Just as in Aesop’s fable, going slow might be the fastest option. Zone 2 training has been all the rage in endurance circles ever since being popularised by Dr Iñigo San Millán in his work with professional cyclists. It’s hard to argue with the stellar success he has had with Tadej Pogačar and other riders in his UAE squad. It might seem counterintuitive that such a low-intensity workout can yield significant benefits, but the science behind it is convincing.

What is Zone 2 training?

Truth be told, low-intensity training is nothing new. World-class endurance athletes have been performing most of their training at low intensities for decades. It just isn’t possible to train for 30 hours per week at higher intensities. At long last, the concept has gained popularity in amateur athletes too.

One problem is that scientists are still arguing about the exact definition of Zone 2. But for amateurs like you and me who don’t own a lactate metre, Zone 2 training means working out within a specific heart rate zone, usually 60-70% of your maximum heart rate. Imagine a pace or effort where you can feel you are working but still easy enough to chat without huffing and puffing. That’s Zone 2! Here, your body optimises fat burning and boosts aerobic efficiency. You are training your body to release energy by burning fat and carbohydrates with the help of oxygen.

Get in the zone

To find your Zone 2 heart rate, use the age-predicted maximal heart rate (APMHR) method. Simply subtract your age in years from 220 to get an estimate of your HRmax. Once you have your HRmax, find the 60 - 70% range of that number to estimate your Zone 2. The APMHR method isn’t the most accurate, but should be a good enough starting point for most. Another method to try is the MAF 180 Formula which enables athletes to find the ideal maximum aerobic heart rate below which to base all aerobic training. 

No tech? No problem! Use Ratings of Perceived Exertion (RPE) to quantify your effort. I prefer the 10-point modification for ease of understanding. On this scale, Zone 2 is an effort intensity of 3 or 4 where 10 is a lung-busting maximal sprint. 

Remember: Zone 2 is a comfortable pace. Going slow enough to keep your heart-rate from overshooting is trickier than it sounds. You may need to walk the hills on your runs, or use really easy gears on your bike. Don’t worry about anyone overtaking you, be the tortoise, and trust the process.

Benefits of Zone 2 training

• Improved endurance: Consistent Zone 2 training can skyrocket your aerobic capacity, making longer workouts feel like a breeze. In most races, it’s all about fatigue resistance. Better endurance can leave you fresher for the moments that count.
• Enhanced fat metabolism: In Zone 2, your body becomes a fat-burning machine, great for endurance athletes and anyone looking to improve metabolic health.
• Recovery and injury prevention: These workouts are gentler on the body, helping you recover and avoid pesky overuse injuries.
• Health benefits: Regular Zone 2 training is a heart health hero, while also improving insulin sensitivity and supporting overall metabolic function.
• Reduced intimidation: For many, the idea of exhaustive, high-intensity exercise is too much to stomach. Zone 2 training promises torture-free exercise sessions.

Kipchoge's secret to success?

It's hard to believe that going slow can make you fast, but if it works for the greatest marathon runner of all time, it might just work for you. Eliud Kipchoge spends most of his training (around 85% of his time) in Zone 1 and 2. Only about 15% of his training is in Zones 3 or higher. 

Specifically, Kipchoge usually only does two key workouts per week that incorporate work above zone 2:

• A Tuesday track session comprising 15 km worth of intervals at around his goal marathon pace of 2:55 per km (!). This includes workouts like 15x1km with 90 seconds rest, averaging 2:50-2:55 per km. 
• A Thursday long run that builds to a fast finishing pace, but still keeping most of the run in Zone 2. 

The rest of Kipchoge's training during the week comprises very easy Zone 1 runs ranging from 4:00-5:00 per km pace. This allows him to recover properly and perform well in his key high-intensity sessions. 

If those pace numbers boggle your mind, remember that Kipchoge’s Zone 2 pace is a flat-out sprint for just about everyone else. But he got there through years and years of consistent training at low intensity, mixed with less frequent high-intensity efforts.

What’s the catch?

While Zone 2 training offers impressive benefits, it requires a significant investment of time. To truly reap the rewards, you need to build towards longer, consistent sessions totalling at least 3 or 4 hours per week. If you’re pressed for time and can't dedicate 45-60 minutes multiple times a week, High-Intensity Interval Training (HIIT) might be a better fit for you. HIIT can deliver significant fitness gains in shorter bursts, making it ideal for those with a tight schedule. However, if you can carve out the time, Zone 2 training is a fantastic and pain-free way to build endurance, boost fat metabolism, and enhance overall health.

Conclusion

Zone 2 training is a revelation for anyone looking to enhance their endurance, boost fat metabolism, and improve overall health without gruelling high-intensity workouts. By dedicating a few hours each week to this low-intensity approach, you can achieve remarkable results, just like elite athletes such as Eliud Kipchoge. Whether you’re a seasoned athlete or a fitness newbie, embracing the art of going slow can pave the way to getting faster. So why not try it? Lace up your shoes, find your zone, and experience the transformative power of Zone 2. The tortoise really can win the race!