Why should children with Duchenne muscular dystrophy avoid eccentric contractions?

Children with Duchenne muscular dystrophy (DMD) should avoid eccentric contractions primarily because such muscle actions can lead to increased muscle damage. Eccentric contractions occur when the muscle lengthens while under tension, such as during activities like lowering a weight or descending stairs. In individuals with DMD, the muscle fibers are already compromised due to the genetic mutation affecting dystrophin production, which plays a critical role in muscle integrity.

When these children engage in eccentric contractions, the strain can exceed the muscle's ability to repair itself, resulting in greater muscle fiber damage. This can exacerbate the progressive muscle weakness characteristic of DMD and lead to further complications, including increased pain and recovery times. Therefore, careful management of physical activities to focus on minimizing eccentric load is crucial to preserve muscle function for as long as possible in children with DMD.