AgingNCT03888040
Fatigability of Lower Limb Muscle in Older Adults: Protective Effects of Strength Training Exercise in Old Men and Women
A study testing Exercise in people with Aging, run by Marquette University at 1 site in United States.
Trial summary
The proposed studies will assess 1) the mechanisms for the age-related increase in fatigability during dynamic exercise (Aims 1 and 2) and 2) the effectiveness of high-velocity resistance training coupled with blood flow restriction (BFR) in improving muscle power output and fatigability in older adults (Aim 3). Read more about this study
- Who is it for?
- Ages 18 to 100 yearsHealthy volunteers can take part
- Conditions the study is for
- Aging
- What is being tested?
- Exercise
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 22 participants
- Where
- 1 siteUnited States
- Study dates
- 1 Sep 2020to 31 Aug 2025
- Phase
- Interventional
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 100 years
- All sexes
- Healthy volunteers accepted
- Adult, Older adult
Who may be able to join
- men and women aged 18-40 years and >60 years
Who cannot join
- body mass index ≥40 kg/m2;
- type 1 or type 2 diabetes;
- uncontrolled hypertension;
- active cancer, cancer in remission, or having received treatment for any form of cancer in the previous five years;
- coronary artery disease;
- cardiovascular disease (e.g., PAD, PVD);
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- abnormal and untreated thyroid function;
- chronic and/or regular nonsteroidal anti-inflammatory drugs (NSAID) consumption,
- tobacco use (includes smoking);
- any condition that presents a limitation to exercise (e.g., severe arthritis, COPD, neuromuscular disorder, moderate or severe cognitive impairment, Alzheimer's Disease, severe untreated sleep apnea).
- women who are pregnant or likely to be pregnant.
- Subjects will be excluded if they have joint pain in the exercising leg or arm. Medication use. Medications currently taken or in the previous year and known to influence muscle mass (e.g., glucocorticoids, testosterone) and cortical and neuromuscular excitability will be exclusionary, while medications that may be prevalent among older adults (e.g., statins) will be accounted for with a covariate statistical model.
Trial locations and contacts
1 site in 1 country.
About this study
Official title: Fatigability of Limb Muscle in Older Adults: Protective Effects of Exercise
The proposed studies will assess 1) the mechanisms for the age-related increase in fatigability during dynamic exercise (Aims 1 and 2) and 2) the effectiveness of high-velocity resistance training coupled with blood flow restriction (BFR) in improving muscle power output and fatigability in older adults (Aim 3). The first two aims are cross-sectional studies comparing young (18-35 years old) and older adults (≥60 yrs old) to test our central hypothesis that the greater accumulation of metabolites and increase in fatigability in older adults is due to either age-related impairments in skeletal muscle bioenergetics (Aim 1) and/or vascular dysfunction (Aim 2). These two aims will integrate techniques to assess whole-muscle bioenergetics (31P-MRS) and in vivo vascular function (near infrared spectroscopy; NIRS and doppler ultrasonography) with in vitro assessment of single fiber bioenergetics (epifluorescence microscopy) and vasoreactivity of isolated skeletal muscle arterioles (video microscopy). We will then determine whether bioenergetics, vascular function and fatigability are altered in older men and women in response to 8 weeks of resistance exercise training of the lower limb both with and without blood flow restriction (Aim 3).
- Conditions
- Aging
- Being tested
- Exercise
- Keywords
- Aging, Fatigue, Resistance training, Skeletal Muscle, Knee extensor muscles, limb power
- Medical subject headings
- Fatigue
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
ExerciseOther
The participant will attend 3 training sessions per week for 8 weeks. Resistance training will be performed by each leg with a load of 30% of maximal strength: one leg with and the other without blood flow restriction.
| Study group | Role | What they receive |
|---|---|---|
| Blood Flow Restriction Training | Experimental | This leg will perform low-load resistance training at 25% of the one-repetition maximum (1-RM) with blood flow restriction. While seated upright in a knee-extension machine, participants will complete two sets of 15 repetitions followed by a third set to volitional failure. All repetitions will be performed as quickly as possible, with 30 seconds of rest between sets. Receives: Other: Exercise |
| Resistance Training Only | Experimental | This leg will perform low-load resistance training at 25% of the one-repetition maximum (1-RM) without blood flow restriction. While seated upright in a knee-extension machine, participants will complete two sets of 15 repetitions followed by a third set matched to the number of repetitions completed by the BFR leg. All repetitions will be performed as quickly as possible, with 30 seconds of rest between sets. Receives: Other: Exercise |
What is being measured
The primary outcome is the main question the study is designed to answer.
