Effects of whole-body vibration on heart rate variability: acute responses and training adaptations

Vibrational exercise for Crohn's to observe response (VECTOR): Protocol for a randomized controlled trial

Crohn's disease (CD) is a long-term inflammatory gastrointestinal disorder, often adversely affecting physical, emotional, and psychological well-being. Pharmaceutical management is habitually adopted; although medicinal therapies require continuous administration, and are often associated with significant side effects and low adherence rates. Whole body vibration (WBV) represents a non-invasive technique, that provides vibration stimulation to the entire body. As WBV appears to target the physiological pathways and symptoms pertinent to CD epidemiology, it may have significant potential as a novel non-pharmaceutical intervention therapy in CD. This paper presents the study protocol for a randomised controlled trial investigating the impact of WBV on health outcomes in individuals with CD. This 6-week, parallel randomised controlled trial will recruit 168 individuals, assigned to receive WBV and lifestyle education 3 times per week compared to control, receiving lifestyle education only. The primary outcome of the trial will be the difference from baseline to post-intervention in health-related quality of life between the groups, assessed with the Inflammatory Bowel Disease Quality of Life Questionnaire. Secondary outcomes will include between-group differences in other questionnaires assessing fatigue, anxiety and pain, measures of physical fitness, and biological markers for disease activity and inflammation. Statistical analyses will follow an intention-to-treat approach, using linear mixed-effects models to compare changes between time points and both trial groups. Ethical approval was granted by the Nottingham Research Ethics Committee (REC: 24/EM/0106) and the study has been registered prospectively as a clinical trial (NTC06211400).

Modification of heart rate variability induced by focal muscle vibration in patients with severe acquired brain injury

BACKGROUND/PURPOSE

Heart rate variability (HRV) is a biomarker of autonomic nervous system (ANS) reaction in persons with severe acquired brain injury (sABI) who undergo a rehabilitation treatment, such as focal muscle vibration (FMV).This study aims to evaluate if and how FMV can modulate HRV and to compare potential differences in FMV modulation in HRV between patients with sABI and healthy controls.

METHODS

Ten patients with sABI and seven healthy controls have been recruited. Each individual underwent the same stimulation protocol (four consecutive trains of vibration of 5 minutes each with a 1-minute pause). HRV was analyzed through the ratio of frequency domain heart-rate variability (LF/HF).

RESULTS

In the control group, after performing FMV, a significant LF/HF difference was observed in the in the second vibration session compared to the POST phase. Patients with SABI treated on the affected side showed a statistically significant LF/HF difference in the PRE compared to the first vibration session.

CONCLUSION

These preliminary results suggest that FMV may modify the cardiac ANS activity in patients with sABI.

Protocol for a Pilot Study on the Neurocardiac Mechanism of an Interoceptive Compassion-Based Heart-Smile Training for Depression

Background

Heart-Smile Training (HST) is an interoceptive compassion-based behavioral intervention that in case reports has been beneficial for depression. Interoception refers to the awareness and regulation of physiological signals from inside the body. Depressed patients often have diminished interoceptive awareness and often experience disconnection from bodily needs and sensations. In addition to interoceptive dysfunction, depression often involves negative self-evaluation and self-critical rumination. HST is a compassion-based meditation training program that explicitly cultivates interoceptive awareness of the heart area. This study aims to investigate the possible neurocardiac mechanisms engaged through HST for depression patients.

Methods

We plan to enroll 50 subjects to be randomized into a 4-week HST intervention group and a waitlist group. A battery of psychological questionnaires will be administered at baseline and post-intervention timepoints, and electroencephalography (EEG) will be collected during compassion meditation guided by pre-recorded audio. The primary clinical outcome measures are on the feasibility of the intervention and research procedures, the primary mechanistic outcome measure is the post-intervention change in Heartbeat Evoked Potential (HEP) amplitude. Secondary outcome measures include changes in depression severity and EEG gamma spectral activity. Exploratory outcome measures include effects of HST on skin conductance response, heart rate variability, EEG spectral properties in other frequency bands, as well as a list of psychological questionnaires that measure depression and anxiety symptoms, emotion regulation, mindfulness, interoceptive awareness, self-compassion, gratitude, sleep quality, quality of life and social connectedness.

