Punching bag
A punching bag was a sturdy bag designed to be repeatedly punched for use in physical exercise or stress relief. Boxers commonly used punching bags for training. 

In 2373, Captain Benjamin Sisko used a punching bag (held by Jadzia Dax) to relieve some stress after Starfleet took him off of the Michael Eddington assignment – the first time in his career he had been taken off of an assignment. ()

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Sporting equipment