Table 3. Comparison of sleepiness, fatigue, and autonomic nervous activity between the two groups (6:00 to 9:00).

Variable	Group		p-value
	Nap	No nap
Temperature (°C)	36.62 (0.34)	36.86 (0.30)	0.02
HR (beat/min)	92.01 (9.83)	92.18 (9.12)	0.28
Sleepiness (VAS)	42.53 (31.64)	40.21 (21.42)	0.68
Fatigue (VAS)	49.91 (27.87)	50.68 (17.26)	0.9
HF (msec2/Hz)	135.76 (102.70)	157.84 (262.48)	0.07
LF/HF (ratio)	5.83 (3.21)	7.44 (3.37)	<0.001
Physical activity (mets)	2.21 (0.55)	2.16 (0.56)	0.13

Mean (SD), Fatigue (VAS) was examined by performing a t-test, and the other items by conducting a Mann-Whitney U test.