Sarcopenia is an age-related disease associated with loss of muscle mass and strength. This geriatric syndrome predisposes elderly individuals to a disability, falls, fractures, and death. Fat infiltration in muscle is one of the hallmarks of sarcopenia and aging. Alterations in fatty acid (FA) metabolism are evident in aging, type 2 diabetes, and obesity, with the accumulation of lipids inside muscle cells contributing to muscle insulin resistance and ceramide accumulation. These lipids include diacylglycerol, lipid droplets, intramyocellular lipids, intramuscular triglycerides, and polyunsaturated fatty acids (PUFAs). In this review, we examine the regulation of lipid metabolism in skeletal muscle, including lipid metabolization and storage, intervention, and the types of lipases expressed in skeletal muscle responsible for the breakdown of adipose triglyceride fats. In addition, we address the role of FAs in sarcopenia and the potential benefits of PUFAs.