HIIT Cardio....am I doing it right?
I started doing HIIT cardio for a change up when I'm bored ot when I don't have time to do a longer drawn out cardio session. I usually do it for 35 mins, 5 min warm up, 5 min cool down, 25 Interval. I always use a heart rate monitor. My warm up and cool down are in the fat burning zone, for me that is 136-144. When I do the interval part of the cardio I go for 1 min - 1 min 10 secs as hard as I can, my heart rate usually gets up to 175-180, then I recover for 1 min 20 secs at half that level. After that 1 min 20 secs my heart rate goes down to 155, but never any lower. My goal is fat loss, I am wondering am I doing this correctly to achieve optimal fat loss while holding onto the lean muscle?