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Aerobic vs. Weight Training


Most of my clients aim to lose body fat. I’ve been told that aerobic training and weight training are not compatible as one is aerobic and the other is anaerobic. As a result, these cancel each other out. Is this true? And if so, why? Which is better for aiding in fat loss?


Aerobic training and weight training are not compatible only if the main goal of a client is to gain muscle. The aerobic training makes it harder to build mass.

Aerobic training and weight training are both important for the goal of fat loss. In fact, weight training may actually be more important than cardio to lose fat for a few main reasons. When someone is performing cardio for an extended time, he or she is burning a significant amount of calories during the workout. However, once the cardio is stopped, the calorie burning soon slows down and returns to a resting state, usually within 30 minutes. During weight training, people are burning an increased amount of calories, but more importantly, they continue burning more calories for up to two hours after their workouts, according to studies done at John Hopkins University. This is commonly referred to as “the afterburn” and occurs because the body is breaking down muscle (a process called catabolism) during weight lifting. The body then needs to repair this broken down muscle (a process called anabolism) and build itself stronger. These processes require the body to burn a lot of calories, so even when your clients are sitting down and watching TV after their workouts, they will be burning more calories.

At rest, your body burns about five calories per day to maintain one pound of body fat. At rest, your body burns about 50 calories per day to maintain one pound of lean body mass (muscle). This illustrates how significantly one’s metabolism is increased by having more muscle. The more muscle one has, the higher his or her metabolism will be.

A common myth is that weight lifting will cause female clients to get bigger. As long as they lift lighter weights and do more repetitions, they will just get more tone and lean. Lean muscle actually takes up less space than fat does. A good rule to follow is to have them perform 12 to 15 repetitions with a weight they can lift that many times but become fatigued by the last few reps. Start with one set for deconditioned clients and progress to two or three sets.

Performing cardio after weight lifting helps burn some more calories and helps rid the body of lactic acid (which causes people to get sore after a workout). Recent studies have also shown that performing cardio immediately after a weight lifting workout can increase the percentage of fat calories burned during the cardio routine.