FRANKFURT, Germany — German sportswear firm Puma plans to keep spending on marketing and on winning endorsements from star athletes, its chief executive said, seeking to revive a brand that still lags behind market leaders Nike and Adidas.

"We are not going to decrease marketing. It will always stay between 10 percent and 12 percent of sales," Bjorn Gulden told journalists after the company published full second-quarter results.

Puma's operating expenses rose 11 percent in the second quarter as it spent on marketing and retail, but demand for new high-margin shoe models still helped more than triple its operating profit (EBIT) to €43.4 million ($50.5 million).

Earlier this month, the group hiked its guidance for 2017 sales and operating profit as it announced a 16 percent jump in currency-adjusted second-quarter sales.

By Maria Sheahan; editor: Victoria Bryan.