When you first start out, you may only be able to go to your maximal exertion for 15 to 20 sec if your really out of shape. Thats fine, do that then take a 30 to 40 sec rest, and go again. As you progress your exertion times will go up, maxing out at around 30 sec. From there you should improve by upping intesity for those 30 seconds.

after 8 weeks of this, switch up and do some medium intensity cardio for 20 to 25 min, 3 or 4 times a week. I would go 3 to 4 weeks with that, then back to hiit for 3 or 4 weeks. This will keep the body guessing until you reach your goal. then you will want to switch up so that you can stay at that new body fat level. when you reach that point we can discuss that aspect.

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I don't do this for my family, my friends, women, accolades, pride, or ego. I do it for me and no one else, its just part of who I am.