Elastic Tubing Resistance Training and Autonomic Modulation in Subjects with Chronic Obstructive Pulmonary Disease

Table 3

Intragroup differences for heart rate variability, muscle strength, and walking distance between the moments before and after training.

Descriptive	Elastic tubing; ()			Conventional training; ()
	Before	After		Before	After
Heart rate variability
rMSSD (ms)	12,65 (15,10)	19,70 (12,63)	0,015	12,50 (10,50)	16,60 (11,70)	0,040
SDNN (ms)	22,45 (20,85)	28,20 (17,55)	0,263	18,90 (12,10)	22,80 (16,90)	0,184
LF (ms^2)	116,00 (309,00)	182,00 (349,00)	0,575	65,00 (83,00)	150,00 (264,00)	0,099
HF (ms^2)	75,00 (187,00)	160,00 (228,50)	0,021	30,00 (121,00)	54,00 (149,00)	0,024
LF/HF ratio	1,41 (1,88)	1,63 (1,99)	0,970	2,47 (2,44)	1,70 (3,44)	0,159
VLF (ms)	203,00 (330,00)	260,00 (443,75)	0,526	116,00 (194,00)	222,00 (503,00)	0,064
Total power (%)	500,00 (837,50)	505,00 (740,00)	0,823	240,00 (296,00)	526,00 (830,00)	0,033
TINN (ms)	87,50 (72,50)	110,00 (75,00)	0,184	65,00 (70,00)	95,00 (70,00)	0,029
RRtri	6,01 (4,02)	7,22 (4,15)	0,062	5,57 (3,18)	5,69 (5,59)	0,064
SD1 (ms)	8,95 (10,75)	13,95 (8,88)	0,014	8,90 (7,40)	8,20 (8,30)	0,036
SD2 (ms)	30,60 (27,53)	37,55 (23,55)	0,390	25,50 (16,50)	29,60 (23,90)	0,191
SD1/SD2	0,34 (0,13)	0,37 (0,21)	0,681	0,30 (0,15)	0,33 (0,17)	0,857
Muscle strength and walking distance
Knee flexion (N)	101,91 ± 34,00	116,79 ± 43,31	0,030	98,58 ± 21,46	115,13 ± 30,80	0,003
Knee extension (N)	197,18 ± 75,64	208,98 ± 78,44	0,121	194,10 ± 55,50	214,00 ± 53,58	0,059
Shoulder flexion (N)	59,60 ± 19,59	64,01 ± 23,72	0,196	52,57 ± 19,81	61,81 ± 19,38	0,008
Shoulder abduction (N)	50,11 ± 19,62	56,89 ± 20,37	0,039	50,51 ± 18,99	56,94 ± 19,33	0,009
Elbow flexion (N)	106,24 ± 60,56	107,15 ± 55,91	0,135	109,35 ± 42,08	116,80 ± 42,81	0,367
6MWT (m)	433,03 ± 84,77	468,85 ± 90,79	0,041	397,37 ± 99,83	426,26 ± 101,58	0,001

: significance level by Wilcoxon test or “b” for Student’s -test for paired data; ms: milliseconds; ms²: squared milliseconds; rMSSD: the root mean square of successive difference between consecutive heart beats; SDNN: the standard deviation of normal-to-normal intervals; LF: low frequency; HF: high frequency; VLF: very low frequency; TINN: triangular interpolation of the interval between consecutive heart beats; RRtri: triangular index; SD1: standard deviation of instant variability; SD2: standard deviation of long-term interval between consecutive heart beats; 6MWT: distance walked in the six-minute walking test; N: Newton; m: meters. Values are expressed as median (interquartile range) or mean ± standard deviation.