The Amazing Return of Muscle Mass

One of the most surprising things about my road to recovery has been how quickly I’ve regained my lost muscle mass.

After three months of inactivity, my muscles were soooo deflated. I tried to do some pool running, but, honestly, it was so boring, I wasn’t great to getting that in regularly. By the time I got the all clear in early March, I was a just a shell of my former running self, literally.

One night in early March I was using the stick on my calves, and the difference made me distraught! My calves were like saggy old lady boobs, I told my boyfriend. Flash forward seven weeks, and—if my FitBit Aria scale is to be trusted—I’ve gained 7 lbs of muscle mass. That’s 1 lbs of muscle gain a week!

Here’s that data graphically:

I was astounded by that. How is that even possible?? After some routine Internet searching, I found that the answer might be in my muscle nuclei.

As it turns out, when you exercise regularly, your muscles’ cells adapt by producing more nuclei to provide more energy and better power that exercise. And when muscles atrophy, those extra nuclei stick around for quite some time, and provide a kind of “muscle memory” that allows you to regain muscle quickly once you resume training.

Pretty fascinating stuff! And it helped make me feel better when I saw the numbers on the scale tick up, even as I was closely watching my diet (more on that in another post) in an effort to shed some of the extra fat I gained in my three months off. Now I’m putting more of an emphasis on the body fat percentage number the scale spits out, as imperfect as that is. I find that there is a lot of variation from day to day, but that long term trends on that front are pretty valid.

Unfortunately, I only bought my FitBit Aria scale in January (when I noticed I was starting to put on some weight after a month of not running and eating a lot of Christmas treats), so I don’t have body composition data from before my injury to compare with, but my three months of data so far this year is promising. I’ve gone from a roughly 26% body fat in January to a 21% body fat recently.

I’m aiming to get down to the 17% range, per some information in Matt Fizgerald’s book Racing Weight. I think these last 4% are going to be the hardest, but I’ll keep you posted!

Cheers,

KK