What is zone 2? How to find your easy pace

You buy a heart rate watch. It splits your training into five coloured bands, it congratulates you on time in zone 2, and suddenly the easy jog is not a jog any more but a test you can fail. Then you read that zone 2 should feel gentle and hear on a podcast that it should feel fairly tough. Your friend tells you he sits in zone 2 at a pace where you would be running for your life.

All three can be right. That is the whole problem, and it is why this page starts with the models rather than with a number.

What zone 2 actually is

Behind every zone model sits the same reality: your body changes gear gradually as the effort rises. At low intensity almost all of the energy demand is met aerobically, meaning with oxygen, and a large share of the fuel comes from fat. The harder you work, the more the fast oxygen-free processes take over, and lactate starts building faster than your body can clear it.

Zone 2 in the physiological sense is the highest work rate at which that balance still holds. In a laboratory it usually corresponds to a blood lactate sitting steady at or below 2 mmol per litre. The key word is steady. It is not that lactate is zero, but that it does not climb while you carry on at the same pace.

The practical value of that level is that you can stay there for a long time without burning yourself out. That makes it the one intensity where an adult with a job, children and a body that remembers old niggles can accumulate volume week after week without breaking down.

Why everyone quotes a different number

This is where the confusion lives, and almost no article says it plainly: "zone 2" is not a physiological term but a position in a table. There are several tables. They number things differently.

So when the podcast says zone 2 should feel fairly demanding, it is probably talking about the three-zone model, where the middle band sits close to threshold. When your watch says zone 2, it almost always means the easy band in the five-zone model. Two different things wearing the same name.

The practical conclusion: care less about the number and more about the description. In this guide, as everywhere else at Operatör 45, zone 2 always means easy, conversational, below the first threshold.

How to work out your zone 2

The usual method is to estimate maximum heart rate from your age and then take a share of it. That works, with one important caveat we will come to.

The formula 220 minus your age is the most widespread. It has weak scientific backing and tends to be wide of the mark for older adults. A better estimate comes from Tanaka and colleagues, who in 2001 pooled data from several hundred studies and close to 19,000 people:

Look at those numbers and notice whether they feel low. They do for almost everyone. A 50-year-old jogging at 118 beats struggles to believe that is enough. That reaction is exactly why most easy runs are not easy.

The caveat: an age formula describes an average, not you. Two people the same age can have maximum heart rates that differ by ten beats or more, and that says nothing about their fitness. Treat the table as a starting guess, not as a verdict.

The talk test beats the number

There is a test that needs no battery, never needs calibrating and tracks your day-to-day form automatically. You say a full sentence out loud while you run.

• Full sentence, unhurried, you could carry on talking: you are in the right place.
• The sentence comes out but you have to break it in the middle to breathe: you are at the top edge. Ease off a notch.
• Only a few words at a time: you are above threshold. That is not zone 2, whatever the watch says.
• You could sing: possibly too easy, but that is not a problem. Nobody gets injured running too slowly.

The talk test is not a makeshift solution for people without a watch. It has been studied against laboratory measures and in practice lands near the first ventilatory threshold, roughly the point where breathing starts to run away from you. That is the same region where zone 2 ends. A method you can use on every single run, for free, is also worth more than a precise method you use once a year.

This is the same test that governs every jogging session in the guide to starting to run after 40 and in the eight-week plan to 5K. So zone 2 is not something new you have to learn. It is a name for the pace you are already training at.

When zone 2 means walking

Here comes the part that is usually missing, and that matters most if you are making a comeback at 45.

If you have been sedentary for a few years, your conversational pace often sits below the slowest jog you can physically manage. Your body simply cannot jog as slowly as your fitness requires. The result is that every "easy" jog is really a moderately hard session, you end up more tired than you should be, and you wonder why it never starts to feel easier.

The answer is not to push through. It is to walk.

• Walk-jog intervals keep you in the right zone while the mechanics adapt. Jog until your breathing starts to run away, walk until it settles, jog again.
• Walk the hills. A climb lifts your heart rate by twenty beats without you doing anything wrong. Walking up and jogging on at the top is exactly what experienced runners do.
• Let the walking share shrink by itself. After a few weeks you notice you can jog longer before your breathing changes. That is fitness arriving, measured in reality rather than in numbers.

Walking in order to hold the right intensity is an active choice, not a mark against you. Someone who walks to stay in the right place is training more correctly than someone who jogs to avoid walking.

Why your heart rate climbs at the same pace

You hold the same speed all the way through, but after half an hour the watch reads ten beats higher than at the start. You have not lost fitness in an hour. It is called cardiovascular drift.

As you heat up, your body sends more blood towards the skin to cool you, and you lose fluid. Your heart then has less volume to work with per beat and compensates by beating more often to deliver the same oxygen. Same work, higher heart rate.

It is normal. There is nothing wrong with you, and you do not need to slow to a walk chasing the number back down. Here is how to handle it:

• Judge the session on the first half, before drift has set in.
• In heat, high humidity or after poor sleep: expect a higher heart rate at the same pace and drop the speed by feel.
• Use the talk test as the referee mid-run. If you can still talk you are in the right place, whatever the display claims.
• Drift becomes more pronounced the longer the run. Once your long runs pass an hour, fluid starts to matter in earnest, which the guide on how to run a half marathon covers.

