Effects of Resistance-based Exercise Snacks With Varying Fragmentation Patterns on Lower Limb Function and Executive Cognition in Pre-frail Older Adults

This four-arm randomized pilot trial (N=48-60) compares four fragmentation patterns of a three-exercise resistance snack (sit-to-stand, squat, heel raise; 15 repetitions/exercise/day) in pre-frail older adults (Fried score 1-2, ≥70 years). Groups differ by repetitions/bout×bouts/day: G1=1×15, G2=3×5, G3=5×3, G4=15×1. Outcomes (lower limb strength, balance, executive function) are assessed at baseline, week 4, and week 8. The study will determine the optimal fragmentation pattern and provide effect sizes for a future definitive trial.

Study Overview

• Status: Not yet recruiting
• Conditions: Effects of Exercise on Older Adults
• Intervention / Treatment: Behavioral: Highly Fragmented Exercise Snack; Behavioral: Moderately Fragmented Exercise Snack; Behavioral: Lowly Fragmented Exercise Snack; Behavioral: Consecutive Exercise (Active Control)

Detailed Description

This is a four-arm, parallel-group, randomized controlled pilot trial. Forty-eight to sixty community-dwelling pre-frail older adults (Fried frailty phenotype score 1-2, aged ≥70 years) will be randomly assigned to one of four groups (1:1:1:1 ratio). All groups perform a fixed total daily volume of 15 repetitions per exercise (sit-to-stand, squat, and heel raise), resulting in 45 total repetitions per day. The only difference between groups is the fragmentation pattern (i.e., repetitions per bout × bouts per day):

G1 (highly fragmented): 1 repetition of each exercise per bout, 15 bouts/day (~30 seconds per bout)

G2 (moderately fragmented): 3 repetitions of each exercise per bout, 5 bouts/day (~90 seconds per bout)

G3 (lowly fragmented): 5 repetitions of each exercise per bout, 3 bouts/day (~2.5 minutes per bout)

G4 (consecutive control): 15 repetitions of each exercise per bout, 1 bout/day (~7.5 minutes per bout)

The intervention period is 8 weeks. Outcomes are assessed at baseline, mid-intervention (week 4), and post-intervention (week 8). Primary outcomes include lower limb strength (30-second chair stand test) and dynamic balance (Timed Up and Go test). Secondary outcomes include comprehensive physical function (Short Physical Performance Battery), executive function (Stroop Color-Word Test and Trail Making Test), falls efficacy (modified Falls Efficacy Scale), adherence, acceptability, and adverse events.

• Study Type: Interventional
• Enrollment (Estimated): 60
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: yongzhao fan, PHD; Phone Number: China：13051065318; Email: fanyongzhao@cupes.edu.cn

Study Locations

• China
  • Beijing, China
    • Capital University of Physical Education and Sports, Beijing
    • Contact: yongzhao fan, PHD; Phone Number: China：13051065318; Email: fanyongzhao@cupes.edu.cn

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• 1. Age 65 years or older 2. Community-dwelling (living independently, not in a nursing home or long-term care facility) 3. Pre-frail status confirmed by Fried Frailty Phenotype score of 1-2 4. Mini-Mental State Examination (MMSE) score ≥24 5. Able to walk independently with or without a cane 6. No regular lower limb strength training (less than 2 times per week) in the past 3 months 7. Willing to adhere to the 8-week exercise intervention and complete all assessments 8. Provide written informed consent before any study-related procedures

Exclusion Criteria:

• 1. Lower limb fracture or joint replacement surgery within the past 6 months 2. Unstable angina or uncontrolled hypertension (resting systolic blood pressure ≥160 mmHg) 3. Severe osteoporosis (T-score <-2.5 with history of fragility fracture) 4. Neurological disorders affecting motor function (e.g., Parkinson's disease, post-stroke hemiplegia) 5. Severe cognitive impairment (MMSE score <24) 6. Unstable cardiac or pulmonary disease (e.g., recent myocardial infarction, severe COPD exacerbation) 7. Severe visual or hearing impairment that limits ability to follow instructions or perform exercises safely 8. Participation in another interventional clinical trial within the past 30 days 9. Any other medical or psychological condition that, in the opinion of the principal investigator, would compromise participant safety or study adherence

