Whole-body vibration as a potential countermeasure for dynapenia and arterial stiffness

Relationship between Muscle Mass and Muscle Strength with Bone Density in Older Adults: A Systematic Review

BACKGROUND

Understanding the relationship between muscle mass, muscle strength, and bone density in older adults is crucial for addressing age-related conditions like osteoporosis and sarcopenia. This review aims to evaluate the relationship between muscle mass and muscle strength with bone density in older adults.

METHODS

This systematic review, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, involved a comprehensive search across seven databases from 2014 to April 2024. Included were observational studies in English and Indonesian on adults aged 60 and older. The Appraisal Tool for Cross-Sectional Studies (AXIS) tool assessed the risk of bias, and the GRADE (Grading of Recommendations Assessment, Development, and Evaluation) framework evaluated the evidence quality. Study selection was independently reviewed, and consensus was reached through discussion.

RESULTS

Ten studies were included. For muscle mass and bone density, five studies showed a significant association, while four did not. For muscle strength and bone density, four of seven studies reported a significant association. However, the evidence quality was low due to inconsistency.

CONCLUSION

The relationship between muscle mass, muscle strength, and bone density in older adults shows variability and inconsistent evidence.

Comparison of aerobic and combined aerobic and whole-body vibration training effects on physical fitness in non-alcoholic fatty liver patients

The aim of this study was to evaluate the effectiveness of exercises with whole-body vibration which was added to aerobic training on the physical fitness of patients with non-alcoholic fatty liver disease. Thirty-two patients diagnosed with non-alcoholic fatty liver (age 44.39±8.74 years) were randomly divided into an aerobic training + vibration group and an aerobic training + sham vibration group. The aerobic training was continued at 60-80% heart rate workload, 40 min per day during 3 days per week, for 8 weeks. Vibration were performed with dynamic and static exercises at 30 Hz, with a 2 mm amplitude, for 15 min. The energy expenditure responses were carried out by an exercise tolerance test system. Lower limb isometric muscle strength assessment was made with a calibrated handheld dynamometer from bilaterally knee extensors. The sit to stand test, and the time up and go test were used for physical performance evaluation. At eight weeks, both groups showed a significant reduction in the sit to stand (-1.62±1.00 vs -0.37±1.52), the time up and go test (-1.43±0.99 vs -1.39±1.06), the right lower extremity muscle strength (1.01±1.61 vs 1.22±2.82), and the energy expenditure scores (MET; 1.88 ml/kg/min, 95% confidence interval (CI) 1.19; 2.57, d=0.55, minimal clinically important difference (McID) = 0.69 vs 2.01 ml/kg/min, 95% CI 0.76; 3.24, d=0.26, McID = 1.54, respectively), however no significant differences emerged between groups (P≥0.05). The addition of vibration exercises to an aerobic program did not provide additional benefits to physical fitness in patients with non-alcoholic fatty liver.

Effects of centrifugation and whole-body vibrations on blood-brain barrier permeability in mice

Modifications of gravity levels induce generalized adaptation of mammalian physiology, including vascular, brain, muscle, bone and immunity functions. As a crucial interface between the vascular system and the brain, the blood–brain barrier (BBB) acts as a filter to protect neurons from pathogens and inflammation. Here we compare the effects of several protocols of hypergravity induced by centrifugation and whole-body vibrations (WBV) on BBB integrity. The immunohistochemistry revealed immunoglobulin G (IgG) extravasation from blood to hippocampal parenchyma of mice centrifuged at 2 × g during 1 or 50 days, whereas short exposures to higher hypergravity mimicking the profiles of spaceflight landing and take-off (short exposures to 5 × g) had no effects. These results suggest prolonged centrifugation (>1 days) at 2 × g induced a BBB leakage. Moreover, WBV were similarly tested. The short exposure to +2 × g vibrations (900 s/day at 90 Hz) repeated for 63 days induced IgG extravasation in hippocampal parenchyma, whereas the progressive increase of vibrations from +0.5 to +2 × g for 63 days was not able to affect the IgG crossing through the BBB. Overall, these results suggest that the BBB permeability is sensitive to prolonged external accelerations. In conclusion, we advise that the protocols of WBV and centrifugation, proposed as countermeasure to spaceflight, should be designed with progressively increasing exposure to reduce potential side effects on the BBB.

Assessment Through the Short Physical Performance Battery of the Functionality in Individuals With Metabolic Syndrome Exposed to Whole-Body Vibration Exercises

Physical activity is recommended in the management of individuals with metabolic syndrome (MetS), and recent studies have suggested whole-body vibration exercise (WBVe) for this population. The aim of this study was to evaluate the functionality through the Short Physical Performance Battery (SPPB) in individuals with MetS after WBVe. The SPPB evaluates the balance, the gait speed, and the lower limb strength (five-chair stand [5CS] test). Forty-four individuals with MetS were divided into WBVe (WBVeG) and control (CG) groups. The individuals of the WBVeG performed 10 sessions of WBVe in an oscillating/vibratory platform (OVP), barefoot, for 3 minutes at the peak-to-peak displacements of 2.5, 5.0, and 7.5 mm, with a resting period of 1 minute (total time: 18 minutes/session). The frequencies ranged from 5 up to 14 Hz. The individuals of the CG performed all the steps of the study, but the OVP was turned off. Before the first and after the tenth session, the individuals performed the SPPB. Significant responses were found in the WBVeG, analyzing the total score of the SPPB (P = .005), the balance test (P = .01), the gait speed (P = .006), and the 5CS test (P = .03), resulting in the improvement of the functionality of individuals with MetS.