I'm not retired yet, trying to lose weight before retiring so that getting health insurance does not become a problem. I go to the gym usually about 4-5 times a week, but when I have had a late night, when I've had too much stress, etc, it gets skipped. I'm thinking that during the first couple of years of FIRE while I am doing the work of landscaping my yet untouched 2 acres, I will probably lose some. And if I have had a late night, I will get up when I get up, and still have plenty of time to get on the treadmill or walk into town and back with DW (4 mile round-trip), or go into the next town on my bicycle (18 mile round-trip), or take a kayak to the lake and paddle for a while, etc. Currently, if I've had a late night and end up getting up too late, my chance for any exercise at all that day is shot.
In essence, I am looking forward to being able to be much more active than I am now. Our California (home) weather is nice enough that I can get lots of outdoor exercise whether by working in the yard or sporty activities, and when the weather is not so nice I can still use the exercise equipment (treadmill, rowing machine and probably an eliptical by that time). For eating, I love to cook, and will be doing lots more cooking at home, using healthier ingredients than I can get here (overseas assignment). I have 50 or so pounds that need to come off, and if I wanted to get to a BMI of 23, then I would have maybe 15-17 more to go beyond that. My goal is to lose at least 30 in the next two or three years before FIRE, and work on the rest over time...maybe three years for the next 20, and two or years for the next 15 to get to that 23 BMI. If I try to do it all at once, I'll have to do some kind of severe diet, that I know won't last (yo-yo back up) and having to buy clothes on the downside, and then have back on the up side. If I do it slowly, over a long time, then my annual clothing budget should cover it and I won't have as much risk of ballooning back up.
R