Today, pole performances by exotic dancers range from basic spins and striptease in more intimate clubs to athletic moves such as climbs and body inversions in the 'stage heavy' clubs of Las Vegas and Miami. As such, proper instruction and rigorous training are necessary to attain proficiency. Pole dance requires significant muscular endurance, coordination, strength, flexibility, upper body and core stability, as well as sensuality. Amateur and professional pole dancing competitions are held in countries around the world. Pole dancing enthusiasts are of all ages although many who perform this dance and acrobatic form are adults, that does not stop younger children from learning and performing in competitions. This performance art form takes place not only in gentleman's clubs as erotic dance, but also as a mainstream form of fitness, practiced in gyms and dedicated dance studios. Pole dance combines dance and acrobatics centered on a vertical pole.