One of the most impactful tools that I have learned over the years is Zone 2 training – both for the physical benefits but also the psychological that can come with it. Adding zone 2 cardio into your training is not particularly intuitive, which is the most likely reason that it isn’t a part of your current program.
What is Zone 2?
In short, zone 2 is a steady state effort/heart rate range that your body responds to in a certain way that does not occur at more difficult intensities. As long as it is a steady state cardio workout, the type of workout is not that important. A quick internet search will bring you a dozen different ways to “calculate” what heart rate range zone 2 is exactly – ranging from percentages of max HR, age-based calculations, fitness testing, or just based on how you feel. The good news is that, for the most part, all of these various calculation methods get you to a fairly similar place. For this reason, I would suggest using a combination of the Maffetone method to set the upper threshold of your zone 2 paired with in-workout adjustments based on how you are feeling in the moment – this adjustment part is important as it will decrease (or even eliminate) your reliance on a HR tracking device. Upper threshold meaning that your HR should not drift above that number during your zone 2 workout.
For a reference, here are the HR zones that I use when training off heart rate. I always use heart rate as my main metric during zone 2 workouts, though I typically use pace for more difficult sessions:
Here is the Maffetone method equation:
To remove all of the math and numbers from the equation – zone 2 is simply a steady state effort level that you could maintain a full conversation without running out of breath while performing that effort. You should feel like you could continue at this pace "all day." Yes, these workouts should be that easy. Don’t be surprised if you almost feel “bad” for not working hard enough during these sessions – that is ok, the point of these workouts is entirely different from something that is more difficult, therefore the point is not for them to be harder. If you are not sure, always err on the lower side of effort level/HR.
What are the benefits of zone 2?
There are many different benefits of training in this zone at a cellular/metabolic level – including things like lowering blood pressure/resting HR, improving mitochondrial function, increasing your ability to use fat as an energy source, and many more. Though, these things are difficult to notice in yourself as you train, but there are many obvious benefits that you will quickly realize:
- Moving at a quicker pace for the same heart rate
- Lower risk of injury since you are not working as hard during these sessions
- Minimal fatigue after these sessions
- Able to do more overall work due to the lower intensity
- Able to maintain your zone 2 pace for longer
Another benefit that is harder to measure is the fact that these workouts are generally relaxing given that they are not done at high effort level. I use this time to listen to podcasts and audiobooks since I am able to focus on them at the lower effort level – this is a good test to make sure that I am staying in zone 2, as soon as I start to space out of what I am listening to or have trouble focusing, it is likely that I need to slow down.
What should you do?
The generally accepted wisdom is that the target should be to get at least 150 minutes per week of work in zone 2 across 3-4 separate sessions. While this may seem like a lot, this does not necessarily have to be purely added work into what you may already do over the course of the average week. Here are some tips for how to get this time into your schedule:
- Use it as a warmup – zone 2 is a great zone to warmup for something more difficult (think 15-60 minutes before lifting, another sport, or starting some more difficult intervals)
- Use it as social time – since your zone 2 pace should be a pace at which you can have a conversation at, you can do this with a friend and talk throughout
- This could also apply to work meetings or any other obligations that you can attend remotely
- For many, you can get into zone 2 by doing a brisk walk, meaning you can get your zone 2 work in with a daily walk
Like I mentioned earlier, the type of exercise that you choose for your zone 2 work is not that important since this is a workout with largely metabolic and functional benefits – any type of cardio works here, including running, walking, swimming, cycling, elliptical, rowing, and more.
The most common challenge that people have with zone 2 work, specifically if you are not doing a lot of cardio to begin with, is finding an effort level that you can maintain without your heart rate crossing over your upper threshold. Especially if you are running, it can prove difficult to run while staying within zone 2. My advice here is to not worry at all about the pace you are running and only watch your heart rate – if that means your zone 2 pace is a brisk walk, that is totally fine and what you should do at first. You will improve quickly and be walking/running faster in no time. You can also do something that is a little easier on the body to keep your HR down like cycling or the elliptical (both of which you will have a generally lower HR at a given effort level).
One last thing that you may be thinking – none of this is specific to endurance athletes like runners or triathletes. Everyone can improve their health by adding more zone 2 work to their program. Though, if you are primarily an endurance athlete, you will get extremely comfortable in this zone as it will make up 70-80% of your total endurance training. For an endurance focused program, this means that a large portion of your work will be done at a much easier effort, but the remaining 20-30% will likely be more difficult than you are used to – polarized training being the goal (lots of low intensity work and some very high intensity).