20 lbs. is alot but doable
Is weigh in on day before fight?
If it is follow this technique and you will be ok.
1) buy tub of abolene it opens up your pores and makes you sweat alot more.
2) Apply abolene to chest arm pits, inner thighs, stomach back, face ect
3)Warm up on a bike or treadmill just enough to break a good sweat
4) wrap head in heavy cotton towel,body in heavy cotton towel and then put towel over face while in sauna. Wear only this in sauna
5) sit in sauna in 15-20 min shifts. When out of sauna drink a little bit of lemon juice just to keep mouth from drying out.
6) srap self in cotton robe to stay warm
7) weigh self
8) repeat process
9) when lose weight and weigh in rehydrate with pedia lyte. I drink one ounce per pound lost drink it mixed with water and drink it slow I mix 2 ounces of PL with 4 ounces of water. Also I like to eat something with alot of water/juice in it like watermelon, mango or grapes right after i make weight.
If you follow this you should be ok it may take a while so be prepared but if you do it this way you wont be burnt up from a sauna suit or from running like a madman. YOu will need to rehydrate but that is easier than trying to regain energy lost running.
I usually get a massage in between sauna sessions by someone just to stay a little loose and relaxed but that is just me maybe like a 5 minute massage or something like that. I have lost 20 lbs. do this technique over a 8 hour time span and was fully recovered shortly after the weigh in it is a slow and gradual technique but it works better than most.