Spinal muscular atrophy (SMA) is a genetic condition that weakens muscles throughout the body. This makes it difficult to move, swallow, and in some cases breathe. SMA is caused by a gene mutation ...

Everyone is familiar, at least hand-wavingly, with the distinction between slow-twitch and fast-twitch muscle-fiber types. The former are great for running marathons; the latter are ideal for ...

The muscular system works to control the movement of our body and internal organs. Muscle tissue contains something called muscle fibers. Muscle fibers consist of a single muscle cell. They help to ...

More mileage during training results in faster finish times, right? Recent research suggests that might be true for some runners—but not for everyone. Before and immediately after each training period ...

When you picture different athletes—marathon runners, gymnasts, and Olympic weightlifters, for example—you likely categorize them instinctively by their height, size, and build. But the differences in ...

Fast-twitch fibers help with explosive movements like sprinting and weight lifting. Genetics and training influence the distribution of fast-twitch and slow-twitch muscle fibers. Doing strength ...