Q Dear Fitness Explorer:

I'm doing my cardio- vascular and weight training work-out together. Which should come first? I'm trying to lose body fat and build muscle. --Sandy in Vestal

A Dear Sandy:

The key to answering your question is your fitness goal - the desire to lose body fat while building lean body mass (muscle). So the order in which you perform these cardiovascular and weight training activities is very important because each has its own energy source. Weight training work-outs use only glycogen for energy. (Glycogen is the form in which carbohydrates are stored in the body.) Cardiorespiratory activity uses both glycogen and stored body fat for energy. By beginning your work-out with cardio training first, you use up a significant amount of your glycogen stores, which means you will not have the energy left for a productive weight training work-out for building muscle.

I recommend that you do your weight training immediately before your cardiorespiratory training. On days when you do not do cardiovascular and weight training together - say you do one in the morning and one in the afternoon - it does not matter which you do first.

One final word, eating properly should be fundamental before any work-out. Good-Luck!

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