But woe betide those who don't read the small print. Gyms across the country insist that new customers sign long-term deals that tie them to regular payments for up to 24 months.
Try to quit and consumers find themselves forced to either continue paying or fork out for penalty charges that are often equivalent to the remainder of the contract, even if they suffer an injury or become unemployed.
Now the Office of Fair Trading is to crack down on fitness centre contracts that impose hefty charges on customers who try to quit.
The OFT has already taken one company, with 700 outlets, to court over unfair terms, and it is expected to announce forced changes to such contracts.
And according to the Daily Mail, the OFT is taking a close look at the small-print from major firms like LA Fitness, Fitness First and Bannatyne's.
"These include tying consumers into lengthy terms with limited rights to cancel should their circumstances change, and using misleading debt collection practices."
Virgin Active has reportedly already extended the notice period in which members who have been made redundant may cancel their membership, as well as offering cancellation rights to those who lose their job in other circumstances.
Others have recently cut their minimum contract terms, with Bannatyne's offering 12-month contracts and Fitness First providing one-month and four-month deals.
Have you been caught out by gym contract small print? Leave your comments below...