In a public park, we circle Jason Grothe (F3 nickname: Ringer), who has promised to make our lives miserable for the next 45 minutes. He will grunt and groan alongside us-a core principle of F3 is that the rotating volunteer leaders running workouts also suffer.

Ringers playlist starts with Frankie Goes to Hollywoods Relax, and as the first notes sound, were doing jumping jacks. Burpee box jumps and planks follow. Sweat darkens the concrete under a 58-year-old nicknamed Honey Pot, because hes a beekeeper, and steam pours off a 36-year-old nicknamed Sheldon. Dont cheat the man in the mirror, someone says. Sucking wind, I dont respond. Doing so would be disingenuous: Im thinking unkind thoughts about Ringer.

What is F3?

Men across the country are clamoring to be this miserable, with an estimated 20,000 active participants. Think of it as a hyper-positive Fight Club and hipper YMCA. It gives you up to 15 supportive guys in every workout. To join, just log on to the organization's website , find one of the 1,500 free F3 workouts going on in 30 states every morning, and show up ready to sweat in pursuit of conditioning and community. The workouts are usually boot-camp style (reflecting the military background of one of its cofounders), and they happen outside, rain or shine. Occasionally, cinder blocks, kettlebells, or rucks are on the menu; most often, its just you versus your body weight.

David Redding (a former Green Beret) and Tim Whitmire (a former journalist) created F3 eight years ago, when their group workout class became too crowded. Redding used military terms for exercises and hoped to see ten men on that morning, January 1, 2011. But after theyd emailed friends to join them for morning burners, 35 guys showed up to the parking lot of a Charlotte, North Carolina, middle school.

F3 quickly became about more than fitness-the other two Fs stand for fellowship and faith.

Whitmire and Redding attended the same Episcopalian church for years but barely knew each other before they started training together. Redding, Whitmire, and other F3 men I talked to realize that having the third F stand for faith will make some skeptical. They insist that the point is not what you believe in, as long as you believe in something beyond yourself.All men, regardless of religious beliefs, are welcome. During six workouts in multiple locations, I hear no proselytizing.

How F3 Makes Better Men

Redding and Whitmire discovered F3 solved two problems-a lack of deep relationships among men and the abdication of leadership roles by men-that they werent initially looking to solve. The group is all men, but it does more than get men in shape. The fact that its all guys feels like a throwback while also offering a different dynamic. ( Theres also F3 for women, FIA .)

Redding believes men think their relationships and friendships cant withstand deeper reflection. F3 releases them from what he calls sad-clown bondage-a Sopranos reference to being happy on the outside, sad on the inside-giving them an instant network of brothers in sweat. It delivers quality guy time, letting men focus on one another.

View this post on Instagram Has any PAX conquered that tower behind the group? #repost @f3_knoxville Best way to enjoy Worlds Fair Park is before most people have had their first cup of coffee! #ISI #DRP #RFP #F3Matters #GettingBetterTogether #ScruffyCity A post shared by F3 (@f3nation_official) on Mar 23, 2018 at 8:27am PDT

I quickly realize these are both workouts and social gatherings. After my first workout, I know Ill get my own F3 nickname. I just hope mine doesnt suck. F3 nicknames are uniformly silly, often either a play on your name (last name Painter, nickname Drop Cloth) or something from your background (I meet an Ohio State fan nicknamed Schembechler, after the legendary coach of Ohio States archrival).

The guys in my session ask me for my most embarrassing life moment, then listen as I tell them about puking during a high school tennis match. Thats how I get my nickname: Ralph.

If its your first time, youre what F3 vets call an FNG (friendly new guy). But they quickly make you feel like one of the guys. And when youre battling through pistol squats and pushups shoulder to shoulder with Honey Pot, you cant help but feel like you belong.

Finding Trust at F3

A few times, Im tempted to bail, and once, I almost relive high school tennis. But I keep going, partly because of someone (Im not sure who, because Im facedown grinding out pushups) mumbling more encouragement. By the time we reach three minutes of plank jacks, the 45-minute workout is nearly over, my hair is matted, and my shirt is soaked.

Every F3 workout ends with a Circle of Trust highlighting the third F of faith. Participants count off, saying their name, age, and F3 nickname. The leader notes upcoming workouts and other community events and closes with a moment of thought-typically a prayer or a quote. Today its about love, a reference to 1 Corinthians 13: Love is patient, love is kind. It does not envy, it does not boast, it is not proud.

And Im no longer an FNG. Two days later (yes, I come back), Im officially Ralph.

Six Minutes of Mary

F3s infamous no-mercy ab burner is not for the faint of heart. Work through the following circuit, spending 24 seconds on each interval.

0:00 Little Baby Crunch

Lie on your back in situp position and lift your chest just off the ground, squeezing your abs. Thats 1 rep.

0:24 High Slow Flutter

Lie on your back, raise your straight legs about 2 feet off the ground, and flutter them back and forth. Take 2 seconds to complete each back-and-forth flutter.

0:48 Rest

1:12 Low Flutter

Lie on your back and raise your straight legs about 6 inches off the ground. Flutter them back and forth, never letting them touch the ground.

1:36 Low Scissors

Lie on your back, raise your straight legs about 6 inches off the ground, then alternately scissor one over the other.

2:00 Rest

2:24 High Scissors

Lie on your back, raise your straight legs 2 feet off the ground, and alternately scissor one over the other.

2:48 Canoe

F3s version of a modified V-up. Start lying on your back, arms and legs extended, all just inches off the ground. Tuck your knees and your arms, then return to the start. Thats 1 rep.

3:12 Rest

3:36 Heels to Heaven

F3s version of a straight-legged reverse crunch. Lie on your back, straight legs pointed upward (er, toward heaven). Tighten your abs, pressing your legs up higher and raising your lower back off the ground. Return to the start. Thats 1 rep.

4:00 Plank Jack

Start in a forearm plank, feet touching. Then leap your feet wide, then back to starting position. Thats 1 rep.

4:24 Plank

Hold a forearm plank for 24 seconds.

4:48 Rest

5:12 World War II Situp

F3s version of a straight-legged situp.

5:36 Oblique Crunch

6:00 End