why am i losing muscle mass in my legs

Losing muscle mass in the legs can be caused by several factors, including inactivity, aging, nutritional deficiencies, and underlying medical conditions. Inactivity is one of the most common causes—if muscles are not used enough, they shrink and weaken over time. This can happen due to a sedentary lifestyle, prolonged bed rest, or limited mobility due to injury or illness. Aging naturally leads to muscle loss, a condition known as sarcopenia, where muscle protein synthesis declines, reducing muscle mass and strength gradually. Nutritional deficits, especially inadequate protein intake, also impair muscle maintenance and growth, accelerating muscle loss. Certain diseases and nerve damage or neurogenic conditions can cause muscle atrophy by disrupting the nerve signals that stimulate muscle use. In summary, muscle loss in the legs can arise from disuse, poor nutrition, age-related changes, or medical conditions affecting muscles or nerves, many of which may be reversible or manageable with treatment and lifestyle changes.