You've gotta hustle for the muscle, people.
Such was the valuable lesson passed along to Tonight Show viewers on Monday evening, courtesy of The Fungo Brothers, a pair of workout fiends from decades past who look eerily similar to Dwayne Johnson and Jimmy Fallon.
In a pair of helpful workout videos, mop-topped siblings Jeff and Tad asked folks if they wanna run faster via glutes that are “harder than plaster” and whether they want to feel "burn between the legs."
"If you wanna get packed and stacked, you've gotta Jack it," Jeff said of an invention called The Jack Weight, with Tad adding:
"You've gotta Jack it in the morning. You can Jack it in the afternoon. Oh, god, and then you can even Jack it all night."
Wait... are we still talking about exercise? Watch the sweat-filled footage now: