The sportswear retailer posted revenues of $1.2bn (£800m) in its third quarter, a 28 per cent increase on last year's $938m.
Under Armour heralded the "game-changing" performance of many of its sponsored athletes, as apparel net revenues grew 23 per cent to $866m and footwear sales jumped 61 per cent to $196m.
The American company has now upped its already-bright outlook for the full year, bumping its anticipated revenues from $3.8bn to $3.9bn, and remains firmly committed to its target of $7.5bn in revenues by 2018.
Shares in Under Armour, which have risen 46 per cent in the last year, have jumped around two per cent in pre-market trading.
Why it's interesting
Under Armour may have been a late entry to the sportswear manufacturer race, but it is rapidly gaining ground on the two global giants.
The group's share price has risen 46 per cent in the last year to $99.2 per share, giving it a market capitalisation of $21.6bn. In contrast Nike (a much bigger company worth $112.8bn) has endured sluggish growth of just 11 per cent in the past year.
Under Armour has expanded into one of Nike and Adidas' strongest sectors, footwear, and enjoyed 61 per cent growth.
It is also aggressively moving into a number of new sports such as rugby and football - Under Armour sponsors teams in both the Aviva Premiership (Wasps) and Premier League (Tottenham Hotspur).
Jordan Spieth, the face of its first golf range, sent the firm's share price soaring when he won the US Open and Masters this summer.
What Under Armour said:
Our ongoing success in 2015 has been driven by innovative, head-to-toe product, combined with game-changing performances by our athletes.
Leveraging these great successes throughout 2015, our current Rule Yourself global marketing campaign highlights the training and dedication that drives our athletes to be their best on the biggest stages.
- Chief executive Kevin Plank
New sports, new markets and new shoes - Under Armour's growth is reflected in its record revenues.