Originally Posted by rsbob

Did a heavy Zwift session the day before yesterday with an average HR for an hour and a half of 160, staying in threshold and tempo the entire time. Started feeling twinges in my chest which have since stopped. Had the same thing occur when I first got Zwift two years ago and went absolutely crazy pushing myself and ended up getting a EKG and other studies to see if I was damaging myself. All the results came back negative but didn’t like having those minor pains, so backed way off. Looks like running my heart that hard for so long is not a good idea as my body is telling me it is not happy so will moderate my efforts to either decrease duration or effort.