Adidas AG's (ADDYY) resurgence over the past year is thrashing its American competitors Nike Inc. (NKE) - Get NIKE, Inc. (NKE) Report and Under Armour (UA) - Get Under Armour, Inc. Class C Report , with both falling in Thursday premarket trading.

The German sportswear company, which in recent past had looked to be put in the annals of history next to the VHS, reported sales in the second quarter increased by 18% to €5.038 billion ($5.96 billion). The company also reiterated its improved full-year forecasts, with the group now expecting currency-neutral sales of between 17% and 19% and a 0.8 percentage point improvement in gross margins to 50%.

Adidas dominance has sent its shares up more than 27% since the start of the year, compared with a more than 17% rise for Nike and a 36.1% loss for Under Armour.

It is on the home turf of Nike and Under Armour where Adidas is making its gains. The German sportswear company saw sales in North America up 28% to €1.014 billion, compared with Nike which saw sales in the U.S. flat in its last fiscal quarter at $3.753 billion. Meanwhile Under Armour on Tuesday, Aug. 1, reported sales in the region were up just 0.3% to $829.8 million.

Adidas runaway success has come in the running segment where it saw double-digit increases and has been unable to keep up with demand for its springy Boost shoes.

Adidas doubled its share in the U.S. sport footwear market to 12.7% in April, while Nike slipped 2 percentage points to 52.7%, market intelligence firm NPD said, with Adidas taking three of the top spots in the 10 best-selling shoes.

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Under Armour, which doesn't divide out its earnings by sport, said Tuesday that its footwear segment saw sales fall by 2.4% to $236.9 million.

For their parts Nike and Under Armour have this year both announced restructuring programs. Nike in June said it would cut about 2% of its global workforce and eliminate a quarter of its shoe styles, to better compete in a slowing market. It also announced a deal with Amazon AMZN to sell its products directly through the site, something Adidas already had in place.

Meanwhile, Under Armour said it would cut jobs and close stores. Adidas has already undertaken such restructuring ridding itself of its golf and hockey brands to focus on its core offerings.

Nike shares were down 0.49% in premarket trading Thursday, expected to open at $59.50. Shares have gained 8.57% over the past three months. This far outweighs the 12% decrease in share price for Under Armour in the same time period, which saw shares close at $16.47 on Wednesday.

Under Armour shares were down 1.13% in premarket trading and expected to open at $18.35.

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