and movement. Applications to drama programmes and conservatories usually involve extensive auditions. Anybody over the age of 18 can usually apply. Training may also start at a very young age. Acting classes and professional schools targeted at under-18s are widespread. These classes introduce young actors to different aspects of acting and theatre, including scene study. Increased training and exposure to public speaking allows humans to maintain calmer and more relaxed physiologically. By measuring a public speaker's heart rate maybe one of the easiest ways to judge shifts in stress as the heart rate increases with anxiety . As actors increase performances, heart rate and other evidence of stress can decrease. This is very important in training for actors, as adaptive strategies gained from increased exposure to public speaking can regulate implicit and explicit anxiety. By attending an institution with a specialization in acting, increased opportunity to act will lead to more relaxed physiology and decrease in stress and its effects on the body. These effects can vary from hormonal to cognitive health that can impact quality of life and performance Improvisation Some classical forms of acting involve a substantial element of improvised performance. Most notable is its use by the troupes of the commedia dell'arte, a form of masked comedy that originated in Italy. Improvisation as an approach to acting formed an important part of the Russian theatre practitioner Konstantin Stanislavski's 'system' of actor training, which he developed from the 1910s onwards. Late in 1910, the playwright Maxim Gorky invited Stanislavski to join him in Capri, where they discussed training and Stanislavski's emerging "grammar" of acting. Inspired by a popular theatre performance in Naples that utilised the techniques of the commedia dell'arte, Gorky suggested that they form a company, modelled on the medieval strolling players, in which a playwright and group of young actors would devise new plays together by means of improvisation. Stanislavski would develop this use of improvisation in his work with his First Studio of the Moscow Art Theatre. Stanislavski's use was extended further in the approaches to acting developed by his students, Michael Chekhov and Maria Knebel. In the United Kingdom, the use of improvisation was pioneered by Joan Littlewood from the 1930s onwards and, later, by Keith Johnstone and Clive Barker. In the United States, it was promoted by Viola Spolin, after working with Neva Boyd at a Hull House in Chicago, Illinois (Spolin was