A Randomized Trial on the Effect of Bone Tissue on Vibration-induced Muscle Strength Gain and Vibration-induced Reflex Muscle Activity

Abstract

Whole-body vibration (WBV), as a method of exercise training, is becoming increasingly popular in physical therapy, rehabilitation, and professional sports, and is increasingly used in beauty and wellness applications due to its beneficial effects on the neuromusculoskeletal system. These benefits include improved strength, power, flexibility, jump height, and balance (1-4).However, little is known about the physiological mechanisms underlying the effects of WBV on muscular performance, although the presence of reflex muscle activity during WBV has been shown (4, 5). Tonic vibration reflex (TVR) is the most commonly cited mechanism to explain the effects of WBV on muscular performance, although there is no conclusive evidence that tonic vibration reflex (TVR) occurs (4-6). Studies have reported that direct vibration applied to a muscle or tendon stimulates muscle spindles, thereby causing a TVR to occur. As highlighted by these studies, muscle spindle Background: Whole-body vibration (WBV) induces reflex muscle activity and leads to increased muscle strength. However, little is known about the physiological mechanisms underlying the effects of whole-body vibration on muscular performance. Tonic vibration reflex is the most commonly cited mechanism to explain the effects of whole-body vibration on muscular performance, although there is no conclusive evidence that tonic vibration reflex occurs. The bone myoregulation reflex is another neurological mechanism used to explain the effects of vibration on muscular performance. Bone myoregulation reflex is defined as a reflex mechanism in which osteocytes exposed to cyclic mechanical loading induce muscle activity. Aims: The aim of this study was to assess whether bone tissue affected vibration-induced reflex muscle activity and vibration-induced muscle strength gain. Study Design: A prospective, randomised, controlled, double-blind, parallel-group clinical trial. Methods: Thirty-four participants were randomised into two groups. High-magnitude whole-body vibration was applied in the exercise group, whereas low-magnitude whole-body vibration exercises were applied in the control group throughout 20 sessions. Hip bone mineral density, isokinetic muscle strength, and plasma sclerostin levels were measured. The surface electromyography data were processed to obtain the Root Mean Squares, which were normalised by maximal voluntarily contraction. Results: In the exercise group, muscle strength increased in the right and left knee flexors (23.9%, p=0.004 and 27.5%, p<0.0001, respectively). However, no significant change was observed in the knee extensor muscle strength. There was no significant change in the knee muscle strength in the control group. The vibration-induced corrected Root Mean Squares of the semitendinosus muscle was decreased by 2.8 times (p=0.005) in the exercise group, whereas there was no change in the control group. Sclerostin index was decreased by 15.2% (p=0.031) in the exercise group and increased by 20.8% (p=0.028) in the control group. A change in th...

Influence of Whole-Body Vibration Training Without Visual Feedback on Balance and Lower-Extremity Muscle Strength of the Elderly

“…Osteocytes exposed to mechanical loading will transmit input information to the central nervous system and affect neuronal regulation. 39 , 40 If individuals stand with their knees slightly bent, WBV will generate hyper gravity and increase the extension moment of the knee joints, which may increase the mechanical loading on a cross-sectional area of the femur. If the osteocytes in the area are exposed to stronger mechanical stimulation, osteocyte compression will increase.…”

“…Therefore, based on the BMR mechanism, WBV leads to an increase in muscle strength, in addition to an increase in bone mineral density, through the reflex of muscle activity caused by mechanical loading. 39 , 40 …”

Plyometrics and vibration: no clear winner on efficacy

“…Very few studies regarding WBV currently exist in regards to controlling for the subject's activity level. Most studies involve subjects that are either athletes [4,6] or active, but not trained [5,9]. Plyometric training has had a significant influence in the trained athlete, so most of its understanding has been focused with that population [23,28,29].…”

“…WBV started initially as a training tool to help increase strength and physical performance (i.e., jumping) [6,[9][10][11]. Several studies have been performed showing physiological benefits with increased VO 2 [2], skin blood flow [12], and bone mineral density [13].…”

Effects of whole body vibration exercises on functional parameters of individuals with chronic obstructive pulmonary disease

“…WBVE induces muscle contractions through involuntary reflex and may be useful to aid in the treatment of COPD individuals. 27 In addition, WBVE could also be responsible for neuro-endocrine responses 28 . In this way, WBVE can be an option in the management of individuals with COPD, used as a PA in the PR protocol, 29 in an effective, safe and viable intervention.…”