Commercial Heat Packs do not Influence Cognitive Performance Following Cold Water Immersion
Abstract
Purpose: Exposure to cold water immersion (CWI) deteriorates cognitive performance, which negatively impacts warfighter readiness. Recovery of performance following CWI may be mediated by improving thermal perception, and application of commercially-available heat packs may facilitate such a response. This work evaluated the effects of exogenous heat application on temperature sensation and cognition following 10-min of CWI. Methods: Thirty-six participants (age: 28 + or - 6 yrs, 177 + or - 7 cm, 79.8 + or - 10.4 kg) had their heart rate, mean skin temperature (T sk), hand temperature (Thand), core temperature (Tc), thermal sensation (TS), shivering sensation (SS), and cognitive performance (match-to-sample (MTS) and simple reaction time (SRT)) measured during a CWI and rewarming exercise: pre-immersion, immersion, post-immersion, and at 0-min, 15-min, and 60-min of a rewarming exercise. Following post-immersion, participants changed into dry clothing and heat packs were applied to eight body sites for a treatment group. Results: Compared with pre-immersion, CWI elicited significant reductions in Tc (37.3 + or - 0.4 vs. 36.3 + or - 1.0 deg C), Thand (20.2 + or - 3.2 vs. 9.2 + or - 2.0 deg C), and T sk (28.9 + or - 2.5 vs. 14.1 + or - 1.4 deg C) and impaired cognitive performance (RTSRT: 278 + or - 29 vs. 321 + or - 58 ms). After 60-min rewarming, cognitive performance improved significantly compared to the start of rewarming (RTSRT: 287 + or - 28 vs. 333 + or - 71 ms; TCMTS: 22 + or - 2 vs. 20 + or - 3 trials correct). However, no group differences were observed for any cognitive measure between treatment and control, indicating that external heat application did not influence cognitive recovery.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 28, 2020
- Accession Number
- AD1138308
Entities
People
- Andrew Ordille
- Douglas Jones
- Jay Heaney
- Nicholas J Roberts
- Rebecca S. Weller
- Timothy Dunn
- Weimin Zheng
Organizations
- Naval Health Research Center