Effects of Stochastic Whole-body Vibration Training on Balance and Executive Functions

University of Bern62 enrolled

Overview

Falls represent a significant financial burden, costing millions of dollars annually in Switzerland (SUVA, 2022). Good cognitive abilities and good balance represent modifiable protective factors against falls (Kurz, 2008). The present study investigates the impact of stochastic whole-body vibration training (SR-WBV) on executive functions and balance. To this end, participants were randomized into an intervention group or a control group. Participants in the intervention group underwent SR-WBV at a frequency of 5 Hertz (Hz), while participants in the control group underwent SR-WBV at 2 Hz. The training on an SRT Zeptor® Medical plus noise device consisted of three one-minute intervals of vibration, interspersed with one-minute rest periods. Data on executive functions (Updating, Shifting, Inhibition) and balance were collected before and after the intervention , complemented by subjective assessments of concentration and balance through questionnaires.

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

BASIC_SCIENCE

Masking

SINGLE

Enrollment

Conditions

Healthy

Interventions

Both the experimental group and the control group performed their training on an SRT Zeptor® Medical plus noise device (Frei Swiss AG, Zurich). The device featured two independent foot plates that vibrated stochastically in all three dimensions, resulting in multidimensional movement. During the training, participants were instructed to stand on the foot plates with both feet, keep their arms relaxed at their sides, maintain a slight bend in their knees, and focus their gaze on a fixation cross on the wall. Following the protocol used in Faes et al. (2018), each training session consisted of three series, each comprising one minute of vibration training followed by one minute of rest. The vibration frequency for the intervention group was set at 5 Hz.

2 Hz Stochastic Resonance Whole-Body Vibration TrainingOTHER

Eligibility

Sex: ALLMin age: 18 YearsHealthy volunteers:

Medical Language ↔ Plain English

Inclusion Criteria: * Healthy Exclusion Criteria: * Pregnancy * The presence of osteosynthetic materials (e.g., screws, plates, wires) * Joint problems (particularly in the knees, hips, and back) * Musculoskeletal issues * Disc herniation * Rheumatism * Cardiovascular problems * Balance disorders * Red-green color blindness * Intensive training within 24 hours prior to the assessment. * Use of central nervous system medications

Outcomes

Primary Outcomes

Sense of Balance (Change from Baseline)

Measured with subjective scale (sense of balance from 0 to 10) How do you assess your personal sensations regarding muscles and joints (back pain, shoulder and neck pain, leg muscle pain, etc.) at this moment? Please slide the scale for each aspect to the most appropriate level. 0 means no pain, and 10 means the most intense pain imaginable.

Time frame: 19 min before and 19 min after the intervention (immediate effects)

Balance (Change from Baseline)

Measured with the modified star excursion balance test (m-SEBT). Higher values indicate better balance with 0cm being the minimum and ca. 100cm indicating very good balance, i.e. reach distance. In this balance test, participants stand on one leg, while the range of motion of the other leg is measured in eight directions: anterior (ANT), posteromedial (PM), and posterolateral (PL). (Duration: 5 min)

Time frame: Immediately before and 13 min after the intervention (immediate effects)

Secondary Outcomes

Executive functions (Shifting) (Change from Baseline)

Measured with the Trail-Making Test B For TMT B, participants were presented with circles filled with both numbers and letters. They were required to click the circles in ascending order, alternating between numbers and letters (e.g., 1, A, 2, B, 3, C). The practice task consisted of six circles, and the main test involved 24 circles. The processing time was measured in milliseconds. Thus, higher scores in the Trail-Making Test B indicate lower shifting ability. (Duration: 3 min)

Time frame: 10 min before and 8 min after the intervention (immediate effects)

Executive functions (Updating) (Change from Baseline)

Measured with the Running Span-Task Participants were presented with a series of letters of varying lengths (3 to 8 letters). For each participant, both the total Running Span (sum of all correctly recalled target items) and the Running Span Score (sum of correctly recalled target items from sets that included at least one distractor) were calculated. Thus, higher scores (MIN = 0) in the Running Span-Task indicate higher updating ability. (Duration: 8 min)

Time frame: 18 min before and immediately after the intervention (immediate effects)

Executive functions (Inhibition) (Change from Baseline)

Measured with the Stroop Test in milliseconds (Reaction Time) The reaction times (in milliseconds) for all correctly identified incongruent items were subtracted from those for control items. 0 ms indicate no cognitive interference, i.e. maximal inhibitory control Thus, higher scores in the Stroop Test indicate higher cognitive interference, i.e. poorer inhibitory control (Duration: 2 min)

Time frame: 7 min before and 11 min after the intervention (immediate effects)