Ryan Hall is one of the country’s greatest endurance athletes, holding the record for the fastest marathon (2:04:58) and half-marathon (59:43) run by an American. He retired in 2016 in his mid-30s, but at an age when most men are doubling down on cardio, Hall decided to add muscle.

“So many pro athletes lose purpose when they retire,” Hall says. “I loved the challenge of running, but I took it as far as I could take it. My body wasn’t having it anymore. I wanted to keep challenging myself, so I wondered how much muscle I could put on? How strong could I get? It’s been a mad science experiment.”

Over the last several years, Hall has dedicated himself to bulking up, going from a 130-pound lean, marathon-running machine to 190 pounds of dense muscle. The transformation is remarkable, not only because Hall added more than 50 pounds of muscle, but because he’s successfully shifted his fitness and physique at an age when most of us are just trying to hang on to any gains we made in our youth. Hall is about to turn 40, and he’s transformed himself into a functional fitness powerhouse who’s knocking out crazy feats of strength most of us wouldn’t dare dream.

Man wearing black T-shirt chopping wood in gloves — Courtesy Ten Thousand

In October, he split a cord of wood before running to the bottom of the Grand Canyon, where he filled two giant jugs with water (62 pounds) and farmer’s carried them back up to the rim—gaining 5,000 feet of elevation in the process. Hall says splitting the wood took longer than he thought (a cord of wood fills up two 8-foot-bed pickup trucks), but it was the farmer’s carry back up the Grand Canyon that proved the most difficult.

“I remember looking up toward the rim from the bottom and wondering what I got myself into,” Hall says. “The farthest I could go without setting them down was about 45 seconds. It was like doing intervals, carrying them as far as I could, breathing super hard and tasting copper in my mouth. It was like that for five hours straight.”

Man carrying jugs of water up Grand Canyon — Courtesy Ten Thousand

Carrying 124 pounds of water up the Grand Canyon is a dramatic feat of strength, but most days, Hall is putting in the work solo in his garage and backyard. He hasn’t worked with a strength coach at all during the process. Instead, he read Arnold Schwarzenegger’s Bible of Body Building and consumed as much info as he could on powerlifting. His home gym is a work in progress (he just added a leg press machine) but consists mostly of a power rack and some barbells. Hall never misses a day in the gym, but only dedicates an hour to working out each day, rotating through different muscle groups, because he doesn’t want his fitness obsession to interfere with his family time and thriving coaching business.

“When I started, I had a goal of benching, squatting, and deadlifting 300 pounds,” Hall says. “At that time, moving 300 pounds of weight seemed insane to me. But now I’m benching 330, squatting 480, and deadlifting 530.”

Those are impressive weightlifting hallmarks, but what’s more important to Hall is that he’s feeling better now than he did at the end of his running career.

“I was in a bad spot when I retired,” Hall says. “I was weak, small, and had low testosterone levels. I was tired all the time. You have to train as hard as your body can handle as a pro marathoner, but your body can only sustain that kind of effort for so long. I was a zombie all day long. Lifting has been a way for me to give back to my body—get my energy and life back. It’s been good for me mentally and physically.”

There’s plenty of scientific studies to support Hall’s claims, too. According to the Mayo Clinic, muscle deteriorates with age and is replaced with fat at a staggering rate. Most of us lose 10 percent of our muscle mass per decade starting in our 30s. Strength training as you age can help preserve muscle mass, strengthen bones, and manage chronic conditions associated with aging, like arthritis, back pain, and heart disease. Studies also show that weight training can help elevate your mood and boost testosterone levels in men, particularly as they age.

Man carrying blue jugs of water up Grand Canyon — Courtesy Ten Thousand

“We have to redefine what we think of as old,” Hall says. “I’ve been talking myself through that recently. I’m turning 40. How can I frame this in a more positive way? We’re aging, yeah, but we’re also evolving. We’re not supposed to stay the same. We need to change our view of what’s possible.”

Hall is still experimenting to figure out what’s possible with his own body, developing a series of feats of strength that are as mind-numbing as his wood chop and water carry in the Grand Canyon. He has a goal of deadlifting 500 pounds, then running a sub-5-minute mile. And for his 40th birthday, he’s hoping to complete a 500-pound yolk carry—where the weight is distributed on a bar in four different locations—for 5K. Hall figures it’ll take him five hours and be more intense than his Grand Canyon farmer’s carry.

“I’m training with 525 pounds on the yolk right now. It’s so intense,” Hall says. “I carry it for 10 or 20 meters and I feel like my eyeballs are gonna explode. I love stuff like that. I like to feel the pain of the marathon. The pain of carrying water jugs up the Grand Canyon. That’s what makes me feel alive.”

Carrying jugs of water up stone stairs — Courtesy Ten Thousand

Ryan Hall Shares 5 Rules for Getting Stronger

1. Nutrition is everything

Nutrition is the biggest component to strength training. Putting enough food down is also the hardest part of gaining muscle. I eat every three hours on the dot. Lots of calories and lots of protein. It’s crazy. I can do the same exact training, but if I’m not eating enough, I’ll lose strength. If I kick my calories up, I see progress and start feeling better.

2. Don’t be scared to get soft

The bulking phase is an important part of gaining muscle. You have to eat a lot of food and put on weight. Most guys are afraid of getting soft. They freak out if they can’t see their abs. You have to let go of that. During my bulking phases, I look so round and bloated, but that’s just part of the process.

3. Set the bar low

Don’t aim for a 500-pound deadlift in two weeks. And don’t make yourself lift for hours at a time. Consistency, not punishing yourself, is the key to gains. It’s crazy what you can accomplish in short amounts of time. I trained for the Grand Canyon farmer’s carry in just 20 minutes a day. That’s it. Set the training bar low so you can stick to it.

4. Make it fun

Choose two or three exercises you like to do, and do them for 20 minutes a day. For me, it’s heavy carries and jumping rope. I can kill myself for 20 minutes, alternating between those two exercises, and have fun with it.

5. Build cardio into your weight training

You probably don’t have time to run or bike and lift in the gym. So cut the rest time between sets to just 45 seconds. It’ll keep your heart rate up and keep your cardio in decent shape. I can run a 5-minute mile without training for it if I follow that plan.