By Kathryn Doyle Reuters Health – For adolescents, low cardiorespiratory fitness and poor muscle strength increase their risk for type 2 diabetes later in life, regardless of body weight, according to a study of young men in Sweden. “Not only were both low aerobic and muscular fitness linked with a higher long-term risk of diabetes, but this was true even among those with normal body mass index,” said lead author Dr. Casey Crump of the Icahn School of Medicine at Mount Sinai in New York City.