Change in Fatigability of the Knee Extensor Muscles From Baseline to After 8 Weeks Training
For each leg, fatigability was measured at baseline and after 8 weeks as the percentage of muscle power lost during a 4-minute dynamic fatiguing exercise. At each assessment, fatigability was calculated as 100 × [(power output at the beginning of the exercise - power output at the end of the exercise) ÷ power output at the beginning of the exercise].
The reported outcome was calculated as baseline fatigability minus 8-week fatigability. For example, if fatigability was 32% at baseline and 16% at 8 weeks, the reported change was +16. This calculation represents the direct difference between the baseline and 8-week percentages, not a relative percent change from baseline. Positive values indicate less fatigability at 8 weeks, and negative values indicate greater fatigability at 8 weeks.
Measured: One session before and then after 8 weeks of training
Percent Change in Muscle Volume of the Quadricep Muscles Form Baseline to After 8 Weeks Training
Magnetic resonance imaging (MRI) was used to measure knee-extensor muscle volume before and after the intervention. The intervention-related change was expressed as a percentage of the pre-intervention volume. Positive values indicated an increase in muscle volume, whereas negative values indicated a decrease. For example, an increase from 1,000 to 1,100 cm³ would represent a 10% increase in muscle volume.
Measured: Before and after completion of resistance training intervention of 8 weeks.
Change in Vascular Function Via Flow-mediated Dilation of the Femoral Artery From Baseline to After 8 Weeks of Training
Leg macrovascular endothelial function was assessed using femoral artery flow-mediated dilation (FMD). Femoral artery diameter was measured by Doppler ultrasonography at rest. Blood flow to the lower limb was then temporarily occluded for 5 minutes using an inflated pressure cuff. After the cuff was released, the resulting increase in blood flow stimulated the artery to dilate, and its peak diameter was measured. FMD was calculated as the percentage increase from the resting diameter to the peak post-occlusion diameter. The intervention-related change in FMD was calculated as post-intervention FMD minus pre-intervention FMD and expressed in percentage points, with positive values indicating improved endothelial function. For example, an increase in FMD from 5% to 8% is a 3-percentage-point increase.
Measured: One session before and one after 8 weeks of training
Secondary outcomes (1)
Percent Change in Strength of the Quadricep Muscles Form Baseline to After 8 Weeks Training
Knee-extensor one-repetition maximum (1-RM) strength was assessed as the greatest load that each participant could successfully lift once through the full range of motion. The intervention-related change in strength was calculated as the percentage change in 1-RM from pre- to post-intervention, with positive values indicating an increase in strength.
Measured: One session before and after 8 weeks of training
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted25 Mar 2019
- Study start1 Sep 2020
- Primary completion7 Apr 2025
- Study completion31 Aug 2025
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Posted resultsParticipant flow, outcome measures and adverse events reported by the sponsor.
- Other trials for AgingStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Model description
- Exercise Training Intervention: The older adult subjects that were recruited for the cross-sectional studies will then be asked to return to perform 8 weeks of resistance exercise training on each leg. The exercise will involve low-load, high-velocity power training of the knee extensor muscles. One of the legs will be counterbalanced based on strength to either exercise with blood flow restriction (BFR), while the other leg will exercise without BFR. Before and after the 8 weeks of training subjects will undergo the same measurements in the cross-sectional studies to assess fatigability, skeletal muscle bioenergetics and vascular function of each leg.
- Masking
- None (open label)
- Enrolment
- 22 participants (actual)
Sponsor and investigators
- Lead sponsor
- Marquette University
- Sponsor type
- University, hospital or other
- Collaborators
- National Institute on Aging (NIA), Medical College of Wisconsin
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT03888040
- Sponsor's protocol ID
- HR-2945
- Other IDs
- R01AG048262
- Status last verified
- May 2025
- First submitted
- 14 Mar 2019
- Last updated
- 13 Oct 2026
- Results posted
- Yes, on ClinicalTrials.gov
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No