True to its name, Anytime Fitness invites its members to work out anytime—literally. The gym is open 24 hours a day, 7 days a week, so you can always squeeze in a sweat session, even if you're working a late night. And since there are more than 3,000 gyms scattered across the world, from the U.S. to Australia, you'll never have to skip your workout.

When you join, you receive a complimentary fitness consultation to help determine where you're at in terms of your goals. That should help you know where to begin when you hit the gym. Although Anytime Fitness doesn't offer classes, it has all the basics you need to boost your fitness. There's security around the clock, so you can even come in the dead of night for a run on the treadmill or a round on the elliptical. Stair climbers, spin bikes, and rowing machines also reside here, as well as free weights, dumbbells, and other strength-training equipment. Most cardio machines have TVs attached to them so you can distract your brain from your workout.

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