Seems unlikely - collections only want to work with bills large enough that their odds of payment make it worth talking to you. Collectors never gives full price, they pay the person you owe some smaller amount, and when you pay they collect the difference.
There are levels of collections though the first is for things where they expect you will pay, you just need a payment plan (some medical labs don't do billing in house, they always sell it to collections), so collections will buy the bill for the pull price minus $50 (or some minimal amount in that range): since most people are going to pay collections just needs to setup the details for which $50 is a fair price. At the other end there are bills that they know you are not going to pay, collections will buy the a multi-thousand dollar bill for $1, and see if they can get any form of payment at all out of you.
Anyway, the bottom line is for a gym you are never going to owe enough that it is worthwhile for collections to touch it.
There are levels of collections though the first is for things where they expect you will pay, you just need a payment plan (some medical labs don't do billing in house, they always sell it to collections), so collections will buy the bill for the pull price minus $50 (or some minimal amount in that range): since most people are going to pay collections just needs to setup the details for which $50 is a fair price. At the other end there are bills that they know you are not going to pay, collections will buy the a multi-thousand dollar bill for $1, and see if they can get any form of payment at all out of you.
Anyway, the bottom line is for a gym you are never going to owe enough that it is worthwhile for collections to touch it.