Table 4. Changes in the biochemical parameters and physical activity level.

Variables		Placebo (n = 37)				Collagen (n = 37)				p value†
		Baseline	12 weeks	Changes	p value*	Baseline	12 weeks	Changes	p value*
Biochemical parameters
	Total cholesterol (mg/dL)	200.4 ± 40.6	200.9 ± 42.5	0.5 ± 22.0	0.882	191.7 ± 44.0	190.2 ± 42.2	−1.5 ± 24.6	0.710	0.706
	Serum glucose (mg/dL)	102.8 ± 22.2	107.2 ± 24.4	4.4 ± 25.7	0.307	103.7 ± 16.2	102.8 ± 13.5	−0.9 ± 11.9	0.660	0.263
	HDL cholesterol (mg/dL)	57.0 ± 14.5	57.1 ± 14.8	0.1 ± 8.4	0.938	58.0 ± 11.4	57.4 ± 12.1	−0.6 ± 6.8	0.613	0.705
	LDL cholesterol (mg/dL)	123.2 ± 37.8	123.8 ± 39.2	0.7 ± 18.6	0.834	117.8 ± 39.6	116.3 ± 39.2	−1.5 ± 21.7	0.685	0.655
	Triglyceride (mg/dL)	133.2 ± 71.3	127.7 ± 74.2	−5.6 ± 38.6	0.383	118.7 ± 56.2	113.4 ± 49.3	−5.3 ± 44.2	0.468	0.978
Physical activity level
	IPAQ (METs)‡	2,828.9 ± 2,001.7	3,191.8 ± 2,455.7	362.9 ± 2,144.4	0.310	3,086.6 ± 2,809.1	3,432.9 ± 2,319.0	346.3 ± 2,568.7	0.418	0.976

Date are presented as means ± standard deviations.

The participants take a collagen peptide supplement (15 g/day) or a placebo once daily during the 12-week intervention period.

No statistically significant differences in biochemical parameters and physical activity level were found between the collagen and placebo groups.

HDL, high-density lipoprotein; LDL, low-density lipoprotein; IPAQ, international physical activity questionnaire; MET, metabolic equivalent task.

^*No significant difference by the paired t-test at p < 0.05; ^†No significant difference by the independent t-test at p < 0.05; ^‡The score is calculated using the IPAQ, with a higher score indicating greater physical activity.