Stochastic resonance whole body vibration increases perceived muscle relaxation but not cardiovascular activation: A randomized controlled trial

Table 1 Mean values of study variables in verum stochastic resonance whole body vibration and sham stochastic resonance whole body vibration groups

Variable	Verum-SR-WBV (5 Hz SR-WBV) (n = 34)		Sham SR-WBV (1.5 Hz SR-WBV) (n = 30)		t	P
	Mean	SD	Mean	SD
Systolic blood pressure
Pre-training	129.67	12.78	120.9	9.68	3.05	0.003
Post-training	126.97	11.54	120.57	10.43	2.32	0.024
Diastolic blood pressure
Pre-training	78.61	11.00	75.27	7.64	1.39	0.171
Post-training	79.00	8.92	75.13	8.37	1.78	0.080
Heart rate
Pre-training	71.09	12.03	69.1	15.67	0.57	0.572
Post-training	69.94	11.51	68.4	13.25	0.50	0.620
Muscle relaxation
Pre-training	6.47	2.06	6.87	2.47	0.70	0.488
Post-training	7.00	2.10	6.7	2.59	0.51	0.611
Age (yr)	27.76	3.70	27.4	6.15	0.28	0.7791
Sex	18 f, 16 m		16 f, 14 m		χ2 = 0.001	0.975
BMI	22.58	2.59	21.68	2.80	1.34	0.187
Fitness	3.65	0.65	3.66	0.72	-0.05	0.963
Smoker (10 cigarettes or more)	12 (6)		7 (3)		χ2 = 1.09	0.296
Smoking (cigarettes)	3.53	6.33	2.30	6.98	0.74	0.463
Cups of coffee before training	1.50	1.11	1.67	1.47	-0.52	0.608
Back, neck or shoulder	2.71	1.00	2.63	1.40	0.24	0.8151
pain in last 12 mo

¹Corrected for unequal variances. BMI: Body mass index; SR-WBV: Stochastic resonance whole body vibration; f: Female; m: Male.

Table 2 Correlations between study variables

Variables	SR-WBVcondition	SBPpre	SBPpost	DBPpre	DBP post	HRpre	HRpost	Relax pre	Relaxpost	Age	Sex	BMI	Fitness	Smoking	Coffee
SR-WBV Condition
SBP pre	-0.36c
SBP post	-0.28a	0.83e
DBP pre	-0.18	0.63e	0.57e
DBP post	-0.22	0.59e	0.71e	0.68c
HR pre	-0.07	0.02	0.01	0.22	0.22
HR post	-0.06	0.03	0.07	0.21	0.24	0.76e
Relaxation pre	0.09	0.02	0.22	-0.04	0.01	0.04	-0.01
Relaxation post	-0.07	0.09	0.24	0.03	0.03	0.01	-0.04	0.84e
Age	-0.04	0.36c	0.40c	0.24	0.23	-0.03	-0.11	0.26a	0.26a
Sex	-0.01	0.26a	0.36c	-0.07	0.05	-0.16	-0.1	0.28a	0.15	0.29a
BMI	-0.17	0.08	0.14	-0.14	0	-0.32c	-0.19	-0.01	0.02	0.15	0.45e
Fitness	0.01	0.15	0.19	-0.13	-0.2	-0.19	-0.16	0.41c	0.38c	0.30a	0.34c	0.24
Smoking (number of cigarettes)	-0.09	0.10	0.07	-0.12	0.06	0.25a	0.37c	-0.01	-0.07	0.07	0.36c	0.28a	-0.02
Cups of coffee before training	0.07	0.09	0.01	-0.01	0.01	0.07	0.16	-0.28a	-0.28a	0.20	0.16	0.16	-0.18	0.33c
Back, neck or shoulder pain in last 12 mo	-0.03	-0.18	-0.30a	-0.04	-0.14	-0.08	0.03	-0.55e	-0.59e	-0.09	-0.27a	0.02	-0.26a	-0.03	0.24

^aP < 0.05,

^cP < 0.01,

^eP < 0.001: Correlations coefficients that significantly differ from zero. SR-WBV: Stochastic resonance whole body vibration; SBP: Systolic blood pressure; DBP: Diastolic blood pressure; HR: Heart rate.

Table 3 Results of two-factorial ANOVA

	Sum of squares	df	Mean square	F	P	Partial eta-square
Inner-subject effects
Pre- vs post-training (n = 64)	1.05	1	1.05	1.32	0.255	0.021
Training group (5 Hz vs 1.5 Hz)	3.86	1	3.86	4.85	0.031	0.073
Within subjects error	49.32	62	0.80
Between subjects effects
Constant	8.91	1	8.91	1.18	0.282	0.021
Training group (5 Hz vs 1.5 Hz)	0.74	1	0.74	0.01	0.931	0.000
Between subjects error	608.92	62	9.82