Aerobic activity can protect your heart, help you control your blood glucose levels, and facilitate weight loss. But according to previous studies, a combination of aerobic and resistance training provides greater benefit to people with diabetes. A recent small study suggests the type of resistance training matters, too. Researchers at the University of Utah found that a combination of aerobic activity and “eccentric” resistance exercises--those negative contractions that lengthen the muscle, such as when you lower a dumbbell during a biceps curl, as opposed to “concentric” contractions that shorten the muscle, like when you raise a dumbbell during a biceps curl--does more than aerobic activity alone. At the end of a 16-week program, those who used a recumbent eccentric stepper in addition to performing aerobic activity gained thigh muscle and lowered their body mass indexes, while aerobic-only exercisers experienced a decrease in thigh muscle mass.
Source: Physical Therapy, November 2008