Recently, researchers in Finland made the discovery that some people’s bodies do not respond as expected to weight training, others don’t respond to endurance exercise and, in some lamentable cases, some don’t respond to either. In other words, there are those who just do not become fitter or stronger, no matter what exercise they undertake. To reach this conclusion, the researchers enrolled 175 sedentary adults in a 21-week exercise program. Some lifted weights twice a week. Others jogged or walked. Some did both. Before and after the program, the volunteers’ fitness and muscular strength were assessed. At the end of the 21 weeks, the results, published earlier this year in Medicine and Science in Sports and Exercise, were mixed. In the combined strength-and-endurance-exercise program, the volunteers’ physiological improvement ranged from a negative 8 percent (meaning they became 8 percent less fit) to a positive 42 percent. The results were similar in the groups that undertook only strength or only endurance training. Some improved their strength enormously, some not at all. Others became aerobically fitter but not stronger, while still others showed no improvements in either area. Only a fortunate few became both fitter and more buff. As the researchers from […]