Results

Results not yet available.

Conclusion

This is the first study on the feasibility and interoceptive neurocardiac mechanism of HST. Our findings will provide frontier knowledge on the physiological working mechanism of behavioral interventions with an interoception-based meditative approach. https://clinicaltrials.gov/study/NCT05564533.

Alterations of Body Composition, Blood Morphology and Fibrinogen Concentration after Vibration Therapy in Older Adult Women: A Randomized Controlled Trial

Vibrotherapy is one of the methods of physical therapy. Vibration, like various forms of physical activity, affects metabolic processes and health. The aim of this study was to assess the influence of thirty vibration sessions on body composition, hematologic and rheological indexes of blood, and protein and fibrinogen concentration in elderly women's blood. The study included 69 women, aged 60-70 years (mean age 64.6 ± 2.9), who were randomly and parallel assigned into: the vibrotherapy group 1 (G1) that took part in vibrotherapy on the Knees module, the vibrotherapy group 2 (G2) that took part in vibrotherapy on the Metabolism module, and the control group (CG) without interventions. In all patients, the following assessments were performed twice-baseline and after thirty vibrotherapy sessions: an assessment of body composition, a complete blood count with a hematology analyzer and erythrocyte aggregation by a laser-optical rotational red cell analyzer; total plasma protein and fibrinogen concentrations were established, respectively, by biuret and spectrophotometric methods. Intergroup (between groups) and intragroup (within each group) changes were statistically evaluated. After applying thirty vibration sessions, a decrease in body composition parameters (BM, body mass G1, p < 0.05; G2, p < 0.001 and FFM, fat free mass G1, p < 0.05; G2, p < 0.05) was confirmed in both intervention groups and BMI, body mass index in G2 (p < 0.05). It was found that, in G2, changes in erythrocyte aggregation indexes (T ½, half time kinetics of aggregation, p < 0.05 and AI, aggregation index, p < 0.05) and decrease of fibrinogen concentration (p < 0.05) took place. A series of thirty vibration sessions did not cause significant alterations in blood morphological parameters; therefore, vibrotherapy did not disturb hematological balance. Vibration sessions had a positive effect on BM, BMI, AG and fibrinogen concentration in the studied women, indicating the usefulness of this form of activation in older adults. Due to a decrease in FFM observed in the study, vibrotherapy should be employed in conjunction with physical exercise and other forms of physical activity in the group of older adults.

Combined effects of whole-body vibration and dynamic squats on cardiovascular and salivary biomarker responses in healthy adults

This study aimed to investigate the acute effects of combining whole-body vibration with dynamic squats on cardiovascular and salivary bio-marker responses in healthy adults. A randomized crossover design was conducted with 20 healthy adults. Each participant underwent three exercise sessions, with a 2-week washout period between each session. The sessions consisted of: (1) whole-body vibration (VB) at 25 Hz for 2 minutes, with an amplitude of 2 mm, and 2 minutes of rest between sets, for a total of 5 sets; (2) dynamic squats (SQ) performed 15 times within 2 minutes, with a 2-minute rest between sets, for a total of 5 sets; and (3) a combination of whole-body VB and SQ (VB+SQ). The cardiovascular variables and salivary biomarkers related to exercise intensity were assessed. Only the VB+SQ session significantly decreased the unstimulated salivary flow rate, and caused greater changes in heart rate, systolic blood pressure, mean arterial pressure, rate-pressure product, and heart rate variability compared to VB or SQ alone. Moreover, the VB+SQ session significantly increased the salivary total protein concentration from 0.56±0.05 mg/mL (baseline) to 0.74± 0.06 mg/mL (postexercise condition) and the salivary alpha-amylase activity from 33.83±5.56 U/mL (baseline) to 63.63±12.33 U/mL (postexercise condition) (P<0.05). These changes were recovered at 1-hr postexercise condition. Our findings provide information for designing exercise programs that incorporate VB+SQ to enhance hemodynamic and cardiac autonomic responses in healthy adults and for application during rehabilitation periods.

