Pressure differential on a swimmer’s hands and swimming direction

It is vital to maintaining a constant direction during locomotion. Turning in walking is triggered by the impulse from the leg located outside its rotation axis. Then, the centre of gravity is relocated in the direction of an inside limb [1]. It is commonly believed that similar correlation can be observed in swimming. Greater propulsion forces produced by the right limbs cause turning left. The upper and lower limps may generate the propulsion while swimming. However, its main source are the upper limbs [2]. Their activity seemed to determine the swimming direction. Hand surface is the main propulsion surface of the upper limb. Propulsion is determined by the pressure differential P(t) exerted by the water on the back of the hand and palm [3]. The purpose of this research is to check the correlation of asymmetry of pressure differentials exerted on the right and left hand with the swimming direction in breaststroke. During the research the propulsion will be produced only by the upper limbs. The analysis will be related to the propulsion phase.