A Greenwich COVID-19 survivor is taking part in a 37-day physical challenge, mirroring his time in the hospital a year ago, to honor the doctors and nurses who saved his life.

Gabriel Cid is more than halfway through the challenge that he's named the Cidman37. It's 37 straight days of working out with trainer Shawn Harris, who came up with the idea.

"I spent 37 days fighting for my life in the hospital, so he goes, 'We're going to spend 37 days fighting for your health,'" says Cid.

"I'll tell you what, he never quits and he always wants to do more," says Harris.

It's a stark contrast to a year ago, when Cid was in the intensive care unit at Greenwich Hospital.

"I had it rough. I was ventilated for 21 days, the ICU nurses told me they didn't think I’d make it out," he says.

But Cid survived - leaving Greenwich Hospital after 37 days.

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"When I left the hospital, people would ask me, 'What are you going to do with your second chance at life?' And that's a very deep and heavy question for someone who went through what I did," Cid says.

The answer was honoring the doctors and nurses at Greenwich Hospital by taking care of himself and leading a new, healthy life. He says before the pandemic, you would've never found him at a gym.

"I was about 297 pounds, completely out of shape," says Cid. "Walking my dog was the most active I was."

So this isn't just the best shape Cid's been in since the pandemic - it's the best shape he's been in ever.

His initial goal was to run a 5K to Greenwich Hospital on April 12 - the one-year anniversary of when he was rushed there. That ended up becoming just the start of the Cidman37.

Cid has documented the challenge on social media, hoping to inspire other COVID-19 survivors. He's also using it to raise money for Greenwich Hospital and give back to the place that gave him so much.

"You can use this disease as a springboard to something better for yourself," he says.

Cid will end his Cidman37 on May 18, when he'll donate a check to Greenwich Hospital and then run a 5K from there.