. 2022 May 3;323(1):R1–R15. doi: 10.1152/ajpregu.00021.2022

Table 4.

Physiological and perceptual responses obtained during the baseline, the body immersion, the 30-min hand cold-water immersion, the 15-min hand-rewarming, and the 30-min body-rewarming phases in the normothermic provocation trials, performed before and after the 5-day acclimation regimen

	Preacclimation					Postacclimation
	Baseline	B-WI	H-CWI	H-RW	B-RW	Baseline	B-WI	H-CWI	H-RW	B-RW
CA group
T_rec, °C	37.1 [36.9, 37.4]	37.1 [36.9, 37.3]	37.1 [36.9, 37.4]	37.1 [36.8, 37.4]	37.1 [36.9, 37.3]	37.1 [36.9, 37.4]	37.1 [36.9, 37.3]	37.1 [36.9, 37.4]	37.0 [36.8, 37.3]	37.1 [36.8, 37.3]
T_sk, °C	33.9 [33.3, 34.5]	34.9 [34.6, 35.1]	34.8 [34.5, 35.0]	34.8 [34.7, 34.9]	34.6 [34.4, 34.8]	33.8 [33.2, 34.4]	34.8 [34.6, 35.0]	34.6 [34.4, 34.9]	34.6 [34.3, 34.9]	34.6 [34.2, 35.0]
${\bar{T}}_{b}$ , °C	36.0 [35.6, 36.3]	36.3 [36.1, 36.5]	36.3 [36.1, 36.5]	36.3 [36.1, 36.5]	36.2 [36.1, 36.4]	35.9 [35.6, 36.3]	36.3 [36.1, 36.5]	36.2 [36.0, 36.5]	36.2 [36.0, 36.4]	36.2 [35.9, 36.4]
$\dot{M}$ , W	128 [107, 148]	132 [107, 157]	128 [106, 149]	124 [104, 145]	127 [110, 144]	126 [113, 139]	129 [116, 143]	128 [117, 138]	126 [114, 137]	122 [108, 137]
SAP, mmHg	123 [116, 131]	108 [101, 114]	117 [110, 124]	114 [107, 121]	121 [111, 130]	121 [111, 130]	105 [92, 118]	110 [100, 121]	110 [102, 119]	121 [108, 135]
DAP, mmHg	74 [67, 80]	62 [56, 69]	67 [60, 73]	64 [57, 71]	70 [60, 79]	72 [61, 83]	60 [49, 72]	61 [53, 66]†	62 [54, 69]	70 [58, 81]
MAP, mmHg	91 [84, 97]	78 [72, 84]	85 [78, 91]	82 [75, 88]	87 [78, 96]	89 [79, 100]	76 [64, 89]	78 [69, 88]	79 [70, 87]	88 [75, 100]
HR, beats/min	72 [68, 76]	70 [66, 74]	70 [67, 73]	67 [63, 70]	69 [63, 75]	70 [61, 79]	69 [61, 76]	67 [60, 74]	66 [60, 73]	66 [59, 74]
Body thermal sensation	5.2 (5–6)	4.9 (4–6)	4.7 (4–6)	4.9 (4–6)	5.0 (4–6)	5.2 (4–6)	5.7 (5–6)*	5.2 (5–6)	5.2 (4–6)	5.4 (4–6)*
Body thermal comfort	1	1	1	1	1	1	1	1	1	1
Affective valence	2.9 (1 to 5)	3.0 (1 to 5)	1.1 (−1 to 4)	2.0 (0 to 4)	2.3 (0 to 4)	1.9 (0 to 4)	2.5 (0 to 5)	2.0 (0 to 5)	2.5 (0 to 5)	2.5 (0 to 5)
CON group
T_rec, °C	37.2 [37.1, 37.2]	37.1 [37.0, 37.2]	37.1 [37.0, 37.3]	37.1 [37.0, 37.3]	37.1 [36.9, 37.2]	37.1 [37.0, 37.3]	37.0 [36.9, 37.2]	37.1 [37.0, 37.2]	37.1 [37.0, 37.2]	37.0 [36.9, 37.2]
