The question of whether or not to perform weight training and cardio on the same day has been a long debated issue. Some people believe that if the two types of exercises are performed in close proximity, the strength and growth of muscles are stunted. To test this theory, researchers in Ontario and Sweden conducted studies on both active, young men and sedentary, middle-aged men. Their results were published in The Journal of Applied Physiology and Medicine & Science in Sports & Exercise.
Before conducting the studies, the researchers believed that the body’s response to either exercise would dominate over the other and limit results. In essence, they believed that the tests would show that each exercise should be done individually.
However, the results of the studies actually showed that performing weight training and cardio on the same day had no negative effects on endurance training, resistance training, or muscle growth. In fact, they found that doing 50 percent less of both types of exercise on the same day produced the same results as doing full workouts devoted to one or the other. So, if you’ve been doing your weight training and cardio on separate days, combine your workout to get more bang for your buck.