There are fitness challenges—and then there are mental crucibles from Gym Jones.

The following 4 tests have been known to make men sweat waterfalls, collapse from exhaustion, speak in tongues, and even weep. But if you have the grit to make it through them, you’ll come out stronger, fitter, and better on the other side. So pick one from the list, put your head down, and just freaking go.

1-Minute Sprint
“A minute might not seem long, but it is if you go hard enough,” says Gym Jones’s Rob MacDonald. “This will reveal how far you’re willing to push yourself. If you’re not crushed at the end, you held back.”

Directions: Hop on a fan bike and try to burn as many calories as possible in 60 seconds. (The bike will display your result.) Average is 45; the Gym Jones record is 89.

2,000-Meter Row
“This is a classic Gym Jones test,” says MacDonald. “When you do circuits for time, you can cheat form and cut corners. This is just you and the computer: no cheating, no shortcuts—just objective feedback staring you right in the face.”

Directions: Program the distance setting on a rowing machine for 2,000 meters. Try to complete the distance in less than 7 minutes.

10-Metre Murder

“This test has you face ‘the moment’—the point in a workout when you either persevere or quit,” says MacDonald.

Directions: Grab a stopwatch and head to a track. Set it for 1 minute and run 10 metre, resting for the time remaining in the minute. Next, run 20 metres, resting for the remainder of the minute. Keep adding 10 metre until you can’t beat the clock. Your goal: 200 meters.

Death by Burpee

“You don’t need a gym or any kind of special equipment to take this test,” says MacDonald. “All you need is a willingness to suffer and a desire to discover what you’re made of.”

Directions: Record the time you take to do 100 burpees, touching your chest to the floor during the pushup and jumping at the end of each rep. Try to finish faster each time you do it (every few weeks).