I m concerned about my heart rate. I ve been running or rowing for all of my adult life. 45 yo, 6 6 , 215lbs, barely drink, eat well. For the past 3-4 months I ve been slacking a bit as far as training. In the attempt to get back in shape over the last few weeks I ve figured out my heart rate is very low. In the 30s before rising out of bed, 40s when sitting around, and 60s and 70s when trying to workout the max I can get it to is 110 during a run or row. Today I ran (or fast walk) for over 30 minutes with a heart rate under 80. I feel great otherwise. Any recommendations on a jump start so I can push harder?