The act of farting until you're unable to. Can be improved upon and used in competition with other fartmaxxers.
Teacher: "Chad stop fartmaxxing in my classroom, you're going to fucking die!"
Chad: "Just ermf, one more eugh, fart."
Fartmaxxing is when you fart so much that your ass checks start gaining muscle
Bro! You should try fartmaxxing
edging a fart on the rim of your ass to increase rectum capacity, this improves the sound of farts and the strength of your rectum
“hey did you see the game last night”
“nah i was too focused on my boy fartmaxxing”
“damn he must have a strong rectum”