Sex-specific Adaptation to Resistance Training in Older Adults

Phase

N/A

Condition

N/A

Treatment

N/A

Clinical Study ID

NCT03440099

116-1974

1R01AG047245-01A1

Ages 65-75
All Genders
Accepts Healthy Volunteers

Study Summary

In general, men and women experience differing degrees of age-related decreases in physical function, with women having a greater prevalence of functional limitations and disability. A key predictor of this decrease in functional capacity is the reduction in leg muscle maximal power (product of force and velocity), which can be improved with exercise training. However, the development of exercise interventions to optimally improve skeletal muscle function in older adults has been difficult, in part because we now know that men and women respond differently to the same exercise training stimulus. In fact, the fundamental mechanisms by which habitual exercise improves physical function in older adults are still not well understood. The proposed studies are designed to address these knowledge gaps by examining the molecular and cellular mechanisms underlying the response to two distinct exercise training paradigms, and determining how these responses differ between older men and women. The investigators hypothesize that molecular, cellular and whole muscle contractile performance will be most improved in men by traditional low-velocity, high-load resistance training, and in women by high-velocity, low-load power training. Moreover, sex-specific structural responses in myofilament remodeling, protein expression and post-translational modifications will explain these sex-specific performance adaptations to each modality. To test these hypotheses, data will be gathered from 50 healthy, sedentary older men and women (65-75 years) prior to and following a 16-week unilateral exercise training program in which one leg undergoes resistance training and the other power training. The Specific Aims of this project are to identify the sex-specific effects of low-velocity resistance training versus high-velocity power training on: Aim 1) skeletal muscle function at the molecular, cellular and whole muscle levels, and Aim 2) protein expression and modification as well as size at the molecular and cellular levels. The within subject, unilateral intervention design provides a powerful model to minimize the effects of between-subject variability, and the translational approach will take advantage of our unique expertise with state-of-the-art measures from the molecular to whole body levels.

Eligibility Criteria

Inclusion

Inclusion Criteria:

Older adult (65-75 years old) volunteers will be healthy, by self-report, andsedentary, defined as no formal exercise program for the year prior to evaluation and < 2 sessions (30 min or more) of volitional exercise per week. Volunteers will beambulatory without the use of walking aids and living independently in the community.All participants will be required to obtain a physician's consent to participate inthe study, due to the exercise component, as is common practice in the Department ofKinesiology.

Exclusion

Exclusion Criteria:

History of major neurological or neuromuscular condition that may impact physicalfunction, including cerebrovascular disease, peripheral neuropathy, neurodegenerativedisease, demyelinating disease, cerebellar or extrapyramidal disease, etc.
History of myocardial infarction, angina, peripheral vascular disease, surgical orpercutaneous coronary artery revascularization
History of severe pulmonary disease (i.e., dyspnea that limits activities of dailyliving such as household ambulation and self-care)
History of rheumatoid arthritis
History of diabetes or other metabolic disease that may impact neuromuscular function
Uncontrolled hypertension (blood pressure > 140/90)
History of smoking in the past 1 year
Moderate to severe lower extremity arthritis or pain (i.e., pain on level walking orthat limits activities of daily living such as household ambulation and self-care)
Pain, muscle cramps, joint stiffness, dyspnea, angina, light-headedness or othersymptoms upon exertion
The use of beta-blockers, sedatives, tranquilizers, or other medication that mayimpair physical function
Individuals taking statin medications who report symptoms of muscle pain or myopathy
Body-mass index >30 kg·m-2, as increased fat mass may alter single muscle fiberperformance (Choi et al. J Gerontol A Biol Sci Med Sci 71:557-564, 2016)
Body-mass index <18 kg·m-2, as this may be an early sign of frailty
Must pass the Physical Activity Readiness Questionnaire for Everyone (PAR-Q+, inAppendix)
Any persons taking anti-coagulant medication or with known coagulapathies will beexcluded, due to increased bleeding risk from biopsy procedure
Participants with a contraindication for magnetic resonance testing, including apace-maker or other implant
Women will be postmenopausal, as defined as cessation of menses for at least 12 monthsprior to study
Men and women undergoing hormone replacement therapy, because this treatment maycircumvent normal age-related declines in sex hormone levels (if taken hormone therapymust have been > 5 years ago)
Unintentional weight loss of greater than 2.5 kg during the last 3 months
Currently participating in or have participated in a weight loss or exercise trainingprogram in the last year
An inability to understand written and spoken English
An inability to follow instructions, as determined by the investigators during theconsenting process

Study Design

January 01, 2018

March 31, 2024

Connect with a study center

University of Massachusetts
Amherst, Massachusetts 01003
United States
Active - Recruiting

Not the study for you?

Let us help you find the best match. Sign up as a volunteer and receive email notifications when clinical trials are posted in the medical category of interest to you.