Weight loss on the way to the New York City Marathon

When Kim and Daniel Held attended a baby class before the birth of their first son, they got more than just a wake-up call that they were about to become parents. They got a wake-up call about their own health, too.

"We were sitting, and he couldn't sit behind me," said Kim Held, 28, of Albertus, Pa. "That was the breaking point."

That day was in 2011. On Sunday, Held will run the New York City Marathon, her first full marathon. It's a cap to her journey of losing 40 pounds. Daniel, who ran the same marathon last year, has lost 70.

The couple started getting healthy first by eating better and exercising. For him, that exercising was running. For her, that was walking short loops around their development until her son was born. The first day she was cleared for it by her doctor, she started running too.

"I could not wait to be able to start running," she said.

The first time she ran a mile, she finished in 12 minutes, 30 seconds. She ran her first 5k in 2011 and finished in 31 minutes. She dropped that time to 24 minutes by the next year.

The Helds have become fitness enthusiasts. They've done triathlons and half marathons and, last year, Daniel ran the New York City Marathon while she was pregnant with their second son (she ran a half marathon soon after his birth). She's also become a fitness instructor, teaching classes in aerobics, water aerobics, boot camp and spin at Steel Fitness Premiere in Allentown, Pa.

Both Helds and Kim Held's cousin entered the lottery for the 2014 New York City Marathon. Kim was leaving the gym when her husband called her to let her know she got in - and that she was the only one out of the three who made it in the lottery (runners had a 12 percent chance of getting in through the lottery for this year's race, according to the New York Road Runners).

"I couldn't believe it," she said. "It felt unreal until I started doing the longer training runs. Then it set in."

Her mother babysat for the couple every Sunday as they did their long runs together, ending with a 20-mile run two weeks before race date. Daniel isn't running a marathon this year, but trained so that she'd have company while out on those long runs.

Held doesn't have many expectations for Sunday, though she'd like to run the race in under 41/2 hours. Race organizers expect that the one-millionth finisher of the history of the New York City Marathon will finish between 4 hours and 4:10.