Wrist measurement has its own sources of error too: cold skin, a loose strap and tattoos can all produce readings that jump or stick. A chest strap is steadier if you are serious about training by numbers.

Heart rate during the session is only half of what your watch can tell you. The other half is heart rate variability at rest in the morning, which reflects how well your body has absorbed what you have already done. The two do not compete. Zones decide how hard you run today, while HRV helps you decide whether today should be a hard day at all.

How much zone 2 do you need?

Less than the internet implies. The usual reference point comes from research by Stephen Seiler, who measured how elite endurance athletes actually distributed their training. The pattern was strikingly consistent across running, cycling, rowing and cross-country skiing: roughly eight sessions in ten sat at low intensity, and the rest were clearly hard. Very little sat in the middle.

Two things matter about that figure. It describes what the elite did; it is not a prescription for everyone. And it counts sessions, not minutes.

For you, training three or four times a week, it comes out simple:

• Run everything easy until you have three months of consistent training behind you. At that point it is the foundation that holds, not the speed.
• Then add one session a week with faster stretches in it. One, not two. What that session should look like is covered in the guide to interval training.
• Keep the rest genuinely easy. That is almost always where it goes wrong: the easy runs creep up to moderate, the hard run drops to moderate, and everything lands in the middle where it costs a lot and gives little.

Counted in time it goes further than most people think. The recommendation for adults is 150 to 300 minutes of moderate intensity activity a week. Easy jogging sits inside that range, and walking counts too. How to gather those minutes when the diary is full is covered in the guide to training when you have no time.

That recommendation has a second half almost everyone forgets: muscle-strengthening work covering the major muscle groups on at least two days a week. Easy running does not cover it, however many minutes you gather. A week-by-week schedule that meets it with bodyweight work at home is in the guide to strength training at home.

Five mistakes that ruin zone 2

1. You chase the number uphill. Undulating ground makes your heart rate uneven. Judge the whole session, not individual minutes.
2. You trust a formula you have never calibrated. If the table says 118 but you can talk comfortably at 128, it is the formula that is wrong, not you.
3. You check the watch every thirty seconds. That turns the run into an exam. Turn the display away and look afterwards.
4. You refuse to walk. See the section above. Walking is the tool that makes easy training possible early on.
5. You run every session at the top edge. An easy run that sits permanently at 70 per cent is not easy in practice. Let one session a week sit properly below.

If you take medication that affects your heart rate

Beta blockers lower your heart rate both at rest and under effort. That means age-based zones stop working: you can be working perfectly correctly and still never reach "your" zone 2, because the numbers were calculated for a maximum heart rate you no longer have. Some other heart medicines affect the heart rate response in similar ways.

In that case, train by perceived effort and the talk test rather than by numbers. Research on that group points the same way: your sense of effort holds up even when heart rate is blunted. If your doctor or physiotherapist has given you specific exercise advice, that takes precedence over everything written here.

When to seek medical advice

• Call emergency services immediately: crushing or severe chest pain that does not ease within a few minutes of rest, particularly alongside breathlessness, cold sweats, nausea or feeling faint.
• Contact a doctor promptly: a heart rate that races, skips or feels irregular during light effort, or breathlessness that is clearly out of proportion to the pace.
• Contact a doctor promptly: dizziness or feeling faint in connection with exercise.
• Check before you start: if you have known cardiovascular disease, take medication regularly or have been completely inactive for a long time.

This is general health information, not a diagnosis or personal medical advice. If you are unsure, speak to your GP or your local health service.

Frequently asked questions

What heart rate is zone 2?

Roughly 60 to 70 per cent of your maximum heart rate in the five-zone model that watches use. For a 50-year-old with an estimated maximum of 173, that lands around 104 to 121 beats per minute. The range is a starting guess, because two people the same age can have maximum heart rates that differ by ten beats or more.

How do I know I am in zone 2 without a heart rate monitor?

Say a full sentence out loud while you run. If it comes out unhurried you are in the right place. If you have to break the sentence in the middle to breathe you are just above. If only a few words come at a time you are clearly over threshold. The talk test tracks your day-to-day form automatically, which no formula does.

Why does zone 2 feel so slow?

Because it is slow, and because it is meant to be. Almost everyone starting out underestimates how little effort aerobic training requires. The feeling that it ought to hurt more is a habit from school PE lessons, not a sign that you are doing it wrong.

Is it okay to walk in order to stay in zone 2?

Yes, and early on it is often the only way. Many people making a comeback cannot jog slowly enough for their current fitness. Walk-jog intervals and walking the hills keep you at the right intensity while your fitness catches up.

Why does my heart rate rise when I hold the same pace?

It is called cardiovascular drift. As you heat up, more blood is sent towards the skin for cooling and you lose fluid, so your heart beats more often to deliver the same oxygen at the same workload. It is normal, especially in heat and on longer runs. Judge the session on the first half.

How many of my sessions should be in zone 2?

Most of them. If you train three times a week, one session containing faster stretches is plenty. Add that session only after a few months of consistent base work. The commonest error is not too little speed but every session landing in the middle, where it costs a lot and gives little.