Since 2008, John Young has crossed the finish line of more than 30 triathlons, including four half-iron-distance races.

John Young is always the shortest person at every race he does. Standing at four feet, four inches, the triathlete is used to puzzled looks from his competitors. The bewilderment of race participants usually continues as Young racks his bike, a customized child’s mountain bike modified with 20-inch wheels, on the racks next to full-sized triathlon bikes.

“Like virtually everything I use in life, not much is made for me,” Young says, “but I have learned how to adjust.”

Young has achondroplasia, a genetic disorder resulting in an average-sized torso with shorter arms and legs. It is the most common type of dwarfism, affecting approximately 80 percent of “little people” worldwide.

Most people with achondroplasia find exercise challenging: Lower back problems, weaker muscles, and complications with spinal pressure often make running uncomfortable. Young, however, has found ways to thrive in endurance sports. Since 2008, Young has crossed the finish line of more than 30 triathlons, including four half-iron-distance races. Additionally, he ran a 5:57:42 marathon in November 2014, qualifying in the mobility-impaired division for the 2015 Boston Marathon (he finished in 6:39:52). His goal is to one day take on an Ironman.

RELATED: Breezy Bochenek At CAF’s Heart & Hope Gala

“With shorter arms and legs, it takes more strokes to swim or steps to run the same distance as an average-sized triathlete,” says Young. “I have done the calculations and determined with my 20-inch wheels, I need to pedal at least 35 percent more revolutions in order to go the same distance as someone using a 27-inch wheel.”

Though some may find that extra work daunting, Young sees it as fuel for his fire. His goal is not to inspire others, but to rid the world of excuses.

“It actually bothers me when people see me race and say, ‘If he can do it, I can do it.’ That really ignores all the hard work and training I’ve done to get there,” he says. “You have to want to do it. When people tell me, ‘I could never do that,’ my response has always been, ‘That’s because you don’t want to do it.’ Your will has to be stronger than your won’t.”

In addition to his modified child’s mountain bike, Young has found ways to adapt equipment to meet his training and racing needs. Some of his modifications:

“I use a two-piece wetsuit. I have a sleeveless Orca top along with neoprene shorts that were originally intended for kayakers.”

“I run in women’s shoes (size 6.5) and have found both K-Swiss and New Balance shoes that work great.”

“I have to be careful to use the shortest tri shorts possible, as many current brands actually go well past my knees.”

RELATED – I’m A Triathlete: Sanjay Gupta