As for the first question, I think that depends on how well a person has become acclimated to running in the heat. Today, it was 20C (about room temperature) and heart rate was stable. I have been able to stay at a target heart rate before – but I had to reduce pace in the very late stages of one hour or longer runs.

The reasons I chose not want to run with my heart rate monitor during the marathon are:

1. It’s common that people have a high rate at the beginning of races due to being anxious. I know I am one of those people so I did not want to end up slowing down just because my heart rate was high.

2. I was confident in not using heart rate as my guide. I had spent significant time running using a heart rate monitor to know what my marathon pace target heart rate should have felt like. In other words, I felt I did not need it.

Of course, it might have been interesting to wear the monitor and record the data. I’m sure my coach would have liked to see those numbers!

I may do that for the next marathon. We’ll see.

I am also curious to why you choose not to monitor your heart rate during a race. I would think that having collected HR metrics during training it would be valuable to monitor also during a race and adjust the intensity if you hit a HR that you know from collecting metrics previously means “trouble”.

I’d also think HR metrics from a race would add value when determining race strategy for future races?