HERZOGENAURACH, Germany—Puma SE said Tuesday it would launch a multiyear partnership with pop star Rihanna as part of the athletic-apparel maker’s attempt to burnish its faded image.

Starting next month, Rihanna will become the German brand’s “global ambassador” for women’s fitness and serve as its creative director for women’s products, the company said. She will directly influence the product-design process starting as soon as this spring, Puma said.

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