I'm the rebel here. I started at 252 (CW is 193) at 6' 1/2". I've always been very active (but still got fat). I just walked to begin with because it is very easy to get injured when fat. I didn't wait very long though tell I tried easy jogging and only 3xweek. The problem with exercise is that it will increase your appetite and you may eat back all the calories and then some and it will make you gain muscle (the latter isn't a problem but will make it seem like your not losing fat when you actually are). The gaining muscle can last a couple of months and a lot of people will stall for a couple of months and that will freak them out even though they are losing fat and gaining muscle so they don't see a change in weight and quit. There is also the stress hormones that will be elevated that might make you stall a little bit also.

But if a person is able to get through the stall and is able to burn more calories in than they eat back, they will lose (and feel better and get stronger). I am running 3xweek now and burn about 900kcals each time I go. With that much burned, I don't eat that much back since I have a short eating window so I think it benefits me a lot. If I was only exercising a little, it might make eat back more than the amount of exercise I'm doing and could therefore slow things down.

Sometimes the fasted way to a a place isn't a straight line though. You might be able to get in much better physical shape by not exercising now, get thin, then exercise without the risk of injury and you might get farther ahead in the long run taking that route.

I really like exercising though so I just went for it and it may have slowed me down but that is what I enjoy and I didn't worry about the temporary stall. If you decide to exercise just be very careful and go slow and expect to see stalls for awhile.

With 100-lbs to lose, I think if you do exercise to take it very easy and then when your maybe 50 over you could probably go at it more intensely. Read Jim's posts he started at 360+ I believe and didn't start running tell he had lost a lot of weight and he had great success. I think there are positive and negative going both ways.

I advocate not worrying about exercise up front.
You need to master your diet and new way of eating first. When you are on a roll, losing weight in a sustained way, consistently able to get through your OMAD day, then start walking, and build slowly from there. Remember exercise has virtually nothing to do with weight loss. I'd give omad six months before starting any kind of exercise beyond walking.

I think it depends on your body is telling you. too much working out might give you the munchies and tempt you to splurge. others might be fine, watch the scale and see how it affects your progress. I am going to wait to do workouts til I lost most of my weight just fasting. I have bad arthritis in my hips and knees, so I want to be lighter first, so i don't stress them too much.