tennis biomechanics

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  • 8/11/2019 Tennis Biomechanics

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    1

    !"#$%&'( *+''&,

    - .&"/+$%#'&$#0 12".0+/3

    F = ma

    Ft= m"v

    " = #$

    "t= %#&

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    #'8 *+''&, 92&1,

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    2

    :2&,6 40+;"2,

    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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    3

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    4

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    5

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    6"1 6"52 10#7+2,S Racket

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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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    7

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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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