I've done HIIT before and I've always been impressed by the quality and effectiveness of the workout in such a short ammount of time. I recently read an article (http://www.musclemedia.com/training/hiit.asp) on more of the theory behind why it works.

I was wondering if it would be effect to do HIIT twice a day - once in the early morning and once in the afternoon? Has anyone tried it, or are there any drawbacks that are obvious to others?

Jeff

I'm not an expert on HIIT by any means. However, with that being said, I thought the entire purpose of HIIT was to allow for more/better results with less training time because of its supposed effect on your metabolism over a substantial period of time.

It seems to me that doing HIIT twice in one day would be completely unnecessary.

Why not just do HIIT in the morning and then weight training in the afternoon?

doing HIIT once a day is plent IMO..

you have to realize when you do extremly intense cardio or training.. IE HIIT or max ot.. for a period of time your comprimise your immune system.. you become more suseptable to illness for a duration (i am not sure how long)..

doing it twice maybe a bit extreme, also depending how many times a week you do this twice.. you have to be careful, over training with intense cardio and weights really sucks.. your body just comes to a hault and for a week you a grinding away with next to zero energy