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

4

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Arm 1：Highly Fragmented Exercise Snack Group; Arm 1：Participants perform 1 repetition of each exercise (sit-to-stand, squat, and heel raise) per bout, 15 bouts per day, for 8 weeks. Each bout takes approximately 30 seconds.	Behavioral: Highly Fragmented Exercise Snack; Participants in Arm 1 perform a resistance-based exercise snack consisting of three exercises: sit-to-stand, squat, and heel raise. Each bout contains 1 repetition of each exercise (1-1-1 structure). Participants complete 15 bouts per day, with each bout taking approximately 30 seconds. The total daily volume is 15 repetitions per exercise (45 total repetitions). The intervention period is 8 weeks. Participants are instructed to use event-based triggers (e.g., after each bathroom visit or after drinking water) to initiate each bout. A demonstration video and a daily exercise log are provided.; Other Names: Arm 1
Experimental: Arm 2：Moderately Fragmented Exercise Snack Group; Arm 2：Participants perform 3 repetitions of each exercise (sit-to-stand, squat, and heel raise) per bout, 5 bouts per day, for 8 weeks. Each bout takes approximately 90 seconds.	Behavioral: Moderately Fragmented Exercise Snack; Participants in Arm 2 perform a resistance-based exercise snack consisting of three exercises: sit-to-stand, squat, and heel raise. Each bout contains 3 repetitions of each exercise (3-3-3 structure). Participants complete 5 bouts per day, with each bout taking approximately 90 seconds. The total daily volume is 15 repetitions per exercise (45 total repetitions). The intervention period is 8 weeks. Participants are instructed to perform bouts at fixed time points (e.g., morning, mid-morning, noon, afternoon, evening). A demonstration video and a daily exercise log are provided.; Other Names: Arm 2
Experimental: Arm 3：Lowly Fragmented Exercise Snack Group; Arm 3：Participants perform 5 repetitions of each exercise (sit-to-stand, squat, and heel raise) per bout, 3 bouts per day, for 8 weeks. Each bout takes approximately 2.5 minutes.	Behavioral: Lowly Fragmented Exercise Snack; Participants in Arm 3 perform a resistance-based exercise snack consisting of three exercises: sit-to-stand, squat, and heel raise. Each bout contains 5 repetitions of each exercise (5-5-5 structure). Participants complete 3 bouts per day, with each bout taking approximately 2.5 minutes. The total daily volume is 15 repetitions per exercise (45 total repetitions). The intervention period is 8 weeks. Participants are instructed to perform bouts at three fixed time points (e.g., morning, noon, evening). A demonstration video and a daily exercise log are provided.; Other Names: Arm 3
Experimental: Arm 4：Consecutive Control Group; Arm 4：Participants perform 15 repetitions of each exercise (sit-to-stand, squat, and heel raise) per bout, 1 bout per day, for 8 weeks. Each bout takes approximately 7.5 minutes.	Behavioral: Consecutive Exercise (Active Control); Participants in Arm 4 perform a resistance-based exercise session consisting of three exercises: sit-to-stand, squat, and heel raise. Each bout contains 15 repetitions of each exercise (15-15-15 structure). Participants complete 1 bout per day, with the bout taking approximately 7.5 minutes. The total daily volume is 15 repetitions per exercise (45 total repetitions). The intervention period is 8 weeks. Participants are instructed to perform the bout at a fixed time each day (e.g., 10:00 AM). A demonstration video and a daily exercise log are provided.; Other Names: Arm 4

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Lower Limb Muscle Strength	Measured by the 30-Second Chair Stand Test (30-CST). The number of times a participant can stand up from a sitting position and sit back down within 30 seconds. A higher score indicates better lower limb strength.	Baseline (Week 0), Mid-intervention (Week 4), Post-intervention (Week 8)
Dynamic Balance and Mobility	Measured by the Timed Up and Go (TUG) test. The time (in seconds) taken to stand up from a chair, walk 3 meters, turn around, walk back, and sit down. A shorter time indicates better dynamic balance and mobility.	Baseline (Week 0), Mid-intervention (Week 4), Post-intervention (Week 8)

Collaborators and Investigators

• Sponsor: Capital University of Physical Education and Sports, China
• Investigators: Study Director: yongzhao fan, Capital University of Physical Education And Sports

Publications and helpful links

Helpful Links

• Related Info

Study record dates

Study Major Dates

• Study Start (Estimated): May 1, 2026
• Primary Completion (Estimated): August 5, 2026
• Study Completion (Estimated): August 15, 2026

Study Registration Dates

• First Submitted: April 19, 2026
• First Submitted That Met QC Criteria: April 19, 2026
• First Posted (Actual): April 24, 2026

Study Record Updates

• Last Update Posted (Actual): April 24, 2026
• Last Update Submitted That Met QC Criteria: April 19, 2026
• Last Verified: April 1, 2026

More Information

Terms related to this study

• Keywords: Resistance training; Exercise snacks; Pre-frail older adults
• Additional Relevant MeSH Terms: DMAC2L protein, human
• Other Study ID Numbers: CUPES-PY-2026420

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: The individual participant data (IPD) from this study, including anonymized performance metrics, physiological responses, and metabolic data, will be shared with other researchers upon reasonable request. Data will be provided in accordance with applicable ethical and regulatory guidelines to ensure the privacy and confidentiality of study participants. Requests for data access can be made by contacting the principal investigator,Fanyongzhao, at fanyongzhao@cupes.edu.cn.
• IPD Sharing Time Frame: The IPD and supporting information will be made available starting from 6 months after the publication of the study results and will remain available for 5 years.
• IPD Sharing Access Criteria: The IPD and supporting information will be available to qualified researchers upon request. Access will be granted after a data-sharing agreement is signed to ensure the data will be used responsibly and in accordance with ethical guidelines. Researchers can request access by contacting the Principal Investigator at fanyongzhao@cupes.edu.cn.
• IPD Sharing Supporting Information Type: SAP

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No