Dave Coyne was just two blocks from the finish line in the 2013 Boston Marathon when the first bomb exploded. “I looked up to the sky because I thought it was a jet breaking the sound barrier,” the veteran marathoner recalled. “When the second bomb went off, I had a bad feeling.”

Police moved in quickly, stopped the runners and sealed off the area to search for bombs. When the dust had settled, the two explosions on the sidewalk near the finish line had killed three spectators and injured 264 of the 23,342 runners.

If Coyne hadn’t been slowed down by calf cramps, he surely would have already crossed the line and not been an eyewitness to the tragedy.

Now it’s a year later, and the 2014 Boston Marathon is April 21. Coyne will be there, marking some personal milestones — his 43rd Boston Marathon, and 80th marathon to date. For the president/co-owner of New Way Equipment Home & Pool Center in Avon, N.Y., it’s important to join in the race. “I believe we’ll go back and be Boston Strong, and we’ll wear shirts that say that,” Coyne said. “There will be more runners this year. They typically release them in three waves of 9,000 runners each, but this year there will be a fourth wave.”

The 62-year-old has enjoyed running since his days on the high school cross-country team. “Probably it’s a gift I’ve been given,” he said. “Running comes easy to me.” He’s been doing marathons since 1969, when he entered the Boston event at age 17.

Coyne typically runs six to eight miles daily. On Wednesday nights, he and 11 other guys run seven to nine miles on the hilly campus of SUNY Geneseo College. On Sundays, they take a long run at different locations, covering more than 18 miles.

And those are just Coyne’s regular running days.

When training for a marathon, his workouts intensify. He alternates the running days with cross-training days, using the elliptical machine, doing 200 sit-ups and lifting weights. The closer he gets to race day, the more he works out.

Over the years, his times in the Boston Marathon have been impressive: He came in 30th in 1986, and was in the top 100 for 12 years. In 1983, he finished in 2 hours, 20 minutes; now he runs about an hour slower.

Coyne also does triathlons. “I train with bicyclists in their 20s and 30s,” he said. “I’m able to stay with them, then they pass me on the hill. I get my breath back at the top, and I take off while they’re [catching their breath].”

When he isn’t competing, Coyne is just as dedicated to his family’s business. The company is owned by founder Ted Coyne and his sons, Dave and Alan — plus their sons, Robert and Jason, also work there. The firm carries aboveground pools, spas, equipment and backyard products.

Dave Coyne has been with the company 42 years, starting in pool construction in the summer during high school. After college studies, he took an interest in retail; his brother, Alan, is “the outside guy.” What Dave likes most about the business is the people, and he knows more than half the customers by name.

“A lot of people ask me how the running is going,” he said, adding that there has been local press coverage. “I’m kind of known around here. Rochester is 20 miles away, and they call me ‘Mr. Boston.’”

As if all that weren’t enough, Coyne also is a scuba diver and an avid tennis player, hitting the courts twice a week. No wonder he’s a force to be reckoned with whenever, wherever he’s competing.