The secret to being able to jump through in a vinyasa is not in the ability to jump but in the ability to brake! Everyone can jump. In fact you hold yourself back from jumping if you do not have the strength to brake your jump. Your body inherently knows if you do or do not have that strength and will even override your conscious attempts to jump in order to protect you. Luckily! How brilliant is that?!
With Pincha Mayurasana starts the strength section of the Intermediate Series of Ashtanga Yoga. This first posture focuses on stabilizing of the shoulderblades (scapula).
In case of an existing shoulder injury, jumping out of the posture (vinyasa nine) may need to be modified.