Muscle Function
Conditions
Keywords
Home-based exercise, Exercise snacking, Protein, Yogurt
Brief summary
Muscle size declines at around 0.5-1% per year after 50 years of age, with muscle strength declining up to twice as fast as muscle size. This may eventually lead to loss of independence if tasks of daily living become too strenuous to be performed safely. Exercise is recognized as a safe and effective means to counteract muscle loss during aging, however access to gym equipment may be logistically challenging or unpalatable to older adults. This research is designed to investigate the effect of 28 days of home-based leg exercise that doesn't require exercise equipment or supervision (exercise snacking), accompanied with a daily protein supplement in the form of commercially available yogurt, on the skeletal muscle health (i.e. function and size) of independent, community-dwelling older adults. To achieve this, two groups will be compared; one group will undertake exercise snacking and consume a 150 g yogurt with the breakfast meal for four weeks, with the second group only receiving the daily yogurt with no exercise snacking.
Detailed description
The study will require potential participants to undergo an eligibility screening with a member of the research team, followed by a period of seven days of habitual activity monitoring and 3 days of diet recording. Eligible participants will be allocated into study groups by way of minimization based on sex, age, BMI, and number of sit-to-stands performed in a minute. Participants will undertake two familiarisation sessions with strength, power, neural drive, and balance tests at least seven days apart, the first following eligibility screening and the second familiarisation session at least five days before the first main trial. Thereafter, both groups will undertake a main trial the day before commencing 28 days of daily 150 g yoghurt supplement with the breakfast meal, with the exercise snacking group (ES) also undertaking two bouts of exercise snacking a day. The main trial will include measures of leg muscle function and neural drive, standing and single leg balance, and movement co-ordination during tasks of everyday ambulation. Participants will wear a physical activity monitor and pedometer for the seven days and record diet for three days during the last week of the intervention. The day after the intervention period, a follow-up main trial will be conducted as per the first main trial, followed by an optional qualitative interview regarding participant's experience of the trial.
Interventions
BEHAVIORALExercise Snacking
Each bout of exercise snacking consists of 5 exercise. Each exercise is performed for one minute, with aim of completing as many repetitions as possible of that exercise in that minute. One minute of rest is observed between each exercise of the exercise snack. The five exercises are; sit-to-stand from a chair, marching on the spot, seated knee extensions alternating legs, standing knee bends alternating legs, and standing calf raises. The sit-to-stand exercise is always performed first, with the number of repetitions achieved recorded, and subsequent exercises performed in any order without recording of repetitions. Two exercise snacks are completed each day for 28 days; once in the morning and once in the evening, or at least separated by 2 hours.
DIETARY_SUPPLEMENTYogurt
Participants are asked to consume 150 g of yogurt (Arla, Skyr- natural flavour) with their breakfast meal. Participants may substitute the yogurt for another part of their regular breakfast, or add the yogurt to their regular breakfast, with participants asked to record a log book of daily yogurt consumption and to complete a three day food diary during the last week of the 28 day intervention period.
Sponsors
University of Bath
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
OTHER
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
65 Years to 80 Years
Healthy volunteers
Yes
Inclusion criteria
* Not underweight or obese (body mass index ≥20 and ≤ 30 kg/m2) * Not regularly engaging in recreational sports or structured exercise (once a week or more). * Non-smoker (for \>5 years) * Healthy (see
Exclusion criteria
)
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| 60 second sit to stand test | 28 days- change from pre- to post- intervention period | The participant is asked to stand up from sitting in a chair whilst keeping their arms folded across their chest, then return to the seated position as many times as possible in a minute. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Lower limb movement outcome variability | 28 days- change from pre- to post- intervention period | Measured during leg pressing |
| Lower limb muscle cross-sectional area | 28 days- change from pre- to post- intervention period | Measured using peripheral quantitative computed tomography at 66% distal calf length and 25% and 50% distal thigh length |
| Lower limb muscle cross-sectional tissue density | 28 days- change from pre- to post- intervention period | Measured using peripheral quantitative computed tomography at 66% distal calf length and 25% and 50% distal thigh length |
| Body composition | 28 days- change from pre- to post- intervention period | Measured using Dual Energy X-ray Absorptiometry |
| Gastrocnemius and quadriceps muscle fibre pennation angle | 28 days- change from pre- to post- intervention period | Measured using ultrasonography at 66% distal length of calf length and 50% distal thigh length |
| Lower limb muscle power | 28 days- change from pre- to post- intervention period | Measured during leg pressing |
| Postural sway during standing balance with eyes open and closed | 28 days- change from pre- to post- intervention period | Measured using a force plate |
| Single leg balance | 28 days- change from pre- to post- intervention period | Measured using the Y-balance test |
| Six minute walk test | 28 days- change from pre- to post- intervention period | The participant will be asked to walk as many times between two cones places 15 meters apart as possible in six minutes. |
| Movement co-ordination during walking and sit to stands | 28 days- change from pre- to post- intervention period | Measured by Qualisys motion capture and force plates |
| Central drive of the plantar flexors | 28 days- change from pre- to post- intervention period | Measured through the interpolated twitch technique |
| Gastrocnemius and quadriceps muscle fibre length | 28 days- change from pre- to post- intervention period | Measured using ultrasonography at 66% distal length of calf length and 50% distal thigh length |
Countries
United Kingdom
Outcome results
None listed