But before you spend your hard-earned money on a membership, how can you figure out which one is right for you? How can you make sure it will provide what you need, and that you'll enjoy it enough to keep going back?
Finding an exercise facility that fits your needs doesn't have to be time-consuming or intimidating, experts say. All it really takes is knowing what you're looking for and asking the right questions.
What questions should you be asking? Three fitness experts gave WebMD 10 things to consider before joining a fitness facility.
1. What Do You Want from Your Workout?
This is the starting point. Decide what you want from exercise, and what type of exercise you want to do. Do you love to swim? Or is yoga your true calling? Will you be happy running or walking on a treadmill? Or do you need the latest cardiovascular machines to help keep you motivated? Do you want to improve cardiovascular endurance, build strength, enhance flexibility -- or just make it through a workout without getting bored?
If you choose an activity you like, says certified personal trainer and fitness nutritionist Lynn VanDyke, you're more likely to stay with it.
If variety is your thing, you need a gym with plenty of machines and lots of classes. If you just need to get in and out and sweat for 40 minutes, don't pay for all the extra classes and amenities you won't be using, advises VanDyke, who trains in Chester County, Pa.
If Pilates or yoga is what moves you, you might want to join a studio rather than taking classes at a health club, says Pilates instructor Tracey Mallett.
''A studio is generally a better setting to do that kind of exercise,'' says Mallett, who owns ATP Specific Training, a Pilates and physical therapy studio in South Pasadena and also teaches at a local YMCA.
That's because a studio is quieter and smaller, and instructors tend to be specialists who can offer more personal attention to clients, she says.
2. How Convenient Is the Facility?
Location is a major consideration, says Cedric X. Bryant, PhD, chief exercise officer for the American Council on Exercise (ACE).
''Think about the proximity of the facility to where you live or work,'' he says. ''The No. 1 reason people don't stick with (exercise) is lack of time. If it's not close to either where you live or work, it's more of a challenge to get there regularly.''
Decide when you're going to work out most of the time, he says. If it's in the morning or on weekends, a facility close to home may be best. If you want to fit your workout in during lunch or after work, choose a gym close to work.
''Any place more than 3 to 5 miles away from home or work, and you're more likely to make excuses not to go,'' says VanDyke, who used to manage a fitness facility.
Mallett, a mom of two preschoolers, enjoys a rare luxury living in Los Angeles. Her studio is four-tenths of a mile from her home. The YMCA where she teaches is around the corner.
''Less than four miles away is probably the best gym in town, but I choose to go to the little Y on the corner by my building,'' she says. ''If it's not close by, I'm not going to go. I don't have the time with two small kids.''
If someone in the fitness industry doesn't want to go 4 miles to work out, imagine how onerous this could get for the recreational exerciser!
3. What Kind of Credentials Does the Staff Have?
People often forget how important it is to have qualified staff there to guide them on proper alignment on a machine, or proper form in a class, say our experts.
''Interview members of the staff and a few of the trainers,'' says VanDyke. ''Ask [trainers] how they're certified, and do research on it yourself if you're not familiar with the credentials they tout.''
Though many clubs pride themselves on the quality and education of their staff, there are others who are less conscientious about certification, Bryant says.
You cannot afford to be that way, the experts say. You don't want to get injured doing something you shouldn't be doing, or are doing incorrectly.
4. What Are the Facility's Emergency Procedures?
Not only should the staff know how to coach you through the equipment, they should know how to handle a medical crisis, should one arise.
It may not seem important to you starting out, but it's crucial that any fitness facility have safety and emergency procedures in place, says Bryant.
One thing you should ask is whether the facility has an automated external defibrillator (AED), a machine that analyzes a person's heart rhythm, determines if an electrical shock is needed, and delivers the shock. An AED's use while waiting for paramedics to arrive can be life-saving.
''If the club doesn't have an AED,'' says Bryant, ''I would think about finding another facility.''
5. What is the Equipment Like and How Is It Maintained?
When touring local facilities, take a look at the equipment. Don't just find out if they have elliptical machines; find out how many they have, how busy the machines seem to be, and how often they're serviced.
