Regular exercise is key to weight loss and maintenance. And since there’s no consensus on whether the ideal workout is aerobic or resistance training, your best bet is to do a little of both. Resistance training is especially important for people over 30, who will otherwise begin to lose bone density. Contrary to popular belief, abdominal crunches are not going to melt away belly fat, though they will help build muscle that could help define the area. And since muscle mass has a higher resting metabolic rate and energy expenditure than fat, it could help you trim down. Mix up your workout routine with these exercises that flatten your belly—without a single crunch.