If you read one zone2 tweet: With cardio sports you basically want to train as much as your body can handle ("can handle" is key, if you get injured or get sick too often, or psychologically higher volume means you spend less years in the sport ->your body can't handle that)

Having plenty of your efforts in zone2 lets you train a little more. Maybe you could do 4 hours in a week in zone3, or you could do 6 hours in a week of which 5 are in zone2 and 1 in zone4. 6 hours is probably better than 4 more so zone2 emphasis permits a more productive week

Thats basically it- your better week is caused by more training rather than by zone2 training. If your body can train 10 hours per week but only have time to train 5 hours, train some/plenty at a higher intensity rather than only giving your body 50% of what it can recover from

Zone2 has become this weird magic pill cult type thing from influencers/podcasters and I often hear people who their interest is not in "getting into cycling" its "getting into zone2 cycling". Zone2 or bust mentality because of some koolaid they drank.

If you go talk to an East African runner about how to improve in running- he might never use the word "zone" and yet your favorite podcaster with no real experience/success/credentials has convinced you it is this holy grail.

Niche tweet but so many people end up massively misapplying this. The pros are so good that lots of their easy stuff is actually zone1, we're so bad that we're incapable of staying in zone 2 and compromising to allow some zone3 is better than refusing to do longer/hotter efforts

@SalsaTekila (Probably not worth researching beyond that. But you'll probably start hearing it mentioned more)

@SalsaTekila You'll see sub 3 marathon runners who can't get much above marathon pace in a 5k (and if they ran some 400s twice a week their path to 2:50 would be much easier than talking on an extra 30 miles per week at 10 minute mile pace)