Fastest 10km you can do, but keeping your HR under the 75% range as defined by the Karvonen formula

The idea is to keep the HR steady after the initial rise.
Peeking over the ceiling for short periods is allowed, but the aim to keep just under the max level.

52 and saw 183 doing random bike intervals last week, they were hard but not maximal in a freezing cold garage …it’s almost certainly higher for a planned max hr session.

I think my TR has a few erroneous values. I’d say my max HR last year was 200 - though I’m bit unsure whether or not it would be that high now I’m unfit and a tad out of shape. My max hr always tends to drop.

RHR is 43.

200 for HRmax

200 - 43 = 157 for RHR

[157 x 0.75 (max intensity)] + 43 = about 160 bpm

Is that right, yeah?

That’s kind of the ceiling I look for when I’m going for a really steady low z2 run. So there or thereabouts.

My high hr max gives me a bit of leeway here, luckily.

220 minus would leave me down at 148 where I’d be struggling to run!

So you’ve got a huge range above your z4 then if you’re going up over 200.

I normally class z2 as 150-170 can cruise in high 160s but have to really concentrate/go slow to keep under 160
Z3 is 171 to 182-5 depending on fitness.
Z4 low 180s to low 190s

Solo half would be 183 or so.
Mara would be 181 or so.

Took a look on TP at some easier Aerobic runs I’ve got and pulled fastest 10k and Im around 4:02 for sub-150 so imagine I’ll be around 39:00-40:00 maybe creeping towards 38 if held 152-155 solid on a suitable course:) Course would have a big impact on something like this I feel for how close to average you can hold.

I’ve got 140 to play with which was the number I picked out of thin air last autumn as a relatively comfortable HR, I’d guess I’ll be somewhere around 7:45 miling