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I love the example of HIIT. I discovered it inadvertently 10 years ago when I switched to recreational sprinting as a primary form of exercise. It results in excellent physical conditioning with a minimal time investment (about one hour per week total). Establishing habits is difficult and complex. Finding highly efficient (in time, energy, drudgery, money, etc) ways to achieve a desired outcome is a critically impor…
Any way for lazy people to get started with HIIT without going to a gym?
Yes! One set of jump squats as high and as rapidly as you can do them without pause, until fatigued. Rest two to three days afterwards. Once you get into a habit where you hate to miss a workout, switch to doing burpees instead. You can do this anywhere, including a hotel room, so it minimizes reasons to skip. It is surprising how much this works your cardio as well as strength. You can get super-fit doing this one thing and you only need to do one set per workout. In each workout, focus on doing a few reps more and doing them a bit faster than the previous workout. Just be sure to start slow (maybe 6 reps on your first workout) and never increase by more than 10% of what you did on the previous workout. Never do this two days in a row. You get stronger on your rest days, not your workout days. For high intensity workouts, I find that two days of rest is better than one.