The 24-year-old, who scored two headers in the 3-2 win against AC Milan in the Champions League last week, took his tally for the season to 27 - with 19 of those goals coming in his last 19 matches - after netting twice more with his head in the 3-0 victory over West Ham on Tuesday.
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And he told FourFourTwo that he has practiced the timing of his runs to the extent that being in the right place at the right time has now become second nature.
"My heading's got better, just by working on my timing on when I meet the ball in the air," he said.
"Once you've got into a routine, it's muscle memory, your body takes over and it becomes natural."
And the Red Devils' goal-machine believes that the absence of former FIFA World Player of the Year Cristiano Ronaldo is one of the key reasons behind his higher number of headed goals, with new recruit Antonio Valencia supplying a more direct style of service than the Real Madrid superstar.
"When Ronaldo was out wide, you knew he would come inside and shoot, do a few tricks.
"Now with Valencia, you've got to be on your toes in the box because he will move in and cross it more than Ronaldo did."
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