Your toughness is made up of equal parts persistence and experience. You don't so much outrun your opponents as outlast and outsmart them, and the toughest opponent of all is the one inside your head." - Joe Henderson
but I'm going to ask anyways cause in the little time I have to research, I have yet to find the answer.
I did my first LHR long run yesterday. I'm 39 and I averaged a heart rate for the full run of 138. Every mile (except first mile whre HRM went bizurk) was 141 or under. What I'm wondering is what about when you have a spike in hr like up to 147 or so during that mile. Does that matter? Or does it not as long as you average the target rate for that mile.
Sorry bout the question, just don't have alot of time to find the answer right now.