Overview
Most of the basic features of muscles have remained unchanged across vertebrate evolution. As a result, all muscles operate with a similar set of intrinsic physiological constraints, which must ultimately define the boundaries to the speed, force and cost of movement. Research in my lab aims to understand how organisms overcome these constraints to meet the diverse mechanical demands of movement. In my lab, we use an integrative approach to reveal how interactions between muscle physiology, muscle-tendon structure, and biomechanics ultimately determine locomotor performance.
Skeletal Muscle Structure
Muscle fibers and fascicles are embedded in collagenous scaffolding which contributes to muscle’s passive stiffness, function to provide structural integrity and transmit forces. Muscle ECM has been shown to become fibrotic due to atrophy, aging or neuromuscular disorders and our group is examining how changes in the mechanical properties of the ECM affect physiological function. We are primarily using an established aging model system to address basic questions regarding muscle-collagen interactions. This work has been funded by the US National Science Foundation and the National Institute of Health.
Elastic Mechanisms in Locomotion
Most muscles operate in series with tendons, which function as efficient biological springs to store and release strain energy. Tendons can decouple length changes of contracting muscle from the motion of the joint. As a result tendons have the potential to minimize the energetic cost of locomotion, amplify muscle power, and protect muscles during locomotion . Specifically we have focused on how tendons can reduce the rate of energy input to muscles during activities that require muscles to dissipate mechanical energy.
Muscle function during controlled decelerations
While skeletal muscles are often thought of as the body’s motor, our muscles are also used to decelerate our bodies during common everyday tasks. We have used the coordinated landing of toads as a model system to explore the neuromuscular control needed to safely and efficiently dissipate mechanical energy. Our research aims to better understand the sensory modalities used to inform control strategies, how passive tissues interact with contracting muscles, and how specializing for this function drives variation in muscle properties.
