3°C), and >40% (by 0.3 ± 0.4°C) groups, the magnitude of which was similar between groups (P = 0.42). These data indicate that HA improves heat tolerance and dissipation in burn survivors with grafted skin, and the magnitude of these improvements are not influenced by the extent of skin grafting.
AB - Burn survivors with extensive skin grafts have impaired heat dissipation and thus heat tolerance. This study tested the hypothesis that heat acclimation (HA) improves these factors in this population. Thirty-four burn survivors were stratified into highly [>40% body surface area (BSA) grafted, n = 15] and moderately (17-40% BSA grafted, n = 19) grafted groups. Nine healthy nonburned subjects served as controls. Subjects underwent 7 days of HA involving 90 min of exercise at ∼50% peak oxygen uptake in 40°C, 30% relative humidity. On days 1 and 7, subjects exercised in the heat at a fixed rate of metabolic heat production. Pre-HA, all controls and 18/19 subjects in the 17-40% group completed 90 min of exercise. Conversely, heat exercise tolerance was lower (P < 0.01) in the >40% group, with 7/15 subjects not completing 90 min of exercise. Post-HA, heat exercise tolerance was similar between groups (P = 0.39) as all subjects, except one, completed 90 min of exercise. Pre-HA, the magnitude of the increase in internal temperature during exercise occurred sequentially (P ≤ 0.03) according to BSA grafted (>40%: 1.6 ± 0.5°C; 17-40%: 1.2 ± 0.3°C; control: 0.9 ± 0.2°C). HA attenuated (P < 0.01) increases in internal temperature in the control (by 0.2 ± 0.3°C), 17-40% (by 0.3 ± 0.3°C), and >40% (by 0.3 ± 0.4°C) groups, the magnitude of which was similar between groups (P = 0.42). These data indicate that HA improves heat tolerance and dissipation in burn survivors with grafted skin, and the magnitude of these improvements are not influenced by the extent of skin grafting.
KW - Burn injury
KW - Heat adaptation
KW - Heat loss
KW - Heat tolerance
KW - Hyperthermia
KW - Skin grafting
UR - http://www.scopus.com/inward/record.url?scp=84937212292&partnerID=8YFLogxK
U2 - 10.1152/japplphysiol.00176.2015
DO - 10.1152/japplphysiol.00176.2015
M3 - Article
C2 - 25930025
AN - SCOPUS:84937212292
SN - 8750-7587
VL - 119
SP - 69
EP - 76
JO - Journal of Applied Physiology
JF - Journal of Applied Physiology
IS - 1
ER -