As title really.. i am going to introduce HIIT into my weekely routine... i do 3 weights sessions a week and am looking to add a couple og HIIT sessions for a bit more fat loss.

what is a good time scale to aim for... 5 min warm up, 20 min session, 5 min warm down??

also have you got any advice on whats best? rowing? running? press ups? sit ups? i dont really know where to start.

thanks in advance