Among my clients, I’ve observed that skinny athletes who have trouble gaining weight tend to be good fidgeters. They twiddle their fingers, swing their legs backand forth while sitting, and seem unable to sit still. All this involuntary movement burns calories. In comparison, the folks who complain about their inability to lose weight generally sit calmly, barely blinking their eyes. They may complain they have a “slow metabolism.” Doubtful. Their metabolism is likely normal, but their propensity to sit calmly is the problem. Compared to the fidgeter, they save themselves a lot of calories!
The technical term for the spontaneous movement often seen in skinny people who have difficulty gaining weight is Non-Exercise ActivityThermogenesis or N.E.A.T. NEAT includes not only fidgeting but also pacing while you talk on the phone and standing (not sitting) while you talk with a teammate. If you overeat, activation of NEAT helps you dissipate excess energy by nudging you to putter around the house more, choose to shoot some hoops, or (yikes!) feel motivated to vacuum and clean the house. If your body’s ability to activate NEAT is low, then you likely gain weight easily. NEAT can predict how resistant you'll be to gaining weight.
If you are overfat, the next time you start to complain about your slow metabolism, think again. Maybe you should start fidgeting and moving more throughout the daytime?
If you are skinny, the next time you complain about being unable to gain weight, think again. Can you try to stop fidgeting and pacing?
For help with gaining weight: Nancy Clark’s Sports NutritionGuidebook, Chapter 14: Add Bulk, Not Fat
Levine JA, Ebernath NL,Jensen MD. 1999. Role of nonexercise activity thermogenesis in resistance tofat gain in humans. Science.283(5399):212-4.