Zone 2 training allows for higher training volume compared to very high-intensity training due to lower physiological cost and reduced wear and tear.

“And again, volume drives adaptation. That's the thing to remember. It's volume above all else that's driving adaptation, provided that volume is at least at zone two where you start to um, undergo all those changes we discussed.”

“However, as you progressively increase your training volume, a more varied intensity distribution—including more zone 2 work—becomes beneficial.”