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8/11/2019 Tennis Biomechanics

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1. Flexor Digitorum Superficialis

2. Flexor Digitorum Profundus

4 Heads

3. Flexor Carpi Radialis

4. Flexor Carpi Ulnaris

5. Palmaris Longus

6. Flexor Pollicis Longus

:2&,6


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Moment of inertia of ball is fixed, contact time is affected by

racquet stiffness and string tension, but it is torque you can

control the most via the path the racquet moves during contact.


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6

Slight

Topspin

Heavy

Topspin

The modern tennis forehand is a brushing action

behind the ball. The full swing path is like a

windshield wiper brush. But the ball is on the

strings for approximately 4 milliseconds so the ball

does not leave with much sidespin.

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Air has to travel further over the top of the airfoil,

hence greater velocity and less pressure.


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10/1410

Top-spinNo-spin

Friction (in negative direction) is less in the topspin

case (can even be positive). Hence, the horizontal

velocity is greater after impact. Vertical velocity is

determined by coefficient of restitution not the spin.

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Two primary focuses

Performance

Vibration damping

(injury prevention)

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13/1413

Rebound power

is really

coefficient of

restitution.

Centre of stringimpacts onlysimulated.

Swingweight

is effectively

the moment of

inertia of theracquet.

Notice how

this is the key

factorrather

than simply

the mass of

the racquet.


14/1414

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