The top 5 gym chains, based on their size, popularity, and market presence, are:
1. **Planet Fitness**: Known for its affordability and judgment-free environment, Planet Fitness has over 2,000 locations across the United States and other countries.
2. **24 Hour Fitness**: Offering around-the-clock access, this chain has hundreds of clubs across the United States, catering to a wide range of fitness needs.
3. **LA Fitness**: With hundreds of locations primarily in the United States and Canada, LA Fitness offers a variety of amenities, including pools, basketball courts, and group fitness classes.
4. **Gold’s Gym**: One of the most recognizable names in fitness, Gold’s Gym has locations worldwide and is known for its strong emphasis on bodybuilding and weight training.
5. **Anytime Fitness**: Known for its 24/7 access and convenience, Anytime Fitness has thousands of locations globally, making it one of the most accessible gym chains in the world.