I had to edit the title to fit the HN character limit, hopefully I got the gist of it.

One of the researchers tweeted:

"Pretty much the whole industry (incl. @Google Fit @Apple Fitness+) assume that 1 minute of vigorous activity = 2 minutes of moderate activity, in terms of heart health value. Our UK Biobank analyses show that they may be far off, e.g. 1 minute of vigorous = 9.4 minutes of moderate = 94 minutes of light intensity activities, in terms fo type 2 diabetes risk. 1 min of vigorous = 7.8 mins of moderate = 73 minutes of light, in terms of CVD risk."

https://x.com/M_Stamatakis/status/1975783367577838072

Yes, you really only need to do some Tabata to keep your exercise quotient in a healthy range. It won't build marathon level cardio, nor muscle, but it will keep your cardiovascular system and body reasonably healthy for small time investment.

Go so hard that you can't have a conversation and are in around 80% of HR max.

I think walking, and low intense ex is good for things like mental, reflection, etc. General refreshing. But if you need to get exercise in but dislike it, or don't have the time, HIIT is gooooood. :)

Zwift is an excellent way to have fun getting vigorous exercise. If only it didn't cost so much.