Metabolic Muscle Memory: The Bad News

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A few weeks back I posted a little piece on keeping the weight off during the holidays. I cited some work that shows how and why formerly overweight folks have a tougher time keeping the weight off than people who have never been heavy.

While I was rooting around for studies on gut microbiome, I ran across this little gem of a study that offers another piece to the puzzle of how obesity affects the metabolism, even after extra weight is lost.

Altered anabolic signalling and reduced stimulation of myofibrillar protein synthesis after feeding and resistance exercise in people with obesity.

The gist of it is, while the obese generally also carry more extra muscle weight in addition to extra fat, that muscle is of a lower quality metabolically. One consequence of this condition is the obese do not synthesize protein or build contractile tissue as efficiently as normal weight folks. So their efforts to build more muscle (to make their bodies metabolically more active to burn more calories by increasing muscle mass) is thwarted. Worse, obese muscle tissue appears to "remember" its obese phenotype and continues to resist building contractile tissue after the weight is lost. Can't win for losing, sometimes.

Unfortunately, there isn't much that science has to offer the formerly obese in this regard except to stick with a eating and exercise plan, accentuate real food and be patient. It's still better to exercise and eat well than not, even though it will always be a bit harder to succeed. For those who are not struggling with their weight, the best tip is to not let yourself get fat in the first place.

As I have mentioned before, I have to manage my weight ongoingly. I have come to think of this as much like managing any other chronic health condition. There are things that work in my favor and things that do not, so I try to do what works. Most of the time. Currently I could say my obesity is "in remission" which may not be the most scientifically accurate description, but as a working analogy I think it is apt.

I used to joke that that even at my skinniest adult weight (30 years ago, 148 lbs, while cycling 250-300 miles a week) there was still a fat kid inside me screaming to get out. Like any good joke, there is a truth which underlies it. Those of you who have known me for awhile know that the fat kid has made a successful jail break from time to time.

Beals, J. W., Skinner, S. K., McKenna, C. F., Poozhikunnel, E. G., Farooqi, S. A., Vliet, S. van, … Burd, N. A. (2018). Altered anabolic signalling and reduced stimulation of myofibrillar protein synthesis after feeding and resistance exercise in people with obesity. The Journal of Physiology, 596(21), 5119–5133. https://doi.org/10.1113/JP276210

Randy Hauer