Sound stimulation using the individual's heart rate to improve the stability and homeostasis of the autonomic nervous system

OBJECTIVES

In this study, we explain the role of enhancing the stability and homeostasis of the autonomic nervous system (ANS) by proposing the average heart rate sound resonance (aHRSR), a sound stimulation to prevent imbalance of ANS due to dynamic movement. The effect of aHRSR on ANS was analyzed through the time and frequency domain of heart rate variability (HRV) using the photoplethysmogram data (PPG) of 22 participants (DUIRB-202109-12).

METHOD

When the subjects performed dynamic movements that could cause changes in the ANS, HRV indicators using PPG data for 5 min before and after the movements were analyzed according to the presence or absence of aHRSR. The standard deviation of the NN intervals (SDNN), the square root of the mean squared differences of the NN intervals (RMSSD), low-frequency band (LF), and high-frequency band (HF), which represent sympathetic and parasympathetic nerve activity, were used as indicators, where SNDD and LF represent total ANS and sympathetic activity, while RMSSD and HF represent parasympathetic activity.

RESULTS

As the effects of aHRSR on dynamic movement, the recovery time of RR interval was advanced by about 15 s, SDNN increased from ([44.16 ± 13.11] to [47.85 ± 15.16]) ms, and RMSSD increased from ([23.73 ± 9.95] to [31.89 ± 12.48]) ms (p < 0.05), increasing the stability of the ANS and reducing instability. The effect of homeostasis of the ANS according to aHRSR is also shown in reducing the change rate of LF from (-13.83 to -8.83) %, and the rate of change of HF from (10.59 to 3.27) %.

CONCLUSIONS

These results suggest that aHRSR can affect the cardiovascular system by assisting physiological movements that occur during dynamic movement.

A Pre-Post Study on the Cardiorespiratory Response to Different Protocols of Exposure on a Vibratory Platform in Young Healthy Individuals

This study aimed to investigate the acute specific physiological effects of 15 min of whole-body vibration (WBV) exposure at six different types of vibrations on cardiorespiratory function in 26 healthy young subjects (sex ratio, 1:1; mean age, 20.73 years). The protocols included six variants of a combination of mechanical stimuli with different frequencies (15, 25, and 35 Hz) and direction of stimuli (vertical or diagonal). The investigated cardiorespiratory parameters were heart rate (HR), arterial oxygen saturation (SaO₂), respiratory rate (RR), and spirometric indicators: tidal volume (TV), vital capacity (VC), forced vital capacity (FVC), forced expiratory volume at 1 s (FEV₁), and maximum voluntary ventilation for 12 s (MVV). The data series were statistically processed by using descriptive and inferential statistical methods: the Shapiro–Wilk test, the two-way ANOVA with repeated measures, and post hoc analysis. We obtained significantly higher values for HR, TV, VC, FVC, FEV₁, and MVV after the WBV exposure. These parameters are significantly influenced by both the frequency and direction of stimuli, and certain protocols of WBV are noticeable for their distinct effects. Our results offer a new perspective on the possibility of using preferential variants of vibratory stimulation to obtain maximum cardiorespiratory physiological effects.

Effect of whole-body vibration after a resistance exercise bout on heart rate variability in hypertensive population

OBJECTIVES

To investigate the effect of whole-body vibration (WBV) in the recovery phase after resistance exercise (RE) bout on heart rate variability (HRV) and blood pressure (BP) in a hypertensive population.

METHODS

Twenty hypertensive males and females were randomly allocated into group A (RE bout), and group B (RE bout with WBV). Pre-test and post-test measure of HRV, systolic blood pressure, and diastolic blood pressure were taken before and after RE and placebo WBV in one group and in another group of RE with WBV in the recovery phase.

RESULTS

There were no significant differences in both RE bout group and RE bout with WBV on HRV parameters but on BP it has shown significant improvement in both groups with a p value of SBP and DBP as 0.001 and 0.03 respectively but comparatively RE with WBV in recovery has greater improvement.

