Actually, there might be a reason for doing weights first and cardio later: lifting weights needs a lot of free energy, in the form of carbohydrates. The cardio training would consume a lot of these, to the point where you would have very few reserves. So, if you do cardio first, you might not be able to lift as much weight, therefore compromising your workout. Besides, since the goal of cardio many times is to burn fat, it's better to give a "kick in" lifting weights — burning some of your sugars — so that when moving to cardio, you start to burn fat earlier on during the exercise. Or is it?...

With all of the various fitness personalities and vast numbers of aerobic exercise videos and programs featuring low-intensity workouts claiming to maximize fat burning, it's no wonder that you are second guessing your workout regimen. The argument behind this supposed theory is that low-intensity aerobic training allows your body to use more fat as an energy source as opposed to energy from carbohydrates, accelerating the loss of body fat.

There is a difference in the percentage of calories utilized from fat vs. carbohydrates, depending upon the level of exercise intensity. People expend around 60 percent of their calories from fat based caloric reserves while performing low-intensity exercise. This number decreases to 35 percent when performing high-intensity exercise. However, people will still utilize more overall calories and total calories from fat when exercising at a high intensity level than at a low intensity level for the same amount of time. Having said this, your body does not burn all of the available calories from carbohydrates and then move on to burning calories from fat. Your body utilizes both at the same time.

The suggested order for completing a workout needs to consist of a short warm-up, some strength training, a cardio aspect, and a brief cool-down. The warm-up and cool-down can include stretching, cardio, or both. When you do the cardio portion of your workout simply depends upon if you want to have either more energy or pre-fatigue your muscles for your strength training. For example, you can do a bit of cardio to warm-up the muscles, do your strength training, and then complete a more strenuous cardio portion, cooling down at the end with some stretching. On the other hand, you can do all of your cardio at the beginning of your exercise session to pre-fatigue your muscles, do your strength training, and then cool-down with stretching.

You can check out the following resources for additional info:

"Warm Up to Work Out" on the American Council on Exercise website

Cedric X Bryant's book, 101 Frequently Asked Questions about "Health & Fitness" and "Nutrition & Weight Control"

For a more personalized consultation, you may want to talk with a certified personal trainer at your health club concerning the latest in fitness research and on the best program design for what you are trying to accomplish in the gym. Bottom line — as long as you are exercising, including warming up at the beginning and cooling down at the end with some stretching, the order of your cardio and strength training in between doesn't really matter.

Alice

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