Avit - I'm not slagging off the Maffetone Theory, I'm just saying it's far too simplistic (maybe that's a better word than generic).
I acknowledge that if I did the bulk of my aerobic training at below 139bpm, that I would still be getting some benefit from that, and would eventually get quicker.
However, it definitely would not be maximal results, as I get more benefit from not using a formula that applies to everyone, and using a calculation based on my body, my heart rate, and my current level of fitness.
I'm not suggesting everyone has to be so scientific about it, and for a long time I used to use the following non scientific / non heart rate based measures:
- A recovery run is run at a pace where you could sing out loud, in tune, whilst you were running.
- An easy run is one where you can talk in full sentences without having to pause for breath.
- A steady run is one where you can still talk normally, but only in shortened sentences.
- A tempo / threshold run has you speaking 2-3 words at a time, in between deep breaths.