Effects of whole-body vibration exercise on the endocrine system of healthy men

Abstract

Whole-body vibration is reported to increase muscle performance, bone mineral density and stimulate the secretion of lipolytic and protein anabolic hormones, such as GH and testosterone, that might be used for the treatment of obesity. To date, as no controlled trial has examined the effects of vibration exercise on the human endocrine system, we performed a randomized controlled study, to establish whether the circulating concentrations of glucose and hormones (insulin, glucagon, cortisol, epinephrine, norepinephrine, GH, IGF-1, free and total testosterone) are affected by vibration in 10 healthy men [age 39 +/- 3, body mass index (BMI) of 23.5 +/- 0.5 kg/m2, mean +/- SEM]. Volunteers were studied on two occasions before and after standing for 25 min on a ground plate in the absence (control) or in the presence (vibration) of 30 Hz whole body vibration. Vibration slightly reduced plasma glucose (30 min: vibration 4.59 +/- 0.21, control 4.74 +/- 0.22 mM, p=0.049) and increased plasma norepinephrine concentrations (60 min: vibration 1.29 +/- 0.18, control 1.01 +/- 0.07 nM, p=0.038), but did not change the circulating concentrations of other hormones. These results demonstrate that vibration exercise transiently reduces plasma glucose, possibly by increasing glucose utilization by contracting muscles. Since hormonal responses, with the exception of norepinephrine, are not affected by acute vibration exposure, this type of exercise is not expected to reduce fat mass in obese subjects.

The effects of whole body vibration and exercise on fibrinolysis in men

“…Di Loreto (20) et al examined the effects of WBV on the human endocrine system. He recruited 10 healthy male subjects (age 39 ± 3, BMI of 23.5 ± 0.5 kg·mˉ², mean ± SEM) for this study.…”

Whole body vibration and blood glucose levels in elderly people: a pilot study

“…This exercise mediated process is similar to the action of the insulin on glucose uptake, which also involves translocation of GLUT-4 glucose transporters [6,[16][17]. The present study did not measure GLUT-4 translocation to confirm this hypothesis; it was limited to verify blood glucose levels.…”

“…Some studies have shown that a single bout of muscle contractions leads to GLUT 4 translocation to the plasma membrane and transverse tubules of contracting muscles, which acutely enhances glucose transport capacity [6,[16][17].…”

“…Di Loreto et al [17] have studied the effect of a single session of WBV on the endocrine system of 10 healthy individuals and the results showed an increased GLUT 4 translocation. Although similar effects on blood glucose were observed in the present study, several methodological differences can be listed when comparing both studies.…”

“…Firstly, the mean age of those subjects was 39±3 years (range 25-50 years), while the present study included only elderly subjects. Additionally, they used a non-continuous 30 Hz vibration protocol with a duration of 25 min and rest phases [17]. In contrast, the present study used a continuous 20 Hz vibration protocol.…”