Peter Attia· MD
If you know your true zone 2 by lactate testing (highest output keeping lactate below about 1.7-1.9 mM) you can take the perceived exertion + HR anywhere.
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If you know your true zone 2 by lactate testing (highest output keeping lactate below about 1.7-1.9 mM) you can take the perceived exertion + HR anywhere.
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so anytime you're undergoing cellular respiration your body is basically converting glucose or fatty acids into atp and that process can be done very efficiently with oxygen but as the demand for atp which is energy gets higher and higher and higher your body has to start making trade-offs and it has to start going quicker than it would like to and not just utilize the mitochondria and doing this process outside of the mitochondria and in doing so one of the byproducts of that is lactate so we use lactate as a proxy for any time your body is exceeding the capacity of the mitochondria and once you exceed about 2 millimole of lactate which is not a very high amount certainly higher than you are at rest but nowhere near what you would be exerting when you do an all-out effort you have sort of exceeded the threshold of the mitochondria to stay in an equilibrium where it can clear the amount of lactate it produces so that's how i define zone two
zone two is that all day pace lactate has to be below two millimolar you have to be this is a pace you should be able to hold all day
W which is what is the maximum output you can sustain while still exclusively utilizing uh your Aerobic System so therefore you're not at all accumulating lactate um and again I'm being a little a little bit um uh sloppy in my terminology there and we can maybe clear that up a bit a bit later but but basically you know what's the maximum output you can sustain without accumulating net lactate
when we talk about Zone 2 we are not talking about the same Zone 2 that shows up on your Polar heart rate or your Apple watch or whatever other device you're talking about we're talking about um a very specific mitochondrial level of Zone 2 and it's it's it's referring to an um the highest level of work that you can do while keeping lactate at effectively in indefinite steady state which for most people tends to be below 2 Millo
zone two training involves exercising at a moderate intensity it's a steady state type of lactate threshold training