Whole-Body Vibration Training

Effects on Balance, Lower Body Strength, Balance Confidence and

Health-related Quality of Lifein Older Adults

Lyndsay Foisey Western University, Ontario Canada

Introduction Methods Statistical Analysis Results Conclusion Limitations Recommendations for Future Trials

Overview

30% older adults 65 years + fall at least once per year ◦ Leading cause of disability, injury, death

Major cause of functional decline and increased dependency health care system usage

Poor muscle strength, poor balance, fear of falling common age-related factors associated with fall risk

Introduction

Balance and strength training programs decrease fear of falling, improve balance, strength

However, older adults may be unwilling/unable to exercise ◦ >50% not meeting current PA standards

New exercise method gaining popularity is whole-body vibration (WBV) training◦ Less time/effort than traditional exercise

Introduction (cont.)

What is Whole-Body Vibration (WBV) Training?

Typically consists of standing or exercising on vibrating platform for single or multiple sessions

Vibrations transmitted through lower body from the point of contact (i.e. the feet)

Vibration creates reflex muscle contraction which is theorized to be reason for strength improvements

Increased muscle activity compared to no vibration

Introduction (cont.)

Whole-Body Vibration training and Aging Research

Safe method of exercise for older adults Study durations of 6 weeks to 18 months Significant improvements in strength, balance Increased compliance to WBV program than Ex

program

No study on fear of falling and WBV Need for research on effective and efficient program Questions about tolerance of program; not many

studies in North America

Introduction (cont.)

Research Question

What are the effects of an 8-week whole-body vibration training

program on the balance, lower body strength, balance confidence and

quality of life in older adults?

N = 23 (12 WBV; 11 control), randomized Aged 62 – 92 years old WBV protocol

◦ 3 sessions per week (8 weeks)◦ 60 seconds on platform, rest, repeat; total time 6 to 11

minutes Measures conducted before and after 8 weeks:

1. Body Sway2. Lower Body Strength3. Functional Balance4. Balance Confidence5. Quality of Life

Methods

1. Body Sway (Balance)

◦ Specific balance measure that records spontaneous sway while standing on force platform (technical device to measure balance)

◦ Stood as still as possible, arms relaxed by side◦ Significant results reported in previous WBV

studies

Methods (cont.)

2. Sit-to-Stand Test (Lower Body Strength)

◦ From seated position with feet on floor, participant stood and returned to seated position 5 times as quick as possible. Time to complete 5 sit-to-stands recorded.

◦ Indirect measure of knee extension strength/power

◦ Fast, low cost equipment (chair, time watch)◦ Implemented in previous WBV study

Methods (cont.)

3. Activities-specific Balance Confidence scale (Balance Confidence)

◦ Fear of falling measure for community-dwelling older adults

◦ Completed a one-page survey◦ Participant rated their perceived balance

confidence from 0-100% on tasks such as stepping on escalator, standing on a chair

◦ Improved in previous physical activity studies

Methods (cont.)

4. Berg Balance Scale (Functional Balance)

◦ Participant asked to perform 14 balance tasks such as seat transfer, one-leg stance, pick up object from floor

◦ Rated from 0-4, to maximum of 56 points 0-20 total points indicates severe fall risk 21-40 Medium fall risk 41-56 Low fall risk

Methods (cont.)

5. Medical Outcome Survey Short-form 36 (Health-related Quality of Life)

◦ Participants completed survey of 36 questions◦ Evaluates levels from 0 to 100 for 4 phys health, 4

mental health areas◦ Improved in previous WBV study with long-term

care residents

Methods (cont.)

Two-way Analysis of Variance (ANOVA); Group and Time for Body Sway parameters

Wilcoxon Signed-Rank for within-subject analysis for Berg Balance Scale, Sit-to-Stand, Balance Confidence, Quality of Life

Mann Whitney for between-group analysis Berg Balance Scale, Sit-to-Stand, Balance Confidence, Quality of Life

Statistical Analysis

After 8 weeks:Results

Measure WBV Control

Body Sway No Change No Change

Lower Body Strength Significant Improvement

(p = 0.04)

No Change

Functional Balance Significant Improvement

(p = 0.04)

No Change

Balance Confidence No Change No Change

Quality of Life No Change No Change

Body Sway◦ No change after 8 weeks◦ No difference in body sway detected between

WBV group or control group

Results (cont.)

WBV group Control Group

Resultant Sway

Pre-test 8 weeks Pre-test 8 weeks

Medial-lateral sway range (mm)

33.85±10.19 31.89 ±7.78 35.90 ±9.27 43.37±19.06

Anterior-posterior sway range (mm)

22.31±23.85 14.94±6.17 22.64±18.17 18.80±5.98

Sit-to-Stand scores (Lower Body Strength)

Results (cont.)

Pre-test 8 weeks10

10.5

11

11.5

12

12.5

WBV

Control

Time

Tim

e in

Secon

ds

*

Berg Balance Scale scores (Functional Balance)

Results (cont.)

Pre-test 8 weeks3940414243444546474849

WBV

Control

Time

Score

/5

6

*

Activities-specific Balance Confidence Scale (Balance Confidence)

No change for either WBV or control after 8 week trial; however WBV slightly improved compared to control (ns)

Results (cont.)

Pre-test Week 880

81

82

83

84

85

86

87

WBVControl

Time

AB

C S

core

(/1

00

)

MOS Short-Form 36 (Health-related quality of life measure)

◦ No statistically significant difference for either group after 8 week trial

◦ Noteworthy: Physical Function for WBV (p = .059)

Results (cont.)

Take Home Message Functional balance and lower body strength

measures significantly improvement in the WBV group after 8 weeks

Balance confidence and quality of life ceiling effect?

All study participants found WBV program very tolerable

More research needed for optimal training prescription to improve balance, balance confidence

Conclusion

Small sample size◦ Results in low statistical power

Study duration ◦ To improve body sway, may need 1)to be longer

than 8 weeks, 2) to implement more difficult balance protocol during WBV training

Participants and researcher not blinded◦ Could create bias in test responses

Limitations

Implement balance protocol during WBV intervention

Larger sample size Participants with lower balance confidence

Recommendations for Future Trials