The American College of Sports Medicine (ACSM) is a professional organization for exercise scientists, sports medicine doctors, sports dietitians, sports psychologists, and other health professionals, educators, and researchers who work with athletic people. ACSM’s Annual Meeting is a hotspot for the latest sports nutrition news. More than 4,000 members gathered in Salt Lake City to present their research and discuss current trends and topics. Here are a few sports nutrition highlights that might be of interest.
• Weight: When people gain weight, they also gain muscle as the body adapts to be able to carry the heavier load. Hence, people with obesity tend to have a lot of muscle—more than leaner people! The quality of the muscle, however, in terms of strength and power, is diminished if they are not physically fit.
When people with obesity lose weight, they similarly lose muscle, in part because they have less weight to carry around, and also because the body, when in energy deficit, breaks down muscle for fuel and does not have the energy needed to make new muscle. The same holds true for dieting athletes, such as weight-conscious runners.
Among people who use GLP-1 weight loss meds, about 25% of the weight lost can be muscle. While that is to be expected, it can also be lessened by doing resistance exercise. Hence, strength training should be a fundamental part of every weight reduction program—especially among dieters who eat minimal calories, such as those who use GLP-1 meds and runners who believe “lighter is better.” (Not always true!)
• Muscle-building. To build muscles, you need to lift weights, do push-ups, or participate in some type of resistance exercise. Consuming a high-protein diet or taking creatine (or even hormones such as testosterone) does NOT build muscle. As exercise physiologist Stu Phillips explained, strength training is what “bakes the cake”; creatine is the sprinkles on the top.
The best strengthening exercises are the ones you enjoy. If you prefer to lift lighter weights than heavier ones, that’s okay. Doing 20 to 25 reps of lighter weights will give you the same gains as lifting 8 to 12 reps of heavier weights. The key is to lift until the muscle is fatigued.
Athletes vary in the amount of muscle they can build; some are “hard gainers.” In general, men gain more muscle than women, but that is relatively speaking. A female runner can gain the same percentage of muscle as a male runner That is, with a strength training program, a 1% gain for a 150-lb. male would be 1.5 pounds, but only 1 pound for a 100-lb female.
According to exercise physiologist Trent Stellingwerff, if you feel as though you’ve hit a plateau when lifting weights, your best bet is to stay consistent with your program and fret not about “changing things up.” For more information about the most effective ways to build muscle, take a look at ACSM’s 2026 Position Stand on Resistance Training Prescription for Muscle Function, Hypertrophy and Physical Performance.
• Given the plethora of trendy info about nutrition supplements, many athletes are taking products that make amazing claims but have no science to back them up. Buyer beware: the nutrition supplement industry is poorly regulated! Supplement makers do not have to prove their products are safe. Only after a product has come on the market and created health issues does the FDA step in.
Nancy Clark MS RD counsels both fitness exercisers and competitive athletes in the Boston-area (617-962-4382). Her best-selling Sports Nutrition Guidebook is a popular resource. For more information, visit NancyClarkRD.com.