CONCLUSIONS

Our data demonstrated that RE bout using WBV has no improvement on HRV but it has significantly improved BP in hypertensive population.

Acute Effects of Whole-Body Vibration on Peripheral Blood Flow, Vibrotactile Perception and Balance in Older Adults

Background: Non-invasive application of whole-body vibration (WBV) has the potential for inducing improvements in impaired peripheral circulation, cutaneous sensation and balance among older adults. However, relevant studies have frequently applied high magnitudes of vibration and show conflicting and inconclusive results. Therefore, we attempted to ascertain the acute responses in those parameters from exposure of thirty older subjects to WBV of three different magnitudes, defined according to ISO 2631-1 (1997). Methods: Each subject randomly underwent four sessions of intervention (three bouts of 1 min exposure with 1 min between-bout rests): WBV at 15, 20, or 25 Hz with a peak-to-peak displacement of 4 mm, or control condition. Results: Both during and after intervention, dorsal foot skin blood flow increased significantly under 20 and 25 Hz exposure conditions with greater responses under the latter condition, the magnitude of which slightly exceeded the recommended value. Plantar vibrotactile perception showed significant increases after WBV exposure with overall greater responses under higher frequencies of vibration. In contrast, no WBV-induced change in balance was observed. Conclusions: WBV at 20 Hz with a magnitude within the recommended limit can be effective in inducing enhancements in peripheral blood flow; however, the same magnitude of vibration seems insufficient in improving balance among older adults.

Whole-body vibration in the reduction of the cellulite

OBJECTIVE

Evaluate the effects of the whole body vibration in improving of cellulite in the women's gluteal region.

METHODS

Controlled clinical trial performed with 42 women, with cellulite in the gluteal region, detected by means of clinical examination. After evaluation, the women were divided into two groups: Whole-Body Vibration (WBV_G) and control (C_G). The evaluations were performed at the beginning and the end of 10 sessions and superficial skin temperature, perimetry in the gluteal region, analysis of body contouring, analysis of improvement by blind reviewers and instrument of satisfaction, by numeric scale were investigated.

RESULTS

In the thermographic analysis, the WBV_G obtained significant increase of superficial skin temperature on the right (p = 0.02) and left (p = 0.02) gluteal region. There was no difference in intra- and intergroups in perimetry and the analysis of body contour. The WBV_G obtained a higher percentage of improvement by assessment of the blind reviewers (p = 0.003) and greater aesthetics satisfaction (p = 0.006), when compared to C_G.

CONCLUSION

WBV provided an improvement in the aspect of the cellulite when assessed by blind reviewers and greater participants' satisfaction, providing a significant increase in the superficial skin temperature in the gluteal region.

Health effects associated with occupational exposure to hand-arm or whole body vibration

Workers in a number of different occupational sectors are exposed to workplace vibration on a daily basis. This exposure may arise through the use of powered-hand tools or hand-transmitted vibration (HTV). Workers might also be exposed to whole body vibration (WBV) by driving delivery vehicles, earth moving equipment, or through use of tools that generate vibration at low dominant frequencies and high amplitudes, such as jackhammers. Occupational exposure to vibration has been associated with an increased risk of musculoskeletal pain in the back, neck, hands, shoulders, and hips. Occupational exposure may also contribute to the development of peripheral and cardiovascular disorders and gastrointestinal problems. In addition, there are more recent data suggesting that occupational exposure to vibration may enhance the risk of developing certain cancers. The aim of this review is to provide an assessment of the occupations where exposure to vibration is most prevalent, and a description of the adverse health effects associated with occupational exposure to vibration. This review will examine (1) various experimental methods used to measure and describe the characteristics of vibration generated by various tools and vehicles, (2) the etiology of vibration-induced disorders, and (3) how these data were employed to assess and improve intervention strategies and equipment that reduces the transmission of vibration to the body. Finally, there is a discussion of the research gaps that need to be investigated to further reduction in the incidence of vibration-induced illnesses and injuries.