Here's the optimized version of the text:
What is Loss of Muscle?
Muscle loss, also called muscle atrophy, occurs when muscle cells shrink or degrade. This leads to reduced muscle strength and mass. Some key causes of muscle loss include:
- Aging - Muscle tends to gradually waste away as part of the natural aging process after age 30. The rate of muscle loss speeds up significantly after age 60.
- Inactivity - Not exercising leads muscles to weaken and shrink over time. Bedrest, cast immobilization, and low physical activity all spur muscle loss.
- Malnutrition - Consuming too few calories, not enough protein, or inadequate vitamins/minerals leads to muscle breakdown.
- Diseases - Certain medical conditions like cancer, kidney disease, AIDS, and heart failure are linked to accelerated muscle loss.
Losing muscle mass matters because it negatively impacts strength, mobility, and vitality. However, regular exercise with proper nutrition can slow, stop or reverse age-related muscle loss. Supplements and medications are also sometimes used to treat muscle atrophy.