None listed
Conditions
Brief summary
Ageing is associated with reductions in muscle mass, muscle strength, and the ability to perform daily tasks (e.g., climbing the stairs), which can be accelerated during periods of short-term physical inactivity such as those imposed by periods of hospitalization, illness, or disease pandemics. There is a need, therefore, to identify effective strategies to counteract the negative effects of imposed physical inactivity on muscle mass and muscle strength. Resistance (strength) exercise can improve muscle mass and muscle strength in both younger and older adults, but participation rates are low, mainly due to barriers including a lack of time, the need for expensive equipment or a gym membership, and a high perception of difficulty. Recent evidence has shown that very brief (5-10 min) and frequent (twice per day) resistance exercise, requiring no equipment to perform, can improve muscle strength in older adults. This novel resistance exercise approach, termed "strength snacking", is therefore time-efficient, cost-effective, and simple – thereby avoiding the common barriers associated with traditional resistance exercise. "Strength snacking” may therefore be a feasible strategy for improving muscle function and health in older adults. It may also be a strategy to counteract the negative effects of short-term physical inactivity that occurs with by hospitalisation or illness, however, this has not yet been examined. The proposed study will be the first to determine whether "strength snacking” can offset the negative effects of short-term inactivity in older adults. It is hypothesised that "strength snacks” will be effective for offsetting anticipated muscle losses when performed during two weeks of imposed physical inactivity in older adults. We also expect that 4 weeks of "strength snacking" will be effective to improve muscle health and function.
Interventions
After one week of daily step count monitoring during their usual activities, participants will be randomly allocated to one of three study groups:
Group 1: Reduced steps
During the inactivity (step reduction) period, participants will be asked to reduce their daily step count by around 65% (to less than 1500 steps per day) compared to their normal daily values.
Participants will be asked to remain as inactive as possible during this period and engage in indoor activities at home requiring mi
After one week of daily step count monitoring during their usual activities, participants will be randomly allocated to one of three study groups: Group 1: Reduced steps During the inactivity (step reduction) period, participants will be asked to reduce their daily step count by around 65% (to less than 1500 steps per day) compared to their normal daily values. Participants will be asked to remain as inactive as possible during this period and engage in indoor activities at home requiring minimal physical activity (e.g., reading, watching television). As per the baseline period, the daily step counts of participants will be monitored using a pedometer worn on their wrist (which you will be asked to record in a logbook), and participant physical activity levels will also be measured using an ActivPAL accelerometer device. Group 2: Reduced steps plus "strength snacking” For participants allocated to the "strength snacking” group, "strength snacks” will be performed twice-daily (once in the morning, once in the evening) for 14 days during the reduced steps period. The "strength snacks” will consist of five bodyweight exercises (such as chair sit-to-stand, single-leg squats, calf raises, step-ups, standing balance, etc.) that will be standardised across all participants. Each exercise will be completed continuously for one minute, and participants will be asked to perform the maximum number of repetitions possible in one minute. One minute of rest will be allowed between each exercise. Each "strength snacking” session will therefore involve only 5 min of exercise (10 minutes total duration). The "strength snacking” intervention will be delivered to participants and monitored by the research team using a commercial smart device (phone/computer/tablet) application (Physitrack). Participants will receive the program via Physitrack, which will include videos of each exercise, and participants will be asked to record the completion of each exercise and note any relevants comments. Home-based exercise re-training program: After the 2-week reduced steps phase, participants in group 1 and 2 will be asked to resume their everyday and physical activity levels and ALL participants (in all 3 groups) will undertake a four-week, home-based exercise re-training program aimed at restoring (or improving) muscle mass and function. This program (including the exercises used and prescription used) will be delivered, performed, and monitored in an identical manner to the "strength snacking” intervention performed during the inactivity period, with the exception that it will be performed twice-daily on every second day for the four-week period. Retention and adherence: Retention will be recorded as the number (proportion) of participants that completed the 2-week step reduction intervention and the 4-week follow-up re-training program. Adherence to the exercise program, including the number of sessions completed, and the number of exercises, sets and repetitions completed within each session, will be recorded by participants using the Physitrack app. The exercise program will be considered feasible if at least 90% of participants complete the trial, and if adherence to the exercise program was at least 66%.
Sponsors
Deakin University
Study design
Allocation
Randomised controlled trial
Intervention model
Parallel
Primary purpose
Prevention
Masking
Open (masking not used)
Eligibility
Sex/Gender
All
Age
65 Years to 80 Years
Healthy volunteers
Yes
Inclusion criteria
Participants must be: 1) English-speaking, 2) non-smoking, 3) able to walk unaided or with minimal assistance for at least 50 m, 4) cognitively intact as indicated by a score of 2 or less on the Short Portable Mental Status Questionnaire (SPMSQ), and 5) identified as not being at a higher risk of an adverse event during exercise, as determined by the ESSA Adult Pre-exercise Screening System (APSS).
Exclusion criteria
Participants will be ineligible based on the following criteria: 1) participating in structured resistance training more than once per week in the previous three months, 2) acute or terminal illness likely to impact study involvement, 3) unstable or ongoing cardiovascular, metabolic, or respiratory disorders, 4) body mass index (BMI) less than 40 kg/m2, 5) current use of insulin or corticosteroids that could influence skeletal muscle metabolism, 6) musculoskeletal or neurological disorders impacting voluntary movement, 7) upper- or lower-extremity fracture in past three months, 8) presence of moderate-to-strong clinical risk factors (Anderson & Spencer, 2003) for deep vein thrombosis (DVT) (previous hip or knee replacement surgery, arthroscopic knee surgery, major general surgery in previous year, previous venous thromboembolism), or 9) current employment requiring regular standing and/or physical activity.
Outcome results
None listed