Even seven-time Grand Slam champions need to mix things up sometimes. (AP Photo)

In a word: plyometrics. Being one who loathes long-distance running, which isn't terribly conducive cross-training for tennis anyway, Venus Williams opts for a mix of jump exercises (the aforementioned plyometrics) and typically performs the moves early in a workout, when muscles are fresh, per Self magazine. 

"It's a lot more intriguing and makes the time go by a lot faster," Williams says of performing 10- to 15-minute plyometric routines in lieu of long-distance running.

The 36-year-old, a 2017 Australian Open finalist, likely works out in her eponymous EleVen by Venus brand of athleisure wear. Alongside playing in the impending BNP Paribas Showdown at Madison Square Garden, she will outfit all female staffers at the event in EleVen styles, which lean heavily on black-and-white coloration but include pops of pink and more accent colors. The line went live for sale in mid-February and will be featured in tennis clubs stateside for months to come.

As for those MSG staffers, no word yet on whether they will receive everything on down to EleVen brassieres. 

Ahead of the showdown event, where she will face off against the friendly fire of Garbine Muguruza, Williams quipped, "We have a joke that our bras fit every woman in our office."

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