A 30-minute run at your limit gives you your lactate threshold heart rate
(LTHR). From it, this page calculates five training zones. Test first, then enter your
result below.
A chest strap, if you have one. Optical wrist sensors lag behind
pace changes and jump around in the cold and with sweat.
A flat route without traffic lights, or a 400 m track. No
treadmill: the curved treadmills in the gym in particular show a different pace than
outside.
A watch with a lap button, or your phone with a running app.
Rested legs. No hard training and no leg training the day before,
at most an easy run or a rest day. With tired legs you will not reach your threshold,
and your zones come out too low.
How it works
15 minutes warm-up, easy, with three to four 20-second strides
towards the end.
30 minutes as fast as possible, but even. Imagine a race over
exactly this time. Run alone, not in a group: with others it turns
into a race, and the number is no longer right.
Press the lap button after 10 minutes. The first 10 minutes are the
settling-in phase, your heart rate is still rising there.
Stop after 30 minutes and press the lap button again.
10 minutes cool-down, very easy.
What counts is the average heart rate of the last 20 minutes, the
second lap. That is your LTHR. Also note the distance of the full 30 minutes: it gives
you your threshold pace.
Pacing: the most common mistake
Almost everyone starts too fast, falls apart after 15 minutes and runs the rest too
slowly. Then the number is too low, and so are your zones. The first 5 minutes should
feel hard but controlled, not all-out yet. The last 5 minutes can be
everything you have left. If you cannot speed up at the end, but never had to walk,
your pacing was good.
If you clearly fell apart or stopped on the way, the number is only a lower
bound: your real LTHR is probably higher. Repeat the test in two to three weeks
instead of training with it.
When not to test
With a cold, a fever or after a bad night.
In heat above about 25 °C: your heart rate rises even if you do not run faster.
With cardiovascular complaints, or if you have not trained hard for a long time:
get a medical check first.
2. Calculate your zones
LTHR Threshold pace
Set up the zones on your watch as zones based on lactate threshold, so
the display and the analysis match. Everything is calculated here in your browser and
nothing is sent anywhere. Only your LTHR is remembered, on this device.
3. What to do with them
80/20. About 80 % of your weekly training time belongs in zone 1
and 2, only 20 % in zone 4 and 5. Your Hyrox group sessions are your hard training,
whether you come once or twice a week. Everything you do on top should be easy,
mostly zone 2.
Zone 1 is for warm-up, cool-down and recovery days.
Zone 2 is the base: most of your running belongs here. You can
still speak in full sentences.
Avoid zone 3 as your default. It feels like good training, but it
is too hard to recover from and too easy to make you faster. Run easy runs slower and
hard sessions harder.
Zone 4 is the threshold. Your running pace between the stations in
a Hyrox race is typically just below or inside it.
Zone 5 you rarely need to train separately: you reach it on its
own during burpees, wall balls and sleds.
For running only. On the bike your zones are usually about 10 beats
lower, which needs its own test on the bike.
Retest every 6 to 8 weeks, or when your zones feel wrong in
training.
4. Zone 2: easy is harder than it sounds
Most people run their easy runs too fast and end up in Zone 3. That feels productive, but
it is no longer easy running.
How you know you are in Zone 2
Your heart rate decides, not your pace. Stay inside your Zone 2
numbers from the calculator.
Talk test: you can still speak in full sentences.
Set a heart rate alert on your watch at the top of Zone 2, then
your watch tells you when you drift up.
When your heart rate climbs
Slow down, or walk. Walking uphill is fine. For many people Zone 2
is a mix of running and walking at first, and that is right.
Run alone or with someone at your level. Running with faster
people pulls you out of Zone 2.