As I've posted before I've completed W7R1 but am very slow. I have read that one shouldn't exceed a heart rate of 220-age which for me is 159. I think I could increase my pace but am trying to keep to 159 bpm so when I exceed 159 I slow down until I get bpm down. I'd really appreciate the advice/thoughts of others on this matter. By the way, I don't have any heart problems and have no history of heart disease in the family.