Zone 2 is one of the 5 [[Heart Rate Zones]], around 60-to-70% of your maximum heart rate. It's associated with the ability to continue to hold conversations, and to avoid [[Mouth Breathing]]. It's where body is more predisposed to burn _fat_ as opposed to glucose. > [!tip] Zone 2, for you > ~133 bpm to ~146 bpm But, according to Dr. Peter Attia, a _more accurate_ method is using rate of perceived exertion. **The talk test** was a better indicator of being "in the zone" than was a heart rate. > [!tip] The Talk Test > You should be _able_ to talk, but not really _want to_ talk. You may also be able to use "the most I can do while only [[Mouth Breathing|Nasal Breathing]]". # Effects Zone 2 (and the upper and lower halves of zones 1 & 3) are where the [[mitochondria]] will increase in number. Higher mitochondrial density means you have more energy producers producing more energy per volume of input (in this case "input" is heart rate, carb stores, etc). Dr. Attia uses a pyramid analogy. If you want a high [[VO2 Max]] (which is associated with lowered mortality), you have to build a wide base. ![[Pasted image 20250323100253.png|350]] Zone 2 cardiovascular training is all the rage right now. It's also possible that it's _always_ been important and I'm only just now seeing it everywhere due to the [[Baader-Meinhof Phenomenon]]. [[Recommended Cardiovascular Training]] would included [[HIIT]] or other types of high heart rate training, too. You shouldn't _**just**_ do zone 2 if you want maximum [[Healthspan vs Lifespan|healthspan]] impact. # Training There are lots of recommended ways to do Zone 2, each of which may or may not work for any given individual. I've never had any proper testing, so I have no _great_ way to know whether I'm _actually_ in Zone 2 or if it's just what my [[Apple Watch]] says... but I've found these methods effective: - Walking as fast as I can outside - Walking on an inclined treadmill - My exercise bike That's it. I've never managed a jog slow enough to be zone 2. That's a goal of mine. Things I'd like to try: - Rucking - Swimming - Stair stepping > [!warning] [[Minimum Effective Dose]] Raises with Capability > As you become more fit, you're minimum effective dose goes from 2 ~30 minute sessions up to a cumulative ~3 hours of zone 2, spread among 3 or 4 sessions. **** # More ## Source - [[Huberman Labs]] - [This video](https://youtu.be/i9AjG5hV1Fw?si=85QtJQ4zpB-SIHxW), re: mitochondrial density - [[Good Energy (book)]] ## Related - [[Huberman's Foundational Fitness Routine]] - [[Heart Rate Zones]]