Muscle Damage and Disuse Atrophy

University of Exeter22 enrolled

Overview

Limb injury generally requires a period of recovery during which time the limb is often immobilised (e.g. with a cast or brace) resulting in a rapid loss of skeletal muscle. Despite the importance of muscle loss during injury, our understanding of how it occurs is incomplete. Several factors are likely to contribute, including a lack of muscle contraction and injury induced inflammation. In this study, the investigators will recruit healthy volunteers who will spend 7 days in a knee brace to replicate leg immobilisation. Prior to immobilisation, half of the participants will perform a single session of strenuous resistance exercise which is known to cause muscle damage and initiate an inflammatory response. This is designed to replicate the muscle damage and inflammation that occurs with injury. The remaining half of participants will not perform this exercise, allowing us to look at the additive effect of muscle damage and inflammation on muscle loss with immobilisation.

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

BASIC_SCIENCE

Masking

NONE

Enrollment

Conditions

Muscle Disuse Atrophy

Interventions

Eligibility

Sex: ALLMin age: 18 YearsMax age: 40 YearsHealthy volunteers:

Medical Language ↔ Plain English

Inclusion Criteria: * Aged 18 - 40 * BMI between 18 and 27 * Healthy, recreationally active, non smoker Exclusion Criteria: * Non-removable metallic implants (including heart pacemaker, cochlear implants, medication pumps, surgical clips, plates or screws) or claustrophobia * Use of nutritional supplements * Chronic use of over the counter medication * Any diagnosed metabolic disease (e.g. type 1 or 2 Diabetes). * Any diagnosed cardiovascular disease or hypertension. * Anyone with previous motor disorders. Anyone with a current musculoskeletal injury that may impair their use of crutches.

Outcomes

Primary Outcomes

Change in thigh muscle volume from pre-immobilisation

The volume of the muscles comprising the thigh after 2 days of immobilisation will be compared to pre-immobilisation values. This will be measured using MRI.

Time frame: After 2 days of immobilisation

Change in thigh muscle volume from pre-immobilisation

The volume of the muscles comprising the thigh after 7 days of immobilisation will be compared to pre-immobilisation values, and values obtained after 2 days of immobilisation. This will be measured using MRI.