This is strong work from Howard, and bears repeating: Most people get Zone 2—low-intensity training—very wrong, generally due to terrible advice from other confused people.
Why People Get Zone 2 Very Wrong
Paul: Here is Howard on X, with my annotations. He starts with this conversational gambit:
Too many people get this whole “Zone 2” thing wrong. Very wrong I thought we were beating up the phrase too much many years ago Now, every wannabe health coach is screaming it, too. And most of them have absolutely no clue what they’re talking about. Even many docs selling supplements on IG have no idea. Literally… none.
Paul: Spot on. No matter how overused the phrase is, people continue to get it badly wrong. Let's dive into why.
Low Heart Rate Training Is Important, But Lower Than You Think
Here is Howard again:
Low heart rate (HR) training is important. Just like high HR training is, too. Should we be doing more low-HR training than high-HR training? Yes. A lot more low HR training. But it’s probably at a lower HR than you’re doing now. Much lower. People think their LT1 or AeT is a magical 70-75% of their max HR. (AeT= Aerobic Threshold. LT1= first inflection of lactate) It's not for many. First, most don’t know their true max HR. Calculated max HRs can be way off. Running max HR doesn't = cycling max HR either. Second, if you’re not fit, 70% of your max HR is not your AeT.
Paul: Let's hit the high notes:
- Low HR training is important
- You should do more low-HR training
- You shouldn't only do low-HR training
- You probably have no idea what the right low HR is for you.
Repeat that to yourself until it sinks in. And ban yourself from Insta fitness influencers while you're doing so.
Where Zones Fit In
Back to Howard on what low HR is, and where zones fit in:
HR zones are determined by the physiological changes that occur during them and, thus, by the adaptations we seek to encourage. We determine our HR zones using metrics that reflect these physiological changes that vary as our effort increases. For those who are starting out and want to be healthy... You’ll probably have to walk or hike to be in Zones 1 &2… Either zone is fine… don’t sweat it. It’ll take a lot of training to stay under your AeT and be able to run. Cycling will be a lot easier to stay under your AeT.
Paul: These are key points. Most people struggle to do much of anything at a low HR when running, so they are better off doing jog-walk combos, or just cycling.
Don't Train At Your Aerobic Threshold, Silly
Howard again, on whether you should try to hit your aerobic threshold at the top of Zone 2.
And don’t try to hit your AeT. That’s not the goal of all this! The goal of low HR training is to stay below your AeT… Otherwise, your physiology changes Your AeT is a ceiling… not a goal.
Paul: In short, don't. As Howard says, it's just a fuzzy demarcation line, not to mention one that moves around all the time, so don't think of it as a target, but an upper limit best avoided during low-intensity training.
Yo, I Want to Take This to the Next Level
Finally, what's next if you get this stuff dialed in? Insta fitness influencers?
For those who want to dial things in… you’ll need to have your lactate measured. Your lactate levels during a run or ride will tell you what’s happening from a physiological perspective within your cells. That will determine your HR zones… Not just a percentage of a made up maxHR. Look… I’m not a professional coach… chat with them if you’re that serious ;-)
Paul: Yup, you will need more precision if you want to take it to the next level. Don't eff around with messy heuristics. Get some lab tests done. They aren't that expensive. I have done them, but I didn't start by doing them. I started by focusing on understanding what low intensity really means, doing a shit load of it, and avoiding injury/detraining cycles.
Now, get out there ... at the right heart rates.
