The Manchester United youngster has endured a largely frustrating season under Dutch coach Louis van Gaal, who was appointed as David Moyes’ permanent successor last May.
Januzaj has started just seven Premier League games since the 63-year-old took charge at Old Trafford, making a further nine appearances from the bench.
However, the Belgium international, who was linked with a loan move to Paris Saint-Germain in January, is determined to become a better player after a tough season.
“I do a lot of work in the gym. I am trying to be faster and stronger so I can be tougher when I go out on the pitch,” Januzaj told United’s website.
“I am doing a lot of short, sharp stuff so, when I turn a defender or go past a player, I can just get a few metres away from them with my acceleration.”
The 20-year-old Belgian star was a second-half substitute as United lost 2-1 to Arsenal in their FA Cup quarter-final tie at Old Trafford on Monday night.
Januzaj, who signed a new long-term deal in October 2013, has scored four goals in 43 Premier League appearances following his top-flight debut.
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