Recruiting

Observational Study

Sponsor:

University of Oregon

Code:

NCT05926219

Conditions

Aging

Muscle Atrophy or Weakness

Sarcopenia in Elderly

Sarcopenia

Eligibility Criteria

Sex: All

Age: 18 - 70+

Healthy Volunteers: Accepted

Interventions

Fatiguing Exercise

Study Details

Brief summary:

This study is investigating changes to the proteins in skeletal muscle that contribute to reduced muscle size and muscle function that occurs with aging.

Conditions

Aging

Muscle Atrophy or Weakness

Sarcopenia in Elderly

Sarcopenia

Study ID

NCT05926219

Start date

Nov 6, 2017

Status verified date

May, 2026

Completion date

Jan, 2027

Anticipated

Primary completion date

Jan, 2027

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 18 - 70+

Healthy Volunteers: Accepted

Inclusion Criteria:

  • Adults between the ages 18-35 or 65-80 years
  • Healthy by self-report
  • Willing to participate in all aspects of the study design including muscle biopsy, unilateral exercise, and physical activity monitoring
  • Fluent in English (due to lack of translation services, it is not practical to conduct the study using a language other than English).

Exclusion Criteria:

  • Orthopaedic limitation (severe knee osteoarthritis, prior joint replacement, etc.).
  • Volunteer has dementia or related mental issues that potentially put the subject at risk as determined by prior diagnosis.
  • Volunteer has known untreated endocrine disease (hypo/hyper thyroidism, Addison's Disease or Cushing's syndrome, etc.)
  • Volunteer has untreated/poorly-controlled hypertension (stage 2, per American College of Cardiology \[>140/90 mmHg\]).
  • Volunteer has significant heart, liver, kidney or respiratory disease.
  • Volunteer has diabetes (insulin dependent or non-insulin dependent).
  • Volunteer has known coagulopathies.
  • Volunteer has taken anabolic steroids in the prior six months.
  • Volunteer has received treatment for cancer (other than effective Mohs Surgery for successful removal of basal cell or squamous cell carcinomas)
  • Unexpected weight loss >5kg is last 12 months
  • Volunteer is an active smoker or quit within the last year.
  • Volunteer has known current alcohol or drug use disorder (AUD; defined as binge drinking of >4 days in the last month. Binge drinking is >5 drinks for men and >4 drinks for women, per occasion). Or, if a volunteer reports drinking in excess of "low risk" per NIAAA (>7 drinks/week for men and >3 drinks/day for women and >14 drinks/week and >4 drinks/day).
  • Volunteer has a diagnosed neuromuscular disorder.
  • Volunteer has allergy to lidocaine.

Study Design

Enrollment

24 participants

Anticipated

Intervention Model

Single group

Primary purpose

Basic Science

Interventions and Outcome Measures

Arms

experimental: Fatigue

Volunteers will perform one-legged knee extension exercise until fatigue while seated on an ergometer. Volunteers will then undergo bilateral skeletal muscle biopsies of the vastus lateralis muscle in their thigh.

Interventions

Fatiguing Exercise

Volunteers will perform knee extension exercise of the dominant limb while seated in a chair designed for exercise of the knee extensor muscle group. The chair will be equipped with a lever arm, aligned with the axis of rotation of the knee and fixed to the distal shank, 2 centimeters proximal to the ankle joint. The lever arm will be instrumented to provide resistance and measure velocity. The volunteers will perform 3-5 maximum voluntary contractions (MVC) to determine peak torque. Once established, volunteers will rest for 5 minutes before initiating the fatigue protocol, whereby they will perform repeated MVC of the dominant limb against resistance equal to or less than 50% of MVC until range of motion cannot be maintained. Because the goal of this exercise is to uniformly fatigue the quadriceps muscle group, this exercise will be performed continuously. It is expected to take between 1 and 3 minutes to achieve the desired level of fatigue.

Primary outcome measure

  • Phosphorylation of myosin binding protein c (MyBP-C) [ Time Frame: One week after the participant undergoes the biopsies. ]

Central Contacts and Locations

Central contacts

Damien M Callahan, Ph.D.

541-346-5040damienc@uoregon.edu

Karen Wiedenfeld Needham, BS

541-346-7610needham@uoregon.edu

Locations

University of Oregon

Recruiting

Eugene, Oregon, United States, 97403

Contacts

Damien M Callahan, Ph.D.

458-205-5343damienc@uoregon.edu

Principal Investigator:

Damien M Callahan, Ph.D.

More Information

Sponsor

University of Oregon

Last update posted

Sep 9, 2026

Last verified

May, 2026

Keywords

  • muscle
  • aging
  • elderly
  • myosin
  • protein
  • sarcomere
  • exercise
  • function
  • atrophy
  • contractile
  • strength
  • balance
  • mobility
  • MyBP-C
  • fiber
  • biopsy
  • skeletal muscle
  • fatigue

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by University of Oregon on 2026-09-09.