Grand Theft Auto: San Andreas was the first game in the series to turn its protagonist into something close to an RPG character. CJ has a body you actually have to manage: muscle, fat, stamina, lung capacity, and a set of skill stats for driving, shooting and more. Here is how each one works and the fastest way to build it.
Muscle
Muscle is built at any of the three gyms (Ganton in Los Santos, San Fierro, Las Venturas) or out in the world by running, cycling and swimming. On the treadmill or stationary bike, 14 seconds of effort adds about 1% muscle. Out in the world, roughly 150 seconds of running or 100 seconds of swimming or cycling adds 1%. If CJ has no fat left and you stop eating, he slowly burns muscle, so keep him fed once he is lean.
Fat
Fat goes up when you eat and down when you exercise. At fast-food spots (Cluckin' Bell, Burger Shot, Well Stacked Pizza), meals are tiered: a light option adds nothing, while low, medium and high meals add roughly 1%, 2% and 3.5% fat respectively. To burn it, cardio is king: about 1.5% fat per 150 seconds of running, or 2.5% every 14 seconds on a gym machine. A little fat is harmless, but max fat slows CJ down and the gang notices.
Stamina
Stamina controls how long CJ can sprint and swim before tiring. Swimming is the most efficient builder at about 5% per 150 seconds, versus 5% per 300 seconds for running or cycling. The gym machines add roughly 4% per 14 seconds. Max it early and traversal stops being a chore.
Lung capacity
Lung capacity is how long CJ can hold his breath underwater. It grows naturally as you swim underwater, and the single fastest way to max it is to collect all 50 Oysters, which also maxes sex appeal.
Respect and sex appeal
Two social stats round it out. Respect rises as you complete missions and win gang territory, and it controls how many homies you can recruit at once, up to a maximum of seven. Sex appeal is what makes girlfriends easier to date, and it is driven by clothes, haircuts, tattoos and the car you arrive in (lowriders and sports cars give the biggest boost), not by muscle or fat.
Skill stats
Quietly, CJ also levels driving, motorcycle, cycling, flying and gambling skills through use, plus a weapon skill for each gun. Flying skill is unlocked at the Verdant Meadows pilot school and makes aircraft far more controllable.
The fast track
If you want CJ maxed early, the most efficient routine is: swim laps to spike stamina and lung capacity, run or use the bike to convert fat into muscle, eat a high meal whenever muscle gain stalls, and grab the 50 Oysters to finish lung capacity and sex appeal in one pass.
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