Keenan Adcock, 51, hikes the Timpanogos Cave National Monument trail for the 100th time this season on Wednesday, Aug. 31, 2016, in American Fork. Adcock underwent open-heart surgery to replace an aortic valve. The 1 ½ mile trail ascends 1,000 feet to the cave entrance.
Jeffrey D. Allred, Deseret News
Keenan Adcock, 51, is hugged by ranger Nancy Thoreson prior to hiking the Timpanogos Cave National Monument trail for the 100th time this season on Wednesday, Aug. 31, 2016, in American Fork. Adcock underwent open-heart surgery to replace an aortic valve. The 1 ½ mile trail ascends 1,000 feet to the cave entrance.
Jeffrey D. Allred, Deseret News
Keenan Adcock, 51, hikes the Timpanogos Cave National Monument trail for the 100th time this season on Wednesday, Aug. 31, 2016, in American Fork. Adcock underwent open-heart surgery to replace an aortic valve. The 1 ½ mile trail ascends 1,000 feet to the cave entrance.
Jeffrey D. Allred, Deseret News
Keenan Adcock, 51, touches the shiny rock after hiking the Timpanogos Cave National Monument trail for the 100th time this season on Wednesday, Aug. 31, 2016, in American Fork. Adcock underwent open-heart surgery to replace an aortic valve. The 1 ½ mile trail ascends 1,000 feet to the cave entrance.
Jeffrey D. Allred, Deseret News
Keenan Adcock, 51, hikes the Timpanogos Cave National Monument trail for the 100th time this season on Wednesday, Aug. 31, 2016, in American Fork. Adcock underwent open-heart surgery to replace an aortic valve. The 1 ½ mile trail ascends 1,000 feet to the cave entrance.
Jeffrey D. Allred, Deseret News
Keenan Adcock, 51, hikes the Timpanogos Cave National Monument trail for the 100th time this season on Wednesday, Aug. 31, 2016, in American Fork. Adcock underwent open-heart surgery to replace an aortic valve. The 1 ½ mile trail ascends 1,000 feet to the cave entrance.
Jeffrey D. Allred, Deseret News
Keenan Adcock, 51, hikes the Timpanogos Cave National Monument trail for the 100th time this season on Wednesday, Aug. 31, 2016, in American Fork. Adcock underwent open-heart surgery to replace an aortic valve. The 1 ½ mile trail ascends 1,000 feet to the cave entrance.
Jeffrey D. Allred, Deseret News
Keenan Adcock, 51, hikes the Timpanogos Cave National Monument trail for the 100th time this season on Wednesday, Aug. 31, 2016, in American Fork. Adcock underwent open-heart surgery to replace an aortic valve. The 1 ½ mile trail ascends 1,000 feet to the cave entrance.
Jeffrey D. Allred, Deseret News
Keenan Adcock, 51, hikes the Timpanogos Cave National Monument trail for the 100th time this season with ranger Cami McKinney on Wednesday, Aug. 31, 2016, in American Fork. Adcock underwent open-heart surgery to replace an aortic valve. The 1 ½ mile trail ascends 1,000 feet to the cave entrance.
Jeffrey D. Allred, Deseret News
Keenan Adcock, 51, hikes the Timpanogos Cave National Monument trail for the 100th time this season with ranger Cami McKinney on Wednesday, Aug. 31, 2016, in American Fork. Adcock underwent open-heart surgery to replace an aortic valve. The 1 ½ mile trail ascends 1,000 feet to the cave entrance.
Jeffrey D. Allred, Deseret News
The view from the Timpanogos Cave National Monument trail in American Fork on Wednesday, Aug. 31, 2016.
Jeffrey D. Allred, Deseret News
Keenan Adcock, 51, hikes the Timpanogos Cave National Monument trail for the 100th time this season with ranger Cami McKinney on Wednesday, Aug. 31, 2016, in American Fork. Adcock underwent open-heart surgery to replace an aortic valve. The 1 ½ mile trail ascends 1,000 feet to the cave entrance.
Jeffrey D. Allred, Deseret News

AMERICAN FORK — Hundreds of hikers return to the Timpanogos Cave National Monument trail day after day and week after week to get exercise.

It's "nature's alternative to the gym," said Cami McKinney, chief of interpretation with the United States National Park Service and stationed at Timpanogos Cave. She said more than 1,000 hikers return to the trail regularly because of its convenient location and to enjoy the unique experience and cardiovascular challenge that climbing 1,100 feet in just over a mile provides.

But none of them have a history quite like that of Keenan Adcock, 51, who endured open-heart surgery in April.

Adcock, of American Fork, has always been active, loves biking and lifting weights, and all that came to a stop when he was diagnosed with aortic regurgitation — his heart valve wasn't closing off or was too narrow, forcing his heart to work harder than necessary.

It was a disaster waiting to happen.

"It's a pretty bad disease — one that is typically found in patients much older than Keenan," said Dr. Gilbert Schorlemmer, a cardiothoracic surgeon at MountainStar's Timpanogos Regional Hospital in Orem. "Walking to the bathroom is a marathon for some of these patients."

And some, he said, end up with a heart attack and problems if they survive.

Schorlemmer performed an aortic valve replacement, using a valve fashioned from tissue from a cow, and Adcock almost immediately felt better. Because of the biological-based solution, he doesn't have to take blood thinners, and doctors say he's in excellent condition.

"He was always interested in trying to do what's best for his health and was willing to pursue all those things," Schorlemmer said. "It's exciting to see the fruits of your labor so well expressed as it is in Keenan."

Adcock began hiking with his daughter for rehab because it was low-impact, but when he heard about the #100hikes challenge for the 100-year celebration of the National Park Service, he was hooked.

"I like a challenge," he said, adding that he also likes "free things" and he was promised a National Park Service commemorative jacket if he completed 100 hikes on the Timpanogos trail.

"He got faster and stronger with every hike and soon, he was leaving the rangers in the dust," McKinney said. She called Adcock a "poster child for healthy lifestyles."

His first ascent along the 1.5-mile paved trail took him about 80 minutes, and he said he was "huffing and puffing around every turn." On Wednesday, he was up and down in about 30 minutes and hiked it twice that day.

"It's a strenuous hike," McKinney said. "People underestimate how difficult it is."

The rangers have gotten to know Adcock and have become friends, as they do with many of the people who make the trail a habit. Some tour the cave at the top, but Adcock sort of ceremoniously touches a "shiny rock" near the door to the cave and heads back down.

He's had to work physical activity into his schedule, taking days off from his job as a systems administrator at Salt Lake Community College to complete the challenge, but also squeezing in up to five hikes in one day on some weekends. It's something he said he couldn't have done without support from home and on the mountain, as family, friends and neighbors have joined him on the hike at times.

"Hikercizing," has Adcock calls it, "is forcing me to breathe better," he said.

He experienced a bit of a setback with some fluid buildup in his lungs resulting from his heart surgery, but he stayed motivated and pushed through, becoming one of just a dozen who completed 100 hikes on the trail from mid-May through its early closing date of Sept. 5, though more than 50 have participated in the endeavor.

"I knew I could do it, I just had to get my heart to go along with it," Adcock said, adding that he's happy it's over, that he's "looking forward to being able to do other things."

Schorlemmer said Adcock is "one of the superstars" of surgery, who should prove to others suffering with potentially scary heart problems, that it is a good thing to seek out the right help to be healthy.

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