It seems that after almost every ride, especially intense rides (which most of them are) it takes quite a while for my heart rate to return to resting rate. My resting rate is about 55 bpm. Around 30-60 minutes after a ride my heart rate will still be around 75-80 bpm. This seems pretty high for me, and I can feel that it's beating fast. My HR will fall pretty quickly from 150 to around 80 when I stop riding but takes a long time to return to resting. The only thing I can think of is that I have asthma so that could contribute. Or else, maybe this is a normal phenomenon and I shouldn't worry. Any ideas?