A variety of equipment is great, says VanDyke; you want a full-service gym to have a little of everything. But there's more to consider.
''Test it out,'' she says. ''Is the equipment clean? Are there sprays or wipes that you can see throughout the gym for cleaning the equipment? Are there signs that say 'OUT OF ORDER'?''
You can discover all this during your initial tour of the facility simply by being observant, adds Bryant. Are the locker rooms unkempt? Are the showers dirty or leaking? Is the hot tub cloudy? Do the machines look like they're in poor condition? If so, it's not the place you want to spend your money or your time.
6. What Amenities Are Offered?
In addition to access to machines and free weights, most memberships at full-service clubs include group fitness classes, lockers and showers, towels and -- depending on the size of the club -- racquetball and tennis courts, and a pool.
If the club you choose offers many of these options, expect to pay more than you would to join a small fitness center with a few treadmills and free weights.
7. What Are the Hours?
Consider your own schedule here. Don't necessarily be lured by a gym that's open 24 hours, or turned off by one that keeps banker's hours. The important thing is that it is open when you plan to work out.
''If the facility has limited hours and you need more flexibility, then it's not the best choice for you,'' warns Bryant.
On the other hand, if you have a flexible schedule, you may be able to save money and time with a mid-day membership. This is the least busy time at a gym; so it may offer lower prices for those willing to come during these off-peak hours.
Visit the gym during the hours you will be working out. This will give you a feel for how busy the club will be and what's offered.
''Sometimes if you visit during non-peak times, that's not how it's going to be. If you're going to be fighting for machines, you may not like that,'' Bryant says.
''Lots of times, people will say, 'We have 50 classes a week','' says VanDyke, ''but you're not going to be there 24 hours a day. If you can only go between 5 and 6 a.m., there probably aren't a lot of classes being taught at that time.''
If you want classes, find out when the ones you want are offered. If you want to swim, find out when the open swim times are and be sure they fit your schedule, she says.
''Before you sign a contract or put down that registration fee,'' says VanDyke, ''take a step back and figure out what is available during the hours you can get to the gym.''
8. What Is the Total Cost?
Fitness is not cheap. Whether you join a studio or a full-service gym with day care, showers and a pool, you'll be incurring a new expense.
''Unfortunately, people do not look at it as an investment in their body," says VanDyke. "They look at it as another bill.''
Cost is usually tied to what the gym has to offer, says VanDyke. Don't pay for the newest, nicest health club if you're never going to need the showers, the lockers, child care, or the pool. If all you want is to run on a treadmill, there may be a less expensive option in your area. Instead of $150 a month, you might pay $30.
If a spouse and children are in the picture, ask about family memberships, adds Mallett: ''You're probably going to save money by doing that.''
Whatever gym you join, read the fine print, says Bryant.
''Inquire about payment policies,'' he says. ''If they ask you for a long-term commitment, that would make me a little leery. Most places don't lock you into something long-term.''
Find out if there are allowances for special circumstances, such as the birth of a child or the illness of a parent, suggests Bryant. Ask about the club's policies on temporarily freezing a membership or adjusting it to fit your needs.
''We live in such a time-pressured, hectic society,'' he says. ''We have seasons of life, and there may be a season where it's just too hectic for you to get to the gym.''
9. Is There a Reciprocity Agreement?
If you travel a lot, make sure the club you join has a reciprocity agreement with other clubs, suggests Bryant. For example, membership to an International Health, Racquet and Sportsclub Association (IHRSA) club allows you access to IHRSA clubs in other cities.
The more consistently you exercise, the more likely it is to become a part of your daily life. Having a club close by when you're out of town will keep you honest and committed to your fitness regimen.
10. What Kind of Reputation Does It Have?
It's a good idea to talk to other members about the quality of the club you're thinking of joining, and to find out what they like about it.
But don't be afraid to get some impartial information, too. Bryant suggests checking with the Better Business Bureau to see if any complaints have been lodged against the facility you're considering.
In the final analysis, says Bryant, go with your gut.
"You want to find a facility where you can be most comfortable - a place with the equipment that's going to help you stick with it," he says. "That's how you're going to derive the long-term benefits."