Nijinsky in his prime

In mid-May 1910 the dancers left for Berlin, where they had their first performance on 20 May. Nijinky had turned twenty in March, and he continued to grow as a dancer. His sister Bronislava, who was a year younger and a talented ballerina in her own right, joined them for this tour, and in her memoirs she described her brother's progress, with an eye for detail that one would find only in a fellow dancer:

While Vaslav, apart from the others, practised his dance exercises alone, I observed him from a distance. He executed all his exercises at an accelerated tempo, and for never more than forty-five to fifty minutes; that would be his total practice time. But during that time he expended the strength and energy equivalent in other dancers to three hours of assiduous exercises . . . Vaslav seemed more intent on improving the energy of the muscular drive, strength, and speed than on observing the five positions . . . He worked on the elasticity of the whole body in the execution of his own movements. Even when holding a pose, Vaslav's body never stopped dancing. In his adagio exercises, in the developpe front, he could not raise his leg higher than ninety degrees; the build of his leg, his overdeveloped thigh muscles, as solid as a rock, did not permit him to attain the angle possible for an average dancer.

In the allegro pas he did not come down completely on the balls of his feet, but barely touched the floor with the tips of his toes and not the customary preparation with both feet firmly on the floor, taking the force from a deep plie. Nijinsky's toes were unusually strong and enabled him to take this short preparation so quickly as to be imperceptible, creating the impression that he remained at all times suspended in the air.

Diaghilev: A Life by Sjeng Scheijen. 2009. Page 200.