tennis biomechanics
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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
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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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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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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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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.
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