heart rate zones - % or Karvonen?

turbo_hamster

Last winter, when I went to spinning classes, I used the Karvonen formula to work out my heart rate zones (i.e. based on difference between Max HR and resting HR).

However, this year, I am a bit uneasy about using the Karvonen zones, because they are so different from zones based on simple % max. heart rate. My max HR is 179 and resting HR 55bpm, so the actual heart rate zones compare like this:

Simple % of max. HR
50% 90bpm
60% 107bpm
70% 125bpm
80% 143bpm
90% 161bpm

Karvonen formula
50% 117bpm
60% 129bpm
70% 142bpm
80% 154bpm
90% 167bpm

Especially at lower zones, the difference looks very significant. I really don't know which system to use now. Does anyone have an informed view of which system is more beneficial? Is it horses for courses? Does it depend how well trained you are?

Alex_Simmons/RST

What matters is that you work hard enough, for long enough, often enough. The numbers posted don't indicate what element of your fitness the various levels are intended to work on.

What I can say is that anything up ~70% of Max HR is pretty much a waste of time from a fitness development perspective (unless perhaps you are untrained when just about any activity will make you fitter).

If you want to get fitter, then the bulk of you training time will be spent >70% of Max HR and probably should be mostly >75% Max HR.

Here's a quick summary of HR zones I have, based on % of Max HR and aguide as to the typical duration of efforts:

<70% Recovery (up to 90 min)
75-80% - Core endurance (1 to 6 hours)
80-85% - Tempo (30-120 minutes)
85-92.5% - Sub-TT to TT (5-60 minutes)
>92.5% - Maximal Aerobic (2-8 minutes)

I actually have them broken down a bit more than that but from a basic training guide perspective, these are a reasonable compromise between being broad enough to be simple to use and specific enough to be targeting the major physiological elements of aerobic fitness.

Good luck!

turbo_hamster

I think I follow you - the target training zone might be 75-80% of Max HR for someone wanting to build endurance. The same athlete might be given different percentages if using Karvonen formula. I assume that as fitness improves, resting HR declines and so Karvonen figures change.

It sounds as if you recommend using training zones based simply on maximum heart rate. Perhaps I will drop the Karvonen training zones when I go back to the spinning classes.

In the last month or so, I have started using a training zone of 75% to 82.5% of MHR on a 16 mile commute. The intention was to improve basic endurance. I work part time and currently am riding only 4-5 times a week, mostly one-way commutes, plus an each-way commute or a longer, easier ride at the weekend.

My ride to the office begins flat (so I allow a 15 minute warmup) then I ride for 50 minutes on an undulating route at 75-82.5%, and after that, cool down. I am intending to build up the central part of the ride by 5 minutes a week, although I can't build up the ride to be very long, as I do have to get to work, or do the return journey before dark (I am lucky to work part-time with flexible hours).

So it looks, from your information, as if this is an ok way to spend the early winter