There's no denying that female tennis players, like Serena Williams, Maria Sharapova and Caroline Wozniacki, are strong, but their strength doesn't begin to rival their beauty, inside and out.
The Women's Tennis Association thinks so too -- today they kick off their "Strong Is Beautiful" campaign, which serves to expand the reach of women's tennis with the help of a few A-listers. Kelly Rowland, Aretha Franklin and Susan Sarandon are all invested in the effort -- and we've got the videos to prove it.
Check out what these beauties have to say about what strength means to them below:
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