Little Jeremiah has a muscular disease called muscular dystrophy. This disease is caused by gene mutations that interfere with the production of the proteins necessary for healthy muscle production.
The major symptoms of muscular dystrophy include progressive muscle weakness. This means that Jeremiah can't participate in a lot of sports of physical activity because he doesn't have as much muscle.
Since Jeremiah's muscles are weak, he often falls or has trouble standing up because his muscles are so weak. Because of this, Jeremiah frequently visits the doctor for muscle pain or broken/sprained bones.
There is no cure or permanent treatment for muscular dystrophy, but the severity of symptoms can be lessened through treatment options including medications, therapy (light physical therapy or light exercise to stimulate muscles), and surgery if absolutely needed.
Muscular dystrophy is a result of a malfunction of the muscular system. There are certain genes that are responsible for producing proteins that protect muscle fibers. These genes are defective in people that have muscular dystrophy, and their muscle cells are unable to function properly and degenerate from lack of protection.
A special protein that Jeremiah lacks in his muscle cells is dystrophin. This protein is responsible for distributing the force of a muscle contraction across the who muscle cell - from the inside to the outside (cell membrane). Because Jeremiah doesn't have this protein, his muscles continue to weaken and cannot repair themselves after contractions.
I can't gain any muscle.... they only keep weakening :(