Q: mike, when I do cardio, I am confused between training as at my hardest for 30 mins, or training in the 'fat burning zone' on my electronic, heart sensor cross trainer. does training in this zone actually work? and if so, how long will I need to train in this lower intensity zone for? thanks for the great website

A: The 'fat burning zone' is mostly marketing hype. For regular cardio, I would advise training near your maximum effort for those 30 minutes. Pick a pace that you can maintain for the entire duration and stick with that. It may or may not fall in the 'fat burning zone' and it doesn't really matter.

All other things being equal, I would also recommend doing cardio on separate days or at least separate times from weight training (so you're fresh for both). If you have to do them back-to-back, I would do weights first and then cardio.