Young People's Muscle Fat Burn: What Changes with Age?

Do you know that muscles can store fat? Inside muscle cells, there's intramyocellular lipid (IMCL) and outside, it's called extramyocellular lipid (EMCL). Then, there's fat between muscles, known as intermuscular adipose tissue (IMAT). Scientists think these fats play a role in energy production in our muscles. But does muscle oxidative capacity, which affects energy production, have anything to do with these fats? A study checked this out in young and older folks. They measured oxidative capacity by how fast muscles regain oxygen after exercise. IMCL, EMCL, and IMAT were checked using fancy imaging tools. In young people, muscle fat inside cells (IMCL) was linked to better oxidative capacity. But in older people, this link wasn't seen. Plus, neither EMCL nor IMAT seemed to matter much in either group. This study hints that in young adults, the fat inside muscles can help in energy production. But as we age, this relationship changes. It's like how older muscles might not use stored fat as efficiently as younger muscles do.