FRESNO, California (KFSN) --It depends on your goals. Many personal trainers think that performing strength training before cardiovascular exercise is best so you can get the maximum strength performance from your workout.
Most likely, the intensity of the activity, not the type of exercise, determines the "fuel"-- either fat, carbohydrate or protein -- that is used. However, if you strength train first, it is possible that muscle fatigue incurred from the strength training could cause them to decrease the intensity of their cardio workout, thus leading them to expend fewer calories over the workout as a whole.
If your goal is to increase aerobic endurance or lose weight, then you should perform cardiovascular exercise first. If the primary goal is to increase muscular strength, then you should perform strength training first. Work toward your goals first, and then follow up with the other training.