Sunlight streams through a wall of windows at the George E. Wahlen Veterans Affairs Medical Center in Salt Lake City as Bryant Jacobs takes a lap around the room.

He makes a turn around a set of treadmills and takes another lap inside the hospital's new $5 million physical-therapy center.

His physical therapist, Bart Gillespie, looks on.

"Time," Gillespie finally calls. "That's 6 minutes. Stop right there."

The walking path is 172 feet long. Jacobs has gone just shy of eight laps. At that rate, it would take him about 24 minutes to walk a mile. It doesn't seem likely he could do that, though; he's sweating and panting at the quarter-mile mark.

"That's not a bad start," Gillespie says.

"It sucks," Jacobs replies. "I'm getting cramps in my stump."

"But you're walking — you're moving pretty good," Gillespie says.

The way Gillespie sees it, Jacobs has made solid progress since his amputation, now nearly six months in the past. His gait is consistently improving; if Jacobs were to wear pants, rather than his usual shorts, few people would suspect he was missing a leg.

He's driving now, using his left foot as most drivers would use their right. The phantom pains he suffered in the months after the surgery used to keep him up all night; now they're rare. He's been able to cut his intake of painkillers in half — and has plans to go lower.

But Jacobs isn't satisfied.

"Everybody says it's a fast progression, but I don't really feel that way," he says. "Day to day, I'm getting sores on my leg. My socket still doesn't fit right — and that's distracting. I'm ready for the day when I can just put it on and be done with it."

It never really works that way. Residual limbs are swollen after amputations, so prosthetists know the first plaster cast they make for a socket is just the start. When amputees get into shape, as Jacobs is trying to do, the residual limb often shrinks. And in the hours between morning, when fluids have gathered in a limb overnight, to the afternoon, when everything is circulating better, a residual limb can lose an inch in circumference.

"It's a moving target on top of a moving target," says Jacobs' prosthetist, Lane Ferrin, who has employed suction, snowboard boot-style dial-down cables, and even Velcro to try to get Jacobs' socket to hold snug. "I know how frustrating that can be for some patients. But little by little they get more comfortable with it."

After nine years of limited exercise, Jacobs is battling to drop weight and get into better cardiovascular shape.

He was certain that by now he'd be golfing. But as the oak leaves start to fall on his home course, it looks increasingly as though he might have to wait until the spring.

"During all of this my expectations have been higher than the reality of what my body was willing to do," he says.

Slowly, he's grown more comfortable with his prosthetic. He's in it more each day. And each day he's thinking less about the fact that it's even there.

A year ago, just about any kind of exercise would put him out for a day or two afterward. His body would punish him with pain. Now, he could exercise all the time if he wanted.

"It's been hard to adjust to the mentality that I can actually do all this stuff every day," he says.

In early October, he heads to central Utah for a three-day hunt arranged by nonprofit Warriors Afield Legacy Foundation at the Castle Valley Outdoors lodge. By the final day of last year's hunt, Jacobs was in a lot of pain.

Now, as a Polaris four-wheeler driven by a foundation volunteer rumbles across the scrub grass, Jacobs feels as though he could keep going for days.

When a shorthair pointer named Pete freezes up ahead, nose still and tail stiff, Jacobs slides from the passenger seat and steadies himself against the roll bar. Pete's quarry takes to the air. Jacobs trains his shotgun on the bird — a fluttering rainbow against the redrock buttes. He pulls the trigger, and then again. When the bird falls, Pete runs joyously after.

"Yeeeee-ah!" screams a craggy voice from the other side of the field. "Hooah Bryant! Great shooting!" Jacobs' hunting partner, a retired Army colonel named Dick Rock, is overjoyed. "That was beautiful!"

This is the second year that Rock, a Vietnam War veteran, has been assigned as Jacobs' mentor. When they met up last year, Jacobs had told doctors at the VA he was ready to have his leg removed. But Rock says the younger vet still seemed uncertain.

Jacobs tells Rock that he's battled doubts in the wake of the surgery too, but now he knows the amputation was the right choice.

