AUTHOR=Seeley Afton D. , Sherman Ross A. 

TITLE=An Ice Vest, but Not Single-Hand Cooling, Is Effective at Reducing Thermo-Physiological Strain During Exercise Recovery in the Heat

JOURNAL=Frontiers in Sports and Active Living

VOLUME=Volume 3 - 2021

YEAR=2021

URL=https://www.frontiersin.org/journals/sports-and-active-living/articles/10.3389/fspor.2021.660910

DOI=10.3389/fspor.2021.660910

ISSN=2624-9367

ABSTRACT=Sports limit the length of breaks between halves or periods, placing substantial time constraints on cooling effectiveness. This study investigated the effect of active cooling during both time-limited and prolonged post-exercise recovery in the heat. Ten recreationally-active adults (VO2peak 43.6 ± 7.5 ml∙kg-1∙min-1) were exposed to thermally-challenging conditions (36°C air temperature, 45% RH) while passively seated for 30 minutes, cycling for 60 minutes at 51% VO2peak, and during a seated recovery for 60 minutes that was broken into two epochs: first 15 minutes (REC0-15) and total 60 minutes (REC0-60). Three different cooling techniques were implemented during independent recovery trials: (a) negative-pressure single hand-cooling (~17°C); (b) ice vest; and (c) non-cooling control. Change in rectal temperature (Tre), mean skin temperature (¯Tsk), heart rate (HR) and thermal sensation (TS), as well as mean body temperature (¯Tb), and heat storage (S) were calculated for exercise, REC0-15 and REC0-60. During REC0-15, HR was lowered more with the ice vest (-9 [-15 to -3] bts·min-1, p=.002) and single hand-cooling (-7 [-13 to -1] bts·min-1, p=.021) compared to a non-cooling control. The ice vest caused a greater change in ¯Tsk compared to no cooling (-1.07 [-2.00 to -0.13]°C, p=.021) and single-hand cooling (-1.07 [-2.01 to -0.14]°C, p=.020), as well as a greater change in S compared to no cooling (-84 [-132 to -37] W, p<.0001) and single-hand cooling (-74 [-125 to -24] W, p=.002). Across REC0-60, changes in ¯Tb (-0.38 [-0.69 to -0.07]°C, p=.012) and ¯Tsk (-1.62 [-2.56 to -0.68]°C, p<.0001) were greater with ice vest compared to no cooling. Furthermore, changes in in ¯Tb (-0.39 [-0.70 to -0.08]°C, p=.010) and ¯Tsk (-1.68 [-2.61 to -0.74]°C, p<.0001) were greater with the ice vest compared to single-hand cooling.  Using an ice vest during time-limited and prolonged recovery in the heat aided in a more effective reduction in thermo-physiological strain compared to both passive cooling as well as a single-hand cooling device.