SHORT ANSWER, NO! The end! Okay, but there is more to the story. I think I know my readers and if I’m correct you guys can settle for a quick answer but you like more information also… especially to a somewhat complex question. So here is a little more background on why muscle cannot magically turn to fat when you stop working out or get older and why I’m writing this blog.
I’M WRITING THIS BLOG because, as you may know, I have a lot of muscle mass and for some reason random people love to start a conversation just so they can remind me that my muscle will turn to fat one day. This has been happening to me for over 20 years. And I get frustrated for two reasons…1) they’re usually not very fit people and they seem to tell me this to justify why they are the way they are and 2) Its total BS but they believe it to the point that it comes across as a lecture and warning. Now I will admit that not all who tell me this are trying to justify, and I don’t mean to sound mean, but the ignorance in the statement is really frustrating. But I quickly remind myself that they really don’t know better and here’s what I think they are trying to say.
MUSCLE CELLS GROW large and multiply (hypertrophy) when you exercise and if you stop exercising, the muscles will get smaller (atrophy). Muscle cells will not convert to a different cell type and turn into fat. What does tend to happen is just after a few weeks of not working out or no exercise, you can lose some of that muscular look. A few more weeks after that, you may see some noticeable signs of atrophy. Along with the atrophy comes the changes in metabolism which can lead to more fat storage if your diet hasn’t adjusted properly to the decrease in exercise.
IN CONCLUSION, muscle cells cannot physically, scientifically, or mysteriously turn into fat cells. You can, however, lose muscle due to not using them and get fat because you are eating too many calories (and/or other factors). My advise would be for you to consult with a sports nutrition coach or a health coach that can help you with your lifestyle change so you can maintain the physique you want.