Old Age, Sarcopenia, Seniors
Conditions
Keywords
mobility, aging, balance, exercise, muscle
Brief summary
The goal of this clinical trial is to determine the effect of maximal mental effort combined with low-intensity resistance training on strength and neuromuscular function in older adults. The main questions it aims to answer are: * Does low-intensity resistance training in combination with maximal mental effort increase strength more than low intensity resistance training alone? * Does low-intensity resistance training in combination with maximal mental effort improve neuromuscular function more than low intensity resistance training alone? Participants will be randomly assigned to 1 of 3 groups: * Low intensity resistance training * Low intensity resistance training with maximal mental effort * Control Researchers will compare groups to determine differences in changes in strength, neuromuscular function, and body composition.
Detailed description
Participants in both training groups will perform 8 weeks of low intensity, whole-body resistance training. Participants in the control group will participate in all testing procedures but not perform any training. Participants from all groups will be instructed to otherwise maintain their normal physical activity levels and dietary habits. All training sessions will be supervised by research personnel at a Kennesaw State University fitness center. Participants will complete 2 training sessions per week for 8 weeks. Each training session will last about 45-60 minutes and consist of 5 exercises, including both multi-joint (leg press, chest press, back row) and single-joint (knee extension, bicep curl) exercises. Participants will perform 2 sets of 15 repetitions for each exercise for the first 2 weeks, then volume will be increased by progressing to 3 sets for the remaining 6 weeks. There will be a 60-second rest interval between sets and a similar tempo will be used between groups. Both training groups will perform the same training protocol, but participants in the maximal mental effort group will mentally urge their muscles to contract maximally during each repetition. That is, despite using a low intensity, participants will imagine the feeling of maximal muscle contraction of the primary muscles during each repetition. Several measures of strength, neuromuscular function, physical function, and body composition will be measured before and after the training or control period.
Interventions
BEHAVIORALLow Intensity Resistance Training with Maximal Mental Effort
This training intervention will be 8 weeks of low intensity resistance training, including whole-body and isolated muscle exercises, where participants will perform maximal mental effort by imagining maximal muscle contraction during each exercise.
BEHAVIORALLow Intensity Resistance Training
This training intervention will be 8 weeks of low intensity resistance training, including whole-body and isolated muscle exercises.
Sponsors
Kennesaw State University
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
OTHER
Masking
SINGLE (Subject)
Masking description
The mental effort aspect of the study will be concealed from subjects, so they will not be aware of any difference between training groups.
Intervention model description
Two intervention groups will perform different types of low intensity resistance training, and a control group will not perform any resistance training.
Eligibility
Sex/Gender
ALL
Age
65 Years to 85 Years
Healthy volunteers
Yes
Inclusion criteria
* Body mass index between 18.5 - 33 kg·m2 * No structured physical activity in past 2 years * Any unstable condition contradicting exercise * Independently walk with or without assistive device * No significant cognitive impairment
Exclusion criteria
* Score of 22 or lower on Montreal Cognitive Assessment * Missing more than 3 training sessions (training groups only) * Pacemaker * Unstable angina * Symptomatic heart failure * Uncontrolled arrythmias * Uncontrolled hypertension (greater or equal to 160/90) * Myocardial infarction in the past 6 months * Uncontrolled type 2 diabetes * Type 1 diabetes * Severe or unstable pulmonary conditions, * Currently on supplemental oxygen therapy * Severe hearing loss or visual impairment * Alzheimer's Disease or significant cognitive impairment * Stroke in the past 6 months or ongoing stroke-induced motor impairment * Any neurological (e.g., Parkinson's) condition affecting motor control * Undergoing chemotherapy * Surgery in past 6 months * Musculoskeletal injury in the past 6 months * Terminal illness * Stage 3 or greater chronic kidney disease
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in isokinetic strength of the knee extensors at 60 degrees per second | Baseline, Week 8 | Dynamic strength of the knee extensors contracting at a constant velocity |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change in isokinetic knee extensor muscle activation as measured by electromyography amplitude | Baseline, Week 8 | Electromyography root mean square during isokinetic contraction divided by root mean square during isometric contraction |
| Change in isometric knee extensor strength as measured by newton-meters of torque | Baseline, Week 8 | Isometric strength of a muscle |
| Change in knee extensor muscle activation as measured by electromyography amplitude | Baseline, Week 8 | A measure of the capacity at which the muscle is activated by the nervous system |
| Change in motor unit firing rate as measured relative to the motor unit recruitment threshold | Baseline, Week 8 | A measure of how nervous system input produces force output during an isometric contraction |
| Change in motor unit action potential size as measured relative to the motor unit recruitment threshold | Baseline, Week 8 | A measure of how nervous system input produces force output during an isometric contraction |
| Change in handgrip strength as measured in kilograms of force | Baseline, Week 8 | Upper-body strength as measured by a handgrip dynamometer |
| Change in walking speed as measured by time taken to walk 4 meters | Baseline, Week 8 | Measure of lower-body physical function |
| Change in chair rise performance as measured by number of chair rises performed in 30 seconds | Baseline, Week 8 | Measure of lower-body physical function |
| Change in bicep curl strength as measured by load lifted in pounds | Baseline, Week 8 | Maximum dumbbell load lifted successfully throughout the range of motion of a bicep curl |
| Change in dynamic strength of the lower body muscles during the leg press as measured by load lifted in pounds for 5 repetitions | Baseline, Week 5, Week 8 | Measure of dynamic strength during the leg press exercise |
| Change in muscle composition as measured by ultrasound-derived grey-scale analysis | Baseline, Week 8 | Echo-intensity value derived from grey-scale analysis is indicative of amount of non-contractile tissue in muscle |
| Change in skeletal muscle size as measured by ultrasound-derived cross-sectional area | Baseline, Week 8 | Size of a muscle |
| Change in fat mass as measured by kilograms | Baseline, Week 8 | Amount of fat tissue a person possesses estimated by bioelectrical impedance analysis |
| Change in fat-free mass as measured by kilograms | Baseline, Week 8 | Amount of non-fat tissue a person possesses estimated by bioelectrical impedance analysis |
| Change in body fat percentage as measured by fat tissue relative to fat-free tissue | Baseline, Week 8 | Relative amount of body fat a person possesses estimated by bioelectrical impedance analysis |
| Change in cognitive function as measured by the Montreal Cognitive Assessment | Baseline, Week 8 | Assessment of cognitive function where 0 is the lowest score and 30 is the highest score and a higher score represents higher cognitive function. |
Countries
United States
Contacts
CONTACTGarrett Hester Professor of Exercise Science
Outcome results
None listed