Hark, Hearthlight! Walk towards the light of Tabata Method in the darkness of endless cardio. Kite explains briefly why this method is great while you're locked down in this video.
Tabata Method - Cardio gains with 15 min, a couple times a week. Doesn’t require a lot of space and not a lot of equipment.
The method is simple - maximum effort on a particular for minimum amounts of time alternated with short rest periods (typically around 10 sets of work/rest). A starting ratio for beginners is a work period of 15s and a rest period of 40-60s.
As you improve your cardio, you can either increase your worktime or decrease your rest time between sets. For the first several sets you shouldn’t feel gassed, but by about half way through, if you’re not feeling challenged, you should increase your worktime or decrease your rest time.
A note from Kite about work/rest ratios
You'll see the rest time fluctuate for Tabata especially if you google for routines. I find when I am untrained in cardio, I need at least 30 seconds rest time if I'm really doing max effort. This will be different for every skill level and exercise, and as you progress you should lessen your rest time. Just find what works for you and start slow. The "true" protocol of 20 on 10 off was for Olympic athletes.
If you're somewhat trained, try this instead, 20 on 30 off.
What Exercises are GOOD for Tabata?
Body weight exercises
Dumbbells/Kettlebell - goblet squats, kettlebell swings (make sure it’s a low enough weight you can do a high level of intensity the whole time with good technique)
What Exercises are BAD for Tabata?
Things like barbell squats and barbell deadlifts are not recommended because as you tire, these things tend to suffer for technique, and with bad technique you can really hurt yourself.