Effect of skin wetting on ventilatory and perceptual responses to exercise heat stress in well-healed burn survivors

Well-healed burn survivors experience higher rates of cardiovascular disease, diabetes, and obesity compared to individuals without a burn injury. These responses are likely due to, in part, a lower adherence to exercise associated with impaired thermoregulation, decreased mobility and range of motion from scar tissue, and psychological barriers to exercise. Our goal is to improve thermal comfort during exercise in burn survivors through whole-body skin wetting with cool water, thus “minimizing” a barrier to exercise adherence in this population. In addition to improving thermal comfort, cooling of the skin during heat stress decreases heat-induced hyperventilation in non-burned individuals and may do the same in burn survivors, thereby improving exercise comfort and adherence. Purpose: We tested the hypothesis that whole body skin wetting (with cool water) would attenuate ventilatory responses in burn survivors, but not in controls, during one hour of moderate intensity exercise in the heat. Methods: Participants completed two experimental visits that required 1-hour of moderate intensity (5 METs) cycling in the heat (41°C, 15% humidity) with and without whole-body skin wetting (randomized) with cool (~24°C) water. We measured core temperature, ventilation, expired gases, rating of thermal comfort and sensation, and rating of perceived exertion (RPE). We used paired t-tests to compare responses between the control and the water spray trials for each of the three groups (non-burned controls, moderate burn, and high burn). Results: Thirty participants completed the protocol: 10 non-burned controls, 10 with moderate burn injuries (26 ± 8% BSA burn injured), and 10 with high burn injuries (59 ± 15% BSA burn injured). There was no difference in the change in core temperature between the control and water spray trials in the non-burned group (C: Δ1.03 ± 0.38°C; WS: Δ1.02 ± 0.38°C; p = 0.859), moderate burn group (C: Δ0.99 ± 0.41°C; WS: Δ0.96 ± 0.34°C; p =0.437) or high burn group (C: Δ1.39 ± 0.48°C; WS: Δ1.16 ± 0.56°C; p = 0.105). Similarly, there was no difference in end-exercise ventilation between the control and water spray trials in the non-burned group (C: 42 ± 12 L/min; WS: 41 ± 10 L/min; p = 0.401), moderate burn group (C: 48 ± 10 L/min; WS: 47 ± 10 L/min; p = 0.500) or high burn group (C: 46 ± 10 L/min; WS: 44 ± 10 L/min; p = 0.286). Additional ventilatory parameters such as end exercise Ve/VCO2, end exercise breathing frequency, or end exercise tidal volume were not different between the control and water spray trials in any group (p = 0.308 – 0.993). Nevertheless, thermal sensation improved such that participants felt warmer during the control trial compared to the water spray trial in the non-burned group (C: 27 ± 5; WS: 16 ± 8; p < 0.001), moderate burn group (C: 34 ± 7; WS: 24 ± 13; p = 0.003) and the high burn group (C: 39 ± 9; WS: 21 ± 14; p = 0.021). Conclusion: Whole-body skin wetting with cool temperature water results in the exercise in the heat feeling more “comfortable” or “tolerable” in both well-healed burn survivors and control participants, which we contend would improve exercise adherence in all groups. Notably, these perceptual responses are not attributable to differences in ventilation or core temperatures with skin wetting. Supported by NIH 5R01GM068865-16 (CGC) and NIH R35GM152112 (CGC) This abstract was presented at the American Physiology Summit 2026 and is only available in HTML format. There is no downloadable file or PDF version. The Physiology editorial board was not involved in the peer review process.