You don't need a gym membership to get in a good workout. Bodyweight exercises, which you can do at home or at the park, will do the trick. But economist Allison Schrager argues in that if you're going to belong to a gym, you should splurge on an expensive one (if you can afford it).

The , especially low-priced ones, counts on many members rarely (or never) showing up. It's human nature to not care about losing $10 per month on a cheap membership. But if you're shelling out $100 per month, you're going to start feeling guilty if you're not going to the gym.

It's not just the fear of wasting money that makes people show up. A 2006 found people whose companies paid for their memberships to expensive gyms went about as often as those who footed the bill themselves. Luxury and the allure of a high-end product seem to play a role in getting us to find time to work out, regardless of who's paying.

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