Started a HIIT program, every other day, running. It's going to kick ass (meaning it kicks my ass). I'm also weight training, alternating muscle groups every day (day 1 chest and arms etc, day 2 back and shoulders etc.) My question is whether or not it's okay to do long distance on the days I'm not HIIT (every other day). In the sake of weight loss, will this just burn my lean mass or will it rev my metabolism even higher as I hope it will? Thanks for any help.