I went to the gym near my office yesterday for the first time in almost 2 years I think. I plan on going there to spend some time on the elliptical on my "off" days from walking/running, i.e. Tuesday/Thursday. I was wearing my VFF's as I didn't want to risk any problems with staff if I was BF. So I was on the elliptical for about 25 minutes, kept my HR up around 145-155 the whole time. The little chart on the machine said 80% of max HR for a 30 year old should be about 152, I'm 32, so not bad. After that, and I don't plan on doing this every time, I got on the treadmill, just curious what it was like to walk and run on the TM with a mid-foot strike. I ran for 90 seconds at 10-11 min/mile pace, and after that my HR was up to 176! I'm no doctor but that sounds a little dangerous. Is it? Or am I just being paranoid? *edit* also I did not feel much of any pain in my left leg while on the elliptical or while running on the TM. I'm starting to think my left calf issues are because of the crown in the road.