Unscrew the Light Bulb (on the serve)

I learned this method from Don Kerr, former Tulane tennis coach, but interestingly a badminton coach who brought his material to the tennis world.
He and I developed the Whistler, a biomechanical teaching aide, which led me to a Masters program at the University of West Florida where I studied motor learning as applied to teaching the tennis serve.
Don described the last two elements of the serve as
  • Throwing a dart in the ceiling – in order to swing up rather than forward
  • Unscrew the light bulb – meaning all the forearm rotation occurs at the top of the swing
Far too often players think and swing “forward” in their service motions.  But in another method the action is not forward but up – and the unscrewing or forearm rotation is what drives the ball forward.
The sequence below shows the hitting action for a badminton clear – which is the precise “up and out” snapping action.
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  • Adrian

    Reply Reply March 28, 2020

    Jim, I’ve followed your tips through the years, and I think they’re great. I use similar analogies when I teach my students. I generally take them through a ‘pronation’ from the elbow, before going to the ‘bulb.’ I agree with everything you say about Sampras, including what you demo with your ARM before you show it with your racquet. IT looks to me that when you are doing that latter you are not extending the arm fully, i.e. to throw the dart into the ceiling, then unscrew the bulb THEN rotate/pronate from the elbow. With unchanged admiration and respect. Adrian

    • Jim McLennan

      Reply Reply March 28, 2020

      Adrian – thanks for this note where do you teach it would be fun to compare notes – my current project is attempting to prioritize a fluid overhand throwing motion first before anything is done on the serve – what do you think of that? Jim

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