Effects of high occupational physical activity, aging, and exercise on heart rate variability among male workers

Table 4 Results of trend tests between heart rate variability items and occupational physical activity according to combined category of age and exercise

			SDNN				rMSSD				LF				HF				LF:HF
Age (year)	Exercise (frequency / week)	OPA	low		normal		low		normal		low		normal		low		normal		low		normal
Age (year)	Exercise (frequency / week)	OPA	n	%	n	%	n	%	n	%	n	%	n	%	n	%	n	%	n	%	n	%
< 45	≥3	Low	4	23.5	13	76.5	0	0.0	17	100.0	5	29.4	12	70.6	1	5.9	16	94.1	6	35.3	11	64.7
		High	1	10.0	9	90.0	0	0.0	10	100.0	2	20.0	8	80.0	0	0.0	10	100.0	5	50.0	5	50.0
		p-value	0.1911				na				0.2950				0.2172				0.2263
	1–2	Low	7	18.0	32	82.1	3	7.7	36	92.3	9	23.1	30	76.9	5	12.8	34	87.2	11	28.2	28	71.8
		High	3	21.4	11	78.6	0	0.0	14	100.0	3	21.4	11	78.6	0	0.0	14	100.0	6	42.9	8	57.1
		p-value	0.3876				0.1427				0.4497				0.0796				0.1568
	0	Low	4	26.7	11	73.3	2	13.3	13	86.7	4	26.7	11	73.3	1	6.7	14	93.3	5	33.3	10	66.7
		High	2	33.3	4	66.7	2	33.3	4	66.7	4	66.7	2	33.3	3	50.0	3	50.0	0	0.0	6	100.0
		p-value	0.3800				0.1458				0.0441				0.0112				0.0526
≥45	≥3	Low	2	25.0	6	75.0	0	0.0	8	100.0	3	37.5	5	62.5	1	12.5	7	87.5	4	50.0	4	50.0
		High	2	100.0	0	0.0	2	100.0	0	0.0	2	100.0	0	0.0	2	100.0	0	0.0	1	50.0	1	50.0
		p-value	0.0264				0.0008				0.0569				0.0079				0.5000
	1–2	Low	2	50.0	2	50.0	0	0.0	4	100.0	2	50.0	2	50.0	0	0.0	4	100.0	4	100.0	0	0.0
		High	2	66.7	1	33.3	1	33.3	2	66.7	2	66.7	1	33.3	1	33.3	2	66.7	0	0.0	3	100.0
		p-value	0.3296				0.1062				0.3296				0.1062				0.0041
	0	Low	0	0.0	1	100.0	0	0.0	1	100.0	0	0.0	1	100.0	0	0.0	1	100.0	1	100.0	0	0.0
		High	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0	0	0.0
		p-value	na				na				na				na				na

SDNN the standard deviation of normal-to-normal intervals, rMSSD the root-mean square of the difference of successive normal R-R intervals, LF low frequency band power, HF high frequency band power; LF:HF ratio of low-frequency power to high-frequency power, OPA occupational physical activity; na: not applicable

ISSN: 2052-4374