Cardio

VO2 Max

VO2 Max (volume oxygen max, or maximal oxygen consumption). VO2 Max is highly correlated with longevity, apparently more so than any other health metric known so far.

Zones

Max heart rate is the highest heart rate you can achieve. The formula to estimate it is $220-\text{age}$.

Heart rate zones are percentage ranges of your max heart rate:

1. Zone 1 — 50-60% of max heart rate.
   • You’ll hit this when walking.
2. Zone 2 — 60-70% of max heart rate.
   • You can pass the talk test and speak in full sentences without gasping for breath.
   • You would typically spend most of your time in this zone.
3. Zone 3 — 70-80% of max heart rate.
4. Zone 4 — 80-90% of max heart rate.
   • You can say a couple of words, but are not dying.
5. Zone 5 — 90-100% of max heart rate.

Interval Training

HIIT (high intensity interval training) is about alternating between high and low intensity recovery segments in your runs. For some reason, the stress this exerts on the heart is extremely beneficial for increasing your VO2 max.

Typical structure of a run including HIIT:

1. Warm-up in zone 1 for 5 mins.
2. 10 sets of intervals where you sprint for 30 seconds, then recover for 60 seconds at a slower pace.
3. Cool-down in zone 1 for 5 mins.