T_sk, °C	33.8 [33.4, 34.2]	34.9 [34.7, 35.1]	34.7 [34.5, 35.0]	34.6 [34.3, 34.9]	34.5 [34.2, 34.9]	33.6 [33.5, 33.8]	34.9 [34.7, 35.1]	34.7 [34.4, 34.9]	34.5 [34.2, 34.9]	34.3 [34.0, 34.6]
${\bar{T}}_{b}$ , °C	36.0 [35.8, 36.1]	36.3 [36.2, 36.4]	36.3 [36.1, 36.4]	36.2 [36.0, 36.4]	36.2 [36.0, 36.3]	35.9 [35.7, 36.0]	36.3 [36.2, 36.4]	36.2 [36.1, 36.3]	36.2 [36.0, 36.3]	36.1 [36.0, 36.2]
$\dot{M}$ , W	131 [113, 149]	139 [124, 154]	140 [122, 159]	137 [118, 157]	137 [121, 152]	124 [108, 139]	128 [110, 146]	131 [115, 147]	129 [116, 141]	126 [111, 140]
SAP, mmHg	115 [105, 125]	104 [95, 114]	119 [109, 130]	117 [109, 125]	127 [118, 137]	119 [111, 126]	107 [100, 113]	120 [110, 130]	117 [105, 130]	132 [118, 145]
DAP, mmHg	67 [63, 71]	56 [52, 61]	64 [59, 69]	65 [60, 69]	75 [67, 83]	71 [66, 77]	61 [56, 67]	67 [59, 75]	66 [57, 75]	79 [68, 89]
MAP, mmHg	85 [80, 89]	74 [69, 79]	85 [78, 91]	84 [78, 90]	94 [86, 103]	89 [83, 94]	78 [72, 84]	86 [76, 96]	84 [74, 95]	97 [86, 109]
HR, beats/min	69 [63, 75]	69 [63, 74]	69 [62, 75]	67 [60, 75]	67 [61, 73]	69 [63, 76]	68 [61, 74]	67 [62, 73]	65 [59, 71]	67 [61, 72]
Body thermal sensation	5.1 (4–6)	5.3 (5–6)	4.6 (4–6)	4.6 (4–6)	4.8 (4–6)	4.5 (4–6)	5.2 (5–6)	4.7 (4–6)	4.6 (4–6)	4.7 (4–6)
Body thermal comfort	1	1	1	1	1	1	1	1	1	1
Affective valence	2.9 (0 to 5)	2.9 (0 to 5)	1.8 (−1 to 5)	2.4 (0 to 5)	2.4 (0 to 5)	2.9 (0 to 5)	2.8 (0 to 5)	1.9 (−1 to 5)	2.3 (−1 to 5)	2.6 (0 to 5)

Data are the mean of the entire phase. Values are mean [95% confidence intervals] for rectal (T_rec), skin (T_sk) and mean body ( ${\bar{T}}_{b}$ ) temperatures, metabolic heat production ( $\dot{M}$ ), systolic (SAP), diastolic (DAP), and mean (MAP) arterial pressures, and heart rate (HR). Values are mean (range) for thermal sensation and comfort, and affective valence. Physiological data were analyzed with two-way repeated-measures ANOVA, followed by Duncan’s multiple range test. Perceptual data were analyzed with Kruskal–Wallis’ test, followed by either Mann–Whitney U or Wilcoxon signed-rank test (P ≤ 0.05). B-WI, body water-immersion; B-RW, 30-min body-rewarming; CA group, cold-acclimation group (n = 7 men); CON group, control group (n = 7 men). H-CWI, 30-min hand cold-water immersion; H-RW, 15-min hand-rewarming.

Significantly different from the preacclimation trial (*) and from the CON group (†).