ok, so I am quite new to the whole exercising thing. I am 26, and started going to the gym about 3 weeks ago.
Yesterday I went to the gym, and at level 14 on the cross trainer, doing 65 reps per minute, my heart rate stayed roughly between 145 and 150 bmp, which is fine. Today on the other hand, I went to the gym, and within about 10 minutes at level 14 doing 65 reps per minute, my heart rate was well up over 160. I had to come down to level 12 and 60 reps per min to get it back under 155bmp. Anyone care to speculate why that might be the case?
I don't really want to exercise at over 80% of my max heart rate, as I get so tired and can't carry on for more than a few mins when my HR gets that high. I just don't understand why today was such a difference....