what i do is repetitive and it empties my stamina all the way but gives about 4k or more in a certain stat field..
i log in, commit the highest crime, find a couple of people to attack and then i use some burgers to raise my energy..but only to about 50%..then i use one shot of vodka to refill it the rest of the way. that way its 100% energy and only 40-50% fat. i then go to the gym and use all of the turns for workin out a single stat (ie speed)
once the energy is at 0, the fat should be around 0-8% and i use a vodka shot and burgers until im at 100% energy again and then work out for that same stat. i usually have to get lipo once or twice, but thats jus 10 crys..you will keep workin out but you wont be able to get as high an energy cuz the vodka fills up about 50-60% of your energy and by then your BAC should be maxed. but u will eventually wear your stamina all the way down and gain about 4000 stat points.
from there you could refill your stamina cuz it takes the longest to recover and then wait about an hour or whatever it takes to bring down your alcohol level and then do it all again.

plus, taking the classes will increase your stats like crazy..even if it takes 65 days to complete..in 2 months lol you will have some higher stats plus whatever you do before they are done..