Accidental Falls, Aging, Postural Balance
Conditions
Keywords
Tai Chi, Tai Ji Quan, Mind-Body Exercise, Older Adults, Fall Prevention, Circadian Rhythm
Brief summary
This study investigates the effects of a 12-week Tai Chi intervention on balance function in community-dwelling older adults. Participants are randomly assigned to either a Tai Chi exercise group or a health education control group. The primary outcome is balance function measured by the Berg Balance Scale. Secondary outcomes include physical function, psychological well-being, cognitive function, and sleep quality. The study also explores the predictive and modifying roles of baseline circadian age on intervention outcomes.
Detailed description
BACKGROUND AND RATIONALE Falls are a leading cause of injury and disability in older adults, and balance dysfunction is a key modifiable risk factor. Tai Chi, a traditional Chinese mind-body exercise, has been shown to improve balance, reduce fall risk, and benefit cognitive health in older populations. However, individual variability in response to Tai Chi remains poorly understood, and the biological mechanisms underlying its benefits are incompletely characterized. Circadian rhythm disruption has emerged as a hallmark of biological aging. The investigators have developed and validated a circadian age (CircAge) assessment system based on the UK Biobank cohort (N\>90,000), which independently predicts mortality risk. Whether individuals with accelerated circadian aging benefit more from Tai Chi intervention is unknown. This trial addresses this gap by integrating circadian age assessment with multi-modal outcome evaluations. OBJECTIVES The primary objective is to evaluate the effect of a 12-week Tai Chi intervention on balance function in community-dwelling older adults. Secondary objectives are to assess effects on physical function, psychological health, cognitive function, and sleep quality. Exploratory objectives are to examine the predictive and modifying roles of baseline circadian age acceleration on intervention outcomes. STUDY DESIGN This is a two-arm parallel, single-blind (assessor-blinded) randomized controlled trial. Ninety community-dwelling older adults are randomly allocated 1:1 to a Tai Chi group or a health education control group. Randomization is computer-generated using variable block sizes, stratified by sex and baseline Berg Balance Scale score (≤45 vs \>45). Allocation concealment is maintained via sequentially numbered opaque sealed envelopes. Outcome assessors are blinded to group allocation. After the 12-week intervention, the control group is offered free Tai Chi classes to ensure ethical equipoise. ASSESSMENT SCHEDULE Wrist-worn accelerometer (ActiGraph) recordings are collected at baseline over 7 consecutive days for circadian age computation. All baseline accelerometer recordings are completed prior to randomization. Full outcome assessments are conducted at baseline (week 0) and at the end of intervention (week 12). A streamlined midpoint assessment (week 6) includes only the Berg Balance Scale and Timed Up and Go test. Fasting blood samples for routine clinical chemistry are collected at week 0 and week 12. STATISTICAL ANALYSIS A sample size of 90 (45 per group) provides \>80% power to detect a standardized effect size of d=0.50 in Berg Balance Scale change at week 12, assuming α=0.05 (two-sided) and 20% attrition. The primary analysis follows the intention-to-treat principle using linear mixed-effects models adjusted for baseline score, age, sex, and circadian age acceleration, with class as a random effect for the Tai Chi group. Exploratory analyses include circadian age × group interaction terms. LONG-TERM FOLLOW-UP After the 12-week intervention, participants are invited to enter a long-term health database with periodic follow-ups tracking balance function, fall events, and overall health status.
Interventions
BEHAVIORALTai Chi Exercise
Yang-style 24-form Tai Chi taught by a nationally certified master coach. Classes are offered five days per week, with participants required to attend at least three sessions per week, for a total of 12 weeks (target: ≥36 sessions). Each 60-minute session includes a 10-minute warm-up, 35 minutes of Tai Chi practice, 10 minutes of cool-down (including standing meditation and breathing exercises), and 5 minutes for questions and home practice reminders. Class size is limited to 10-15 participants.
BEHAVIORALHealth Education
Structured health education program delivered by professional medical and health management staff. Seminars cover topics including nutrition and dietary guidance, chronic disease management (hypertension, diabetes), fall prevention strategies, safe medication use, and general health literacy for older adults. The intervention runs for 12 weeks. Participants receive the same health screening, evaluation, and feedback benefits as the Tai Chi group. Free Tai Chi classes are offered to this group after the intervention period ends.
Sponsors
Zhide Liang
Macao Polytechnic University
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
SINGLE (Outcomes Assessor)
Masking description
Outcome assessors are blinded to group allocation. Assessors are not involved in randomization or intervention delivery. Assessments are conducted in a separate location from the intervention sessions. All participants wear standardized clothing and footwear during assessment to prevent inadvertent unblinding. Participants are reminded not to disclose their group assignment to assessors.
Intervention model description
Two-arm parallel randomized controlled trial. Participants are randomly assigned in a 1:1 ratio to either the Tai Chi intervention group or the health education control group. Both groups undergo the intervention concurrently for 12 weeks. After the intervention, the control group is offered free Tai Chi classes to ensure ethical equipoise.
