Interesting! I should try this!
HIIT, when done properly, is actually pretty brutal. I tried it a few times (mostly to improve my oxygen intake) and got some serious muscle/joint ache for my troubles (had to stop all exercise for a month). I'll just stick to my 1+ hours runs which can actually be fairly relaxing/enjoyable with music and audiobooks. If you're enjoying HIIT, you're doing it wrong (or at least not hard enough).
Intense exercise works to get fit, but it doesn't help against the many downsides of a lazy lifestyle.
For example if you have an office job, or sit in front of the TV or PC a lot at home, you are prone to get many different heart diseases due to bad blood circulation.
If you are like me that have both a office job and likes to sit in front of the PC then the first step I'd recommend is to get a desk you can raise and lower so you can stand at work and at home gaming. So look it up with your boss and see if he can get you one for work, and then get one for yourself at home.
If you can't afford one at the moment then be sure get away from the PC fast and walk around for a bit to stimulate the blood circulation between gaming sessions.
When watching movies its easy to just stand up and watch it for a while.
You also burn twice as much calories when standing up compared to sitting down, and its better for the muscles as well.
This is also true for gym workouts as well, its just not enough if you are sitting down and being inactive on your spare time and/or on work. But all exercise is good, so squeese in as many of those intense exercises or gym workouts as you can as well! But the first step to being healthy is all that passive exercise you get throughout the day.
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I do HIIT sometimes, and I disagree, pushing yourself to the limit can be very satisfying and enjoyable sometimes depending on mood. Sure, sometimes when I already feel tired I just want to get done with it and take a shower and rest, but sometimes it feels really nice if you are full of energy.
That said I do enjoy running more than HIIT, being out in nature is nicer. Also ordered a mountain bike yesterday that I'll use to and from work and probably replace most of my running with biking instead.