Max weight loss so far off one guy is 35kg and counting. Though he has pretty much stopped trying to loose weight per say, but also put muscle on and loose fat.
Lady is a couple of kg’s off 30kg.
Most loose either 0.5kg to 1kg per wk.
Sometimes a bit more.
A few a generally pretty Lazy, they grew thinking Exercise isnt cool and muscles are ugly - that type, but then they realize they need to exercises now. Old habits die hard. Still, they are loosing kg’s, but somewhat slower. maybe 1kg per month of Solid loss? That would be the lowest.
Some dont need to loose weight, like 56kg females, just loose a few kgs of fat and gain a few kgs of muscles. They tend to yo-yo throughout the year depending on when Concerts or parties etc are on. But they keep coming back and are happy as.
Fitness wise, as an eg. One guy, his estimated Vo2 max was around 17.5 when he started. Yes, thats stupidly low, but he was also one very very unfit dude. So unfit, i still remember his very 1st Workout, an easy Med ball workout and he died after 1.5sets… His vo2 is now around 48 and has a low Hr of 43 and is becoming rather Fit and strong.
Chicks, An eg, one starting doing around 12 push ups on her knees only. Now she can do over 20 full ones one her toes.