Eligibility
Sex/Gender
ALL
Age
55 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
* Aged 55 years or older * Community-dwelling * Able to walk independently (assistive devices such as canes are permitted) * Berg Balance Scale (BBS) score ≤52 at screening * Able to understand and follow verbal instructions * Willing to wear a wrist accelerometer continuously for 7 days at baseline * Willing to accept random group assignment * Willing to undergo blood collection during the study * Provides written informed consent
Exclusion criteria
* Regular Tai Chi or yoga practice (more than once per week) within the past 6 months * Severe cognitive impairment (Montreal Cognitive Assessment \[MoCA\] score \<20 at screening, or previously diagnosed dementia) * Unstable cardiovascular disease (myocardial infarction, stroke, or hospitalization within the past 3 months) * Severe musculoskeletal disease that limits exercise participation * Neurological diseases affecting balance (e.g., Parkinson's disease, severe peripheral neuropathy) * Currently participating in another exercise intervention study * Planned surgery or extended absence during the study period * Contraindications to functional near-infrared spectroscopy (fNIRS) examination (e.g., scalp injury, metallic implants in the head region) * Severe psychiatric illness (e.g., schizophrenia, bipolar disorder) * Considered unable to safely participate in moderate-intensity physical activity as judged by the study physician or attending healthcare provider
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in Berg Balance Scale (BBS) Score | Change from baseline to end of intervention, up to 12 weeks | The Berg Balance Scale (BBS) is a 14-item performance-based measure of static and dynamic balance. Each item is scored 0-4 based on the participant's ability to perform tasks such as sitting to standing, transfers, standing unsupported with eyes closed, turning, and single-leg stance. Total scores range from 0 to 56, with higher scores indicating better balance function. Lower scores are associated with increased fall risk. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change in Timed Up and Go (TUG) Test | Change from baseline to end of intervention, up to 12 weeks | Functional mobility and dynamic balance test. Participants stand from an armed chair, walk 3 meters, turn, walk back, and sit down. Time to complete the task is recorded in seconds. Longer times indicate poorer mobility and higher fall risk. |
| Change in Grip Strength | Change from baseline to end of intervention, up to 12 weeks | Maximum grip strength measured using a handheld dynamometer, in kilograms. Three trials per hand; maximum value recorded. Higher values indicate greater muscle strength. Time Frame: Change from baseline to 12 weeks |
| Change in Balance Performance Measured by InBody Balance Trainer | Change from baseline to end of intervention, up to 12 weeks | Static balance assessed via center-of-pressure trajectory recorded by the InBody Balance Trainer during quiet standing, reported in millimeters. Shorter path length indicates better postural control. |
| Change in Single-Leg Eye-Closed Standing Time | Change from baseline to end of intervention, up to 12 weeks | Static balance is assessed by measuring the time (in seconds) participants can maintain single-leg standing with eyes closed. Both legs are tested. Longer times indicate better static balance and proprioception. |
| Change in Vertical Jump Height | Change from baseline to end of intervention, up to 12 weeks | Vertical jump test measures lower-extremity power and neuromuscular function. Participants perform three consecutive jumps, and the maximum jump height (in centimeters) is recorded. |
| Change in Reaction Time | Change from baseline to end of intervention, up to 12 weeks | Reaction time test measures central nervous system processing speed using a portable reaction time device. Faster reaction times are associated with lower fall risk and better cognitive processing. |
| Change in Activities-Specific Balance Confidence (ABC) Scale | Change from baseline to end of intervention, up to 12 weeks | The ABC Scale is a 16-item self-report measure of balance confidence during specific activities (e.g., walking, reaching, climbing stairs). Each item is rated 0-100%, with higher scores indicating greater balance confidence. |
| Change in Geriatric Depression Scale (GDS-15) Score | Change from baseline to end of intervention, up to 12 weeks | The 15-item Geriatric Depression Scale (GDS-15) screens for depressive symptoms in older adults. Total scores range from 0 to 15, with scores ≥5 suggesting depression. |
| Change in Generalized Anxiety Disorder Scale (GAD-7) Score | Change from baseline to end of intervention, up to 12 weeks | The 7-item Generalized Anxiety Disorder Scale (GAD-7) measures anxiety severity. Total scores range from 0 to 21, with scores ≥10 indicating moderate-to-severe anxiety. |
| Change in Shape Trail Test (STT) Part A and Part B Completion Time | Change from baseline to end of intervention, up to 12 weeks | The Shape Trail Test (STT) is a culturally adapted variant of the Trail Making Test developed for Chinese populations, avoiding reliance on the Latin alphabet. In Part A, participants connect numbered circles in sequence; in Part B, they alternate between circles and squares while ignoring the numbers. Completion time for each part is recorded in seconds, with longer times indicating poorer processing speed and executive function. STT-A and STT-B completion times are reported separately. |
| Change in Pittsburgh Sleep Quality Index (PSQI) Score | Change from baseline to end of intervention, up to 12 weeks | The Pittsburgh Sleep Quality Index (PSQI) is a 19-item self-report questionnaire assessing sleep quality over the past month. Total scores range from 0 to 21, with scores \>5 indicating poor sleep quality. |
Contacts
CONTACTZhide Liang, MS
STUDY_DIRECTORBaichao Xu, PhD
Hainan Medical College
STUDY_DIRECTORZiheng Ning, PhD
Macao Polytechnic University
Outcome results
None listed