Frills equal distractions when it comes to working out. That's according to the certified trainers who own CrossFit Liger, a member of the gym family named the sixth-best in America by The Active Times. That's why none of their classes involve fancy treadmills, designer rubber bands, or high heels. Instead, classes feature trainers such as Dr. Adam Locker leads students through group classes and personal-training sessions, and seasoned coaches who oversee each participant, monitoring progress as they deliver safety tips and words of encouragement.

Gymnastics-inspired bodyweight exercises such as handstands and muscle-ups build lean muscle mass, and plyometrics foster agility and stamina. Many sessions also incorporate running or rowing to raise heart rates and melt calories. In addition to sculpting lean muscle, kettlebell training cultivates flexibility with focused squats and swinging motions. Instructors also instill in their clients the CrossFit style with functional movements that aim to boost strength, power, and coordination.

Workouts take place in warehouses and other spartan spaces that embody a cultivated lack of the bells and whistles that often masquerade as fitness essentials. Here, basic tools such as kettlebells, jump ropes, and weighted sleds get the job done for a wide range of exercisers, from absolute beginners to advanced athletes.