Effects of Whole-Body Vibration Combined With Foot Core Exercise Training on Muscle Strength, Balance, and Proprioception in Overweight and Obese Young Adults: A Randomized Controlled Single-Blind Trial
Overview
- Phase
- Not Applicable
- Status
- Completed
- Sponsor
- Istinye University
- Enrollment
- 26
- Locations
- 1
- Primary Endpoint
- Limits of Stability (composite score, %)
Overview
Brief Summary
This randomized, single-blind clinical trial investigates whether adding whole-body vibration (WBV) to a supervised foot core exercise program improves ankle muscle strength, balance, and proprioception in overweight and obese young adults (BMI 25.0-39.9 kg/m²). Participants attended 24 face-to-face sessions over 8 weeks (3×/week) under physiotherapist supervision. Outcomes included isometric inversion/eversion strength (hand-held dynamometry) and instrumented balance/proprioception tests (Limits of Stability, mCTSIB, single-leg balance, single-leg proprioception) recorded by a computerized balance analysis system.
Detailed Description
Design: randomized controlled, single-blind, parallel-group trial conducted at İstinye University Physiotherapy and Rehabilitation Practice & Research Center. Eligible adults (18-35 years; BMI 25-39.9 kg/m²) able to stand barefoot ≥15 s single-leg and perform 5 repetitions of 60° knee-flexion squats without rest were enrolled. Stratified randomization (sex, BMI) with computer sequence (Research Randomizer) and sealed opaque envelopes allocated participants to: (1) Exercise Group (EG): progressive foot core exercises performed on a vibration platform with vibration OFF; (2) WBV-Combined Exercise Group (TEG): identical exercises WITH synchronous whole-body vibration (20-50 Hz; 15-60 s bouts) using a DKN Technology Xg-10 Pro device. Both groups completed 24 supervised sessions across 8 weeks (3×/week). A standardized warm-up/self-massage of the foot/ankle preceded exercises; progression targeted repetitions, active time, and (in TEG) vibration frequency.
Assessments were performed pre- and post-intervention in fixed order with rest intervals. Ankle inversion/eversion strength was measured using a J-Tech Commander Echo digital handheld dynamometer (kg-force). Balance and proprioception were quantified on the PROKIN computerized system (Limits of Stability; mCTSIB; single-leg balance; single-leg proprioception metrics including trunk total standard deviation and mean tracking error).
Statistical plan: normality by Shapiro-Wilk; parametric tests for normally distributed variables (paired t-test within groups; independent t-test between groups), Mann-Whitney U for non-normal age, chi-square for categorical variables; Cohen's d for effect size where within-group change was significant. Analyses in IBM SPSS 25.0. Sample size was estimated a priori for large effect (d=0.8), α=0.05, power=0.80 (planned n=26; 13/group). Post-hoc power for Limits of Stability change in TEG yielded d=0.96, power=0.87. No funding; no conflicts declared.
Study Design
- Study Type
- Interventional
- Allocation
- Randomized
- Intervention Model
- Parallel
- Primary Purpose
- Treatment
- Masking
- Single (Participant)
Masking Description
Single (Participant). Masking was applied to participants; groups were scheduled to avoid contact.
Eligibility Criteria
- Ages
- 18 Years to 35 Years (Adult)
- Sex
- All
- Accepts Healthy Volunteers
- Yes
Inclusion Criteria
- •• Age 18-35 years; BMI 25.0-39.9 kg/m².
- •Ability to stand barefoot on a firm surface ≥15 seconds single-leg (one attempt).
- •Ability to perform 5 repetitions of 60° knee-flexion squat without needing rest.
- •Turkish language proficiency for written and verbal communication.
Exclusion Criteria
- •Any medical history requiring regular physician follow-up.
- •Musculoskeletal trauma within the past 12 months.
- •Use within 48 h of medications affecting musculoskeletal performance.
- •Prior surgery or residual deficits from previous trauma.
- •Pregnancy or suspected pregnancy.
- •Any reported contraindication to use of a vibration platform.
- •During study: pain \>3/10 on VAS; abnormal blood pressure responses during/after sessions; three consecutive absences; failure to meet progression criteria; incident illness/trauma; withdrawal request.
Arms & Interventions
Exercise Group (EG)
Progressive foot core exercise program performed on a vibration platform with vibration disabled; supervised 3×/week for 8 weeks (24 sessions). Standardized warm-up/self-massage, then sequence including foot tapping, bilateral heel raises, arch raises with toe ab/adduction, and single-leg stance on BOSU; progression by repetitions and active time.
Intervention: Supervised Foot Core Exercise Training (No Vibration) (Behavioral)
Exercise Group (EG)
Progressive foot core exercise program performed on a vibration platform with vibration disabled; supervised 3×/week for 8 weeks (24 sessions). Standardized warm-up/self-massage, then sequence including foot tapping, bilateral heel raises, arch raises with toe ab/adduction, and single-leg stance on BOSU; progression by repetitions and active time.
Intervention: Whole-Body Vibration via DKN Technology Xg-10 Pro (Device)
WBV-Combined Exercise Group (TEG)
Identical supervised foot core exercise program performed with whole-body vibration during exercises; same schedule (3×/week, 8 weeks).
Intervention: Whole-Body Vibration via DKN Technology Xg-10 Pro (Device)
Outcomes
Primary Outcomes
Limits of Stability (composite score, %)
Time Frame: Baseline to Week 8
Composite score from PROKIN computerized balance analysis system; higher scores reflect better voluntary control within stability boundaries; device-generated percentage scale. Safety Issue: No.
Secondary Outcomes
- Single-Leg Balance test (device score)(Baseline to Week 8)
- Modified Clinical Test of Sensory Interaction on Balance (mCTSIB)(Baseline to Week 8)
- Ankle Strength (kg-force)(Baseline to Week 8)
- Single-Leg Proprioception(Baseline to Week 8)
Investigators
Mirsad Alkan
asst. prof.
Istinye University