"It was more fun than I thought it was going to be," said Lewin. "It was definitely a unique experience I was hoping to get — seeing the skyline, Intrepid, different landmarks going around Hudson Circle, around Battery Pier, all (of the) different ferries, going by the Statue of Liberty. It was cool seeing the orange Staten Island Ferry."
Lewin, who swam competitively at Swampscott High School and Boston College, completed the first leg last year when he completed the grueling 21-mile Catalina Channel swim, which stretches from Santa Catalina Island, a rocky island off the California Coast, to Los Angeles.
He'll take some time off and then shift his focus to taking on the third leg, the famous English Channel swim, which is 21 miles from Dover, England, to Cap Gris-Nez in France. But he expects he wouldn't attempt that swim until 2021, due to its high expense and need for intensive training.
Lewin said the Manhattan swim presented a different challenge than the Catalina Channel. He joined 15 other swimmers for a morning swim on Saturday, a vastly different experience than Catalina, a solo swim overnight.
Where he fought exhaustion and struggled to stay awake last year, he had to try to stay focused on his own swim this time, and block out what the other competitors were doing.
"It's not a race, (but) whenever you're swimming with people, you're always trying to catch up, (and) use them as motivation to keep the pace up," Lewin said. "For me, the challenge was trying to hold myself back and not getting into anyone else's swim."
Another major challenge was a warmer water temperature than he expected. Lewin was expecting water to be in the mid-60s, but at one point, he said the temperature reached 77 degrees, which led to overheating, sweating and dehydration.
Taking his feeding from his kayaker every 30 minutes wasn't doing the job — when he started cramping, he switched to feeding every 20 minutes until the pain stopped.
What a lot of his training focused on was keeping his speed up. Unlike in Catalina where he could keep going and eventually get pulled in with the tide, he had to make sure he made each current because the heavily trafficked boating channel in Manhattan can become dangerous. If swimmers miss the currents, they're unlikely to finish and likely to get pulled out of the water by officials.
To prepare, Lewin said he trained at Phillips Beach in Swampscott for months. He trained four to six days a week in four-week blocks, which started with a speed week followed by increased volume, or distance weeks. He would swim one to seven hours a day. A peak week would consist of swimming 35 miles, while a typical one would be 20 to 25 miles.
What made Saturday's swim fun, Lewin said, was having visible support on both the boat alongside him and on land. His support crew included his father and his wife on the boat and the father of one of his friends, who was his kayaker.
Outside the water, his sister, brother-in-law and mother ran around Manhattan, going from pier to pier to keep up with his progress. His kayaker would point them out throughout the event.
"Every time I would breathe, I would look for them," Lewin said. "To see them there was very special."
Lewin, who founded Endurance Swimming about a decade ago, credits the support of the community for showing an interest in him and keeping him motivated. Otherwise, swimming would be a lonely, difficult sport, he said.