It might sound odd, but one of the best ways to get stronger, build endurance and – over time – even get faster, is to slow down. No zen provocation here, no fortune cookie wisdom. This is pure physiology. Biomechanics. Heart, lungs, mitochondria. It’s one of those simple truths that’s hard to accept, especially in a culture where everything has to be more, faster, harder. And yet: welcome to zone 2, the not-so-mysterious land of slow running.
What slow running is (and why it works)
Running slow means keeping a pace where you feel relaxed, you’re not gasping for air, and ideally you could carry on a full conversation. You’re not pushing it – in fact, you’re cruising in what’s known as the aerobic zone, also called zone 2.
Zone 2 is the heart rate range where your body works efficiently, mainly using fat as fuel and improving your heart’s ability to pump blood and your muscles’ ability to use oxygen. In plain English: the more time you spend here, the more you turn into an endurance machine. Your running economy improves, your mitochondria multiply, and your heart gets stronger.
Zone 2: a heart thing
To understand zone 2, you first need to know your maximum heart rate (HRmax). The simplest (though often inaccurate) formula is: HRmax = 220 – age
(but if you want a reliable number, get a stress test or use long-term data from your sportwatch).
Zone 2 is typically around 60–70% of your HRmax. If you’re 40, for instance, your estimated HRmax is 180 bpm, which makes zone 2 fall between 108 and 126 bpm.
But does running slow actually help?
Yes, and here’s why:
- You build your aerobic base – the foundation of everything.
- You recover better – zone 2 runs don’t break you down, they build you up.
- You burn fat efficiently, which is also great for your metabolism.
- You lower your injury risk, thanks to the lighter impact and manageable muscle load.
- You train more and better – because you can pile on volume without burning out.
And no, it’s not boring. Or at least it doesn’t have to be. If you’re bored, change your route, your playlist, your shoes – but not the principle.
High, medium, low intensity: what’s the difference?
Think of it this way:
- High intensity (zones 4–5): short, brutal, great for speed.
- Medium intensity (zone 3): the no-man’s-land. Too hard to recover from, too easy to spark real growth.
- Low intensity (zone 2): this is where you lay the groundwork. No foundation, no building. And without a solid base, it all eventually collapses.
The problem? Most runners live in zone 3 because “it’s my comfortable pace.” But that’s exactly where nothing much happens. It’s the gray zone – the one where you feel like you’re working, but you’re really just wearing yourself down.
How to monitor zone 2 (without going crazy)
- Heart rate monitor: the most accurate way. Keeps you in check in real time.
- Feel: if you can talk in full sentences while running, you’re probably in zone 2.
- Nose breathing test: if you can run while breathing only through your nose, you’re likely in the zone (yes, really).
- Paranoia: the first time you run this slow, it’ll feel like you’re doing nothing. Fight the urge to speed up. Trust the process.
Ideal weekly plan with slow runs
- Monday: Rest or yoga/stretching
- Tuesday: Zone 2 run (45–60 min)
- Wednesday: Specific workout (intervals, tempo run)
- Thursday: Zone 2 run (40 min, optional)
- Friday: Rest or light cross-training
- Saturday: Long zone 2 run (up to 90 min or more)
- Sunday: Easy run (zone 2) or active walk
The moral of the story?
Running slow is an act of trust. It’s choosing a path that isn’t always uphill, but that helps you build something solid – your body, your well-being, your endurance. And yes, even your race time.
All it takes is time. But you’re already earning it. Slowly.