Running too fast at MAF heart rate

by Michael Groiss
(Huntington Station, NY USA)

When I run at my targeted MAF heart rate, I am not running easy at all. In fact, I would be running at tempo pace. What should I do?

Nicole's reply:

Hi Michael, thanks for your question.

Well you are one of the lucky ones! It sounds like you may already have a very well developed aerobic system. Maybe you have been doing aerobic training for years without realising it.

As you run faster, your aerobic system tries to keep up by providing more and more energy to your muscles. For most people this causes their heart rate to increase above their MAF heart rate (thus increasing metabolic cost), in an attempt to feed the muscles.

However for those people with an already well developed aerobic system, their heart rate can stay at a relatively low rate (minimal metabolic cost) and yet still provide the energy needed to feed those working muscles. In this case the workout feels hard because of the working muscles but yet their heart rate remains low because the aerobic system is very efficient.

Phil Maffetone has written a good article on your situation which you might find interesting. Running at my MAF pace feels too fast