Submitted By: James Hill, New Jersey

1. Is it OK to weight train or perform cardio (sprint/jump/bike) on an empty stomach first thing in the morning?

2. Is it OK to remain in a fasted state for 5-6 hours after the cardio session (I understand why this is ill-advised for lifting)? I've read a lot on the health benefits of intermittent fasting. As such, a few days a week on cardio and off-days, I try to fast 20-24 hours to take advantage of the additional hormonal/fat burning benefits.


1. It is okay to perform moderate intensity cardio exercise on an empty stomach first thing in the morning. I recommend against more intensive training in a fasted state.

2. There are different fasting methods. Some fasts involve eating nothing and drinking only water, then there are water/juice fasts, and fasts in which you take only nutritional supplements/food extracts but consume no calories. Electrolytes should be restored after vigorous physical activity, and plain water does not quench this need. In addition, certain nutrients are instrumental in fat burning (including, for example, chromium, carnitine, and CoQ10, each of which can be found in food) and evidence suggests that antioxidant intake immediately after intense training facilitates recovery. For these reasons, a complete or water-only fast after training is counterproductive in my opinion.