Stuart Little No More: Effects Of High Resistance Wheel Running On Skeletal Muscle Hypertrophy And Strength In C57BL/6 Mice

Skeletal muscle comprises approximately 40% of body mass in adult humans; thus, maintaining skeletal muscle mass throughout the lifespan is critical to maintain normal function and health. To study the molecular and cellular mechanisms of maintaining muscle mass, animal models have been utilized as they benefit from control over diet and exercise regimen. Further, the collection of whole tissues throughout the body, allow for greater depth of exploration into the molecular and cellular mechanisms that regulate muscle mass. Mice voluntarily run long distances when provided a running wheel. To mimic human resistance exercise models, external resistance can be applied to the running wheel and progressively increased. Numerous studies have demonstrated that loaded wheel running models induces adaptations commonly seen with resistance exercise in humans, such as muscle hypertrophy and stimulation of muscle protein synthesis. Loaded wheel running models in mice involving low to moderate added wheel load often fail to deter mice from running great distances, which is more reflective of an endurance/resistance training model. Elucidation of hypertrophic responses to high resistances, which may further bias the training stimulus towards resistance training may help improve the effectiveness of the loaded wheel running model, and consequently, future research in this field.