But there are some things you should know before you join.
It turns out one muscle-bound Marine learned a hard lesson and then needed some back up from 7 On Your Side.
"It was just ridiculous," said Cathy Vesey, the Marine's mom.
For the past few months, Cathy Vesey has been fighting for her son, a U.S. Marine waging a battle against, of all places, his local gym.
Her son was blind-sided by a charge of $233; months after his membership had been canceled.
"Yes, I was really disappointed," Vesey said.
A year ago, Cathy's son Jairo joined the Marines.
Before leaving for training, he canceled his gym membership at his local Club Metro USA.
But when the New Jersey Marine returned last fall and asked the New Jersey based gym to start his membership back up, his credit card was debited more than 200 bucks.
"They had reactivated his old account and back billed him as if he was a member the whole time," Vesey said.
"When I called up they said they will refund me the money within three business days and never came," said Jairo Cortez, a Marine.
That was in October and two months later there was still no refund.
"Round and round for six weeks. Called their finance company, called their customer service, called the owner. I called everybody and no one got back to me," Vesey said.
"Before you sign up with any gym, do your due diligence," said Eric Kanefsky, the Director of New Jersey Consumer Affairs.
Experts say to study the contract before signing and remember that both New Jersey and New York allow you to cancel a fitness contract within three days after signing it.
Also, if you have a dispute, do not fear, New York and New Jersey both require gyms to post surety bonds.
"They have to post a $50,000 bond. And what that does is help us seek recourse should a company go out of business," Kanefsky said.
But this time, 7 On Your Side called Club Metro USA and got it taken care of.
"I started getting phone calls on a daily basis and they wanted to rectify the problem," Vesey said.
A company representative apologized saying its billing company made a clerical error. Just one day later the error was corrected.
"I checked my account and I saw the money was back there, so I was very pleased," Cortez said.
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