Table 2.

Comparison of the average daily amount of vitamin D intake and outdoor activities between the experimental and control groups.

Characteristics	Experimental group (n = 64)	Control group (n = 72)	p value
	Mean ± SD	Mean ± SD
Dietary vitamin D intake (μg/d)
Week 2	6.46 ± 3.63	6.30 ± 3.24	0.784
Week 4	6.34 ± 3.15	5.75 ± 2.76	0.245
Week 6	6.23 ± 3.21	5.54 ± 2.76	0.187
Time spent on outdoor activities (h/d)
Week 2	1.16 ± 1.16	0.96 ± 0.85	0.260
Week 4	1.13 ± 1.13	0.99 ± 0.90	0.432
Week 6	1.12 ± 1.11	0.99 ± 0.87	0.462

The independent t-test was performed and the data are presented as mean ± standard deviation.

Values refer to the total cumulative amount up to each assessment time point.