While 92lbs in 6 weeks is certainly hard to believe, such high weight gain are not unheard of in the bodybuilding world. What happen is that a guy has been dieting hard for 12-16 weeks plus he severely dehydrates himself prior to getting on stage. Diuretic use can lead to loss of 5-10lbs of water and that is somewhat conservative.
So right off the bat we have a dehydrated guy who lost 10lbs of water, cuh weight is easily gained within one or two days of normal eating and drinking. PLUS after diuretic use the body has a tendency to rebound (overcompensate by storing more water than it was prior to diuretic use). A competitor I know gained 35lbs in 7 days after his last show (I was there at the weigh-in and then weighted him myself 7 days after). NOW, keep in mind that some (most) of that is a water rebound. But we must also consider a glycogen surcompensation... if a guy has been dieting strictly using a low-carbs approach it's not unheard of to see large gains in bodyweight simply due to an increased glycogen storage. The normal body can store around 3g of carbs per pound of bodyweight ... so for a 200lbs individual that comes up to 600g (or almost 1.5lbs of carbs). Then understand that to be stored in the muscles, 1g of carbs requires 2.7g of water (we'll round it up to 3g). So our 1.5lbs of stored carbs come up to 6lbs of bodyweight once intramuscular water is factored in. Now, that is under normal circumstances. After a carb depletion period as short as 3 days the body upregulates its capacity to store glycogen by at least 50% (in some extreme cases closer to 100%). So a carb depleted bodybuilder (almost 0g of glycogen in his muscles) could gain up to 12lbs of bodyweight simply by carb-loading. Those who followed a cyclical ketogenic diet (e.g. bodyopus, anabolic diet, etc.) know that it is quite possible to gain 10-15lbs of bodyweight between friday evening (fully carb depleted after 5 days of low-carbs and high volume training) and sunday evening (fully carb loaded after 2 days of a super-high carb intake).
Ok, that was a bit confusing. So let's make this simple. Let's say that DJ (who competes at arounf 260lbs) decides to carb deplete and dehydrate himself for his bet with his friend. Just be depleting his glycogen stores he could loose around 800g (1.7lbs) of carbs plus around 4lbs of intramuscular water weight.
So from 260lbs he is now down to 254lbs.
Then he dehydrate himself with diuretic and a decreased water intake. This could lead to a loss of aroound 10 more lbs.
So from 260 he is now down to 244lbs.
After he weight-in for his bet he goes on consuming a hefty amount of sodium-ladden food (which increase water retention) and as many carbs as he can stomach. It's fair to say that within 3 days his carbs stores will be filled up and surcompensated. So a 9-12lbs gain in bodyweight (the 6lbs he would normally store, plus 50-100% more as surcompensation).
From 244lbs he is now up to 256lbs (+12lbs)
From the water rebound we can expect a 15-20lbs gain easy, especially if a ton of sodium is consumed.
So from 244lbs he is up to 271-276lbs (+27-32lbs).
Now, a man of his weight probably has a metabolic rate that uses up around 2300kcals/day (accordning to the Harris-Benedict formula). Since he is probably active we must factor in his activity level, let' s say moderate (x1.6) ... so his daily caloric expenditure is probably around 3600kcals/day.
There is around 3500kcals in one pound of fat. So by consuming around 7000kcals/day it would not be out of the ordinary to gain close to 1lbs per day... at least for the first 2-3 weeks. Since he is training and using anabolic aids, it's fair to say that the 1lbs/day might be half fat, half muscle.
So over 3 weeks of gross overeating it would be possible to gain 12-15lbs.
So from 244lbs he is up to 283-291lbs (+39-47lbs)
Now, let's say that he decided to use hefty doses of anadrol or dianabol which lead to a rapid fluid retention, an additional 5lbs of water is not unrealistic.
So from 244lbs he is up to 288-296lbs (+44-52lbs)
This is still a long shot away from 90lbs, but it goes to show that nothing is impossible.