And next year, he says, he hopes he won't need the four-wheeler.

Jacobs never felt any ambition to participate in a marathon.

But Travis Wood, his friend and fellow amputee, has suggested competing in New York with a group of disabled veterans sponsored by the nonprofit Achilles Foundation. Jacobs agreed.

Jacobs will wear bib 444 in the handcycle division of the 2014 New York City Marathon.

Rising in his room at New York's Union League Club at 3:30 a.m. on Nov. 2, the day of the race, he's feeling wary.

"I'll finish," he says. "There's no way I'm not going to finish my first marathon. But I feel like I could have done more to get ready."

He's not sure how many miles he's put in on his handcycle since it arrived about two months ago, though he's worked up to hourlong sets on the rowing machine at the VA hospital's physical-therapy center. "Nothing close to 26 miles, though," he says with a sigh.

A stream of veterans pours into the Union League banquet room. There are single amputees, double amputees, triple amputees. Some are in their 20s. Others are in their 60s. They wear Achilles Foundation race jerseys and smiles that belie the hour.

At 4:30 a.m., the group walks and rolls down to Fifth Avenue, where it loads onto a bus in a miles-long convoy of buses and waits for thousands of other racers to do the same. Some sleep, others listen to music or read paperbacks. Some racers are sharing stories about other marathons.

"You done Chicago?" someone says. "Nah man, Chicago's on my bucket list," another responds. "Oh yeah, man, you gotta do Chicago," yet another racer proclaims. Like a soldier awaiting his first mission, Jacobs quietly takes it in.

Bad news comes before the bus even gets underway: 50-mph wind gusts over the Verrazano-Narrows Bridge, connecting Staten Island and Brooklyn, have prompted race organizers to rule that wheelchair racers won't be permitted to start with the rest of the competitors. Instead, their race will begin in Brooklyn — 3 miles into the course.

A collective groan takes over the bus. Someone jokes about making a bumper sticker that reads "23.2." Jacobs' face tightens.

"It's not so bad not having to go over that bridge, because I heard that part is really hard," he says. "But this was supposed to be my first marathon."

Michele is waiting in the grandstands as her husband's teammate Freddie De Los Santos — also an above-the-knee right-leg amputee — sprints across the finish line at the 1:17:28 mark to take first place in the handcycle division. Wood rolls through 20 minutes later.

She's there as the first able-bodied runners — a virtual United Nations delegation of Kenyans, Ethiopians, Latvians, Portuguese, Ugandans and Americans — finish to an eruption of enthusiastic applause, flag-waving and photo-taking.

She's shivering. Her nose is running. She needs to use the restroom. But she won't leave here until her husband crosses.

The two-hour mark comes and goes. She'd planned to track him on her phone — but since the wheelchair racers were forced to start 3 miles in, the tracking chips in their race bibs weren't logged into the system.

The three-hour mark comes and goes. A handcyclist rounds the final corner. It looks like Jacobs, at first, but it's another racer.

He told her it would probably be a long wait. But he promised that, as long as he knew she was there, he wouldn't stop until he finished.

"Bryant comes from a big family of runners," she says. "His grandpa, his brothers — they've all done all these marathons and races. And I think this is his way of being part of that, even though he can't be a runner quite yet."

Finally he appears, heaving his body up and down, driving the wheels up the final hill. She screams and whoops and calls his name as he passes. He crosses the line at 3:08:43 — 48th in a field of 59 handcyclists.

"Oh man, that sucked," Jacobs says when he's reunited with his wife a few minutes later, a medal dangling from a rainbow ribbon around his neck. "It hurt so bad. Especially the end. The wind was so rough. And it's so cold."

"But you did it," Michele says.

"I did it," he says. "That feels pretty good to say."

It takes just under five hours to get back to Utah on the morning after the race.

There is no snow on the Wasatch Mountains as their plane approaches Salt Lake International Airport.

But it's coming. And when it does, he wants to be ready for it.

That's his next goal.