Table 1.
Thermophysiological and cardiovascular parameters during low‐intensity exercise (LEX), moderate intensity exercise (MEX) and passive heating (PH) at baseline (BL) and at 5‐min stages throughout each protocol
| BL | 5 min | 10 min | 15 min | 20 min | 25 min | 30 min | Sign | ||
|---|---|---|---|---|---|---|---|---|---|
| Tes (˚C) | LEX | 36.9 ± 0.2 | 36.8 ± 0.2# | 37.0 ± 0.2*, # | 37.1 ± 0.2*, $, # | 37.1 ± 0.2*, $, # | 37.2 ± 0.2*, $, # | 37.2 ± 0.2*, $, # | # ϕ |
| MEX | 36.9 ± 0.3 | 37.0 ± 0.3# | 37.5 ± 0.4*, #, ϕ | 37.7 ± 0.4*, #, ϕ | 37.9 ± 0.5*, #, ϕ | 38.1 ± 0.6*, #, ϕ | 38.3 ± 0.7*, #, ϕ | ||
| PH | 36.9 ± 0.4 | 36.9 ± 0.4 | 37.1 ± 0.4*, ϕ | 37.5 ± 0.4*, $, ϕ | 37.4 ± 0.4*, $, ϕ | 37.5 ± 0.4*, $, ϕ | 37.6 ± 0.4*, $, ϕ | ||
| Tb (˚C) | LEX | 36.3 ± 0.2 | 36.2 ± 0.3$ | 36.3 ± 0.5*, $, # | 36.4 ± 0.4*, $, # | 36.5 ± 0.4*, $, # | 36.5 ± 0.4*, $, # | 36.6 ± 0.4*, $, # | $ # |
| MEX | 36.4 ± 0.4 | 36.3 ± 0.4ϕ | 36.7 ± 0.7*, # | 37.0 ± 0.7*, # | 37.2 ± 0.8*, # | 37.4 ± 0.8*, # | 37.5 ± 0.9*, # | ||
| PH | 36.4 ± 0.4 | 36.7 ± 0.3ϕ | 37.0 ± 0.4*, $ | 37.2 ± 0.4*, $ | 37.4 ± 0.4*, $ | 37.5 ± 0.3*, $ | 37.5 ± 0.3*, $ | ||
| Mean Tsk (˚C) | LEX | 34.2 ± 0.5$ | 34.1 ± 0.5$ | 34.3 ± 0.6*, $ | 34.3 ± 0.6*, $ | 34.4 ± 0.6*, $ | 34.4 ± 0.6*, $ | 34.5 ± 0.5*, $ | $ # ϕ |
| MEX | 34.2 ± 0.5 | 34.2 ± 0.4ϕ | 34.6 ± 0.6*, #, ϕ | 35.1 ± 0.6*, #, ϕ | 35.3 ± 0.5*, #, ϕ | 35.5 ± 0.5*, #, ϕ | 35.5 ± 0.5*, #, ϕ | ||
| PH | 34.4 ± 0.5$ | 35.9 ± 0.5$, ϕ | 36.5 ± 0.6*, $, ϕ | 36.8 ± 0.7*, $, ϕ | 37.0 ± 0.6*, $, ϕ | 37.1 ± 0.4*, $, ϕ | 37.2 ± 0.4*, $, ϕ | ||
| HR (bpm) | LEX | 63.3 ± 10.7 | 91.5 ± 10.4*, $, # | 94.3 ± 11.5*, # | 96.8 ± 10.7*, # | 98.8 ± 11.3*, # | 98.6 ± 11.5*, # | 99.4 ± 11.8*, # | $ # ϕ |
| MEX | 64.5 ± 9.6 | 116.1 ± 13.8*, ϕ | 133.7 ± 10.3*, ϕ | 144.8 ± 12.1*, ϕ | 148.2 ± 12.3*, ϕ | 150.4 ± 12.2*, ϕ | 151.9 ± 11.2*, ϕ | ||
| PH | 64.8 ± 10.8 | 73.6 ± 16.4$, ϕ | 80.5 ± 22.1ϕ | 85.4 ± 23.3*, ϕ | 88.7 ± 22.3*, ϕ | 91.1 ± 20.9*, ϕ | 93.4 ± 20.3*, ϕ | ||
| MAP (mmHg) | LEX | 92.3 ± 9.5 | 98.3 ± 7.8# | 100.2 ± 8.6# | 99.5 ± 9.3# | 99.3 ± 9.0# | 99.5 ± 8.0# | 99.2 ± 8.5# | $ # ϕ |
| MEX | 93.2 ± 8.0 | 120.5 ± 14.7*, #, ϕ | 116.8 ± 11.7*, #, ϕ | 111.8 ± 10*, #, ϕ | 111.7 ± 9.5*, #, ϕ | 112.0 ± 10.9*, #, ϕ | 112.3 ± 10.3*, #, ϕ | ||
| PH | 93.8 ± 8.8 | 97.7 ± 11.9ϕ | 98.6 ± 13.1ϕ | 96.2 ± 12.1ϕ | 94.2 ± 11ϕ | 94.1 ± 10ϕ | 95.1 ± 9.9ϕ |
Values are means ± SD for 12 participants measured at baseline (BL) and over 5 minute periods during three different conditions; LEX, low‐intensity exercise, MEX, moderate intensity exercise; PH, passive heating. HR, heart rate; MAP, mean arterial pressure. Two‐way ANOVA revealed a main effect of condition and time for all variables presented in this table. Post hoc comparison for condition is indicated by the following: $for LEX vs. PH, # for LEX vs. MEX, and ϕ for MEX vs. PH (all P < 0.05). Post hoc comparisons of time are indicated by *(P < 0.05), which shows where the time point was higher than baseline (BL). An interaction effect was observed between time and condition for all variables as indicated by $ for LEX vs. PH, # for LEX vs. MEX, and ϕ for MEX vs. PH (all P < 0.05).