A SURPRISE growth spurt is propelling young Bulldog Jackson Macrae towards his goal of becoming an inside midfielder.

The 19-year old has grown an impressive three centimetres since his arrival at Whitten Oval just 12 months ago.

Originally listed at 188cm and 75kg, Macrae has worked hard in the gym, piling on 10 kilograms of bulk over the past year.

"I've been fortunate enough to grow a few extra centimetres," Macrae told AFL.com.au.

"I'm about up to 190-191 now. So now height, hopefully I'll stay about the same, and get a bit bigger as well.

"It's about 10 kilos now since I got drafted a year ago. I think they're looking to taper that off a bit now. I'm about 84kg now, so I'll stay around there until the start of next year, and start to work it up over the next few years."

Tall, strong midfielders have become highly sought after in recent years, after the sustained success of Fremantle's David Mundy (192cm, 91kg), Sydney Swan Josh Kennedy (188cm, 96kg), Collingwood's Scott Pendlebury (191cm, 91kg) and Essendon skipper Jobe Watson (191cm, 95kg).

Macrae's body has held up well during the steady transformation, and now he believes he has the size to match it with the best in the middle of the ground.

"I guess it was to see how my body reacts to the lifting and see how I go with soreness and stuff. It's responded really well, fortunately, and I'll just keep taking it as it comes," he said.

"I guess I'm looking to play a more of an inside role as well, and not just stay on the half-forward flank or the wing. I'm working with Kingy (Stephen King) and Joel Corey, who's recently joined us.

"I think naturally I've grown up more of an outside mid, but I think I've got the capabilities to play inside and outside as well, which will really help the club."

Macrae played 13 senior games in 2013, and coming into his second season, he's starting to show his leadership at the club.

"I think naturally just being a bit older you come out of yourself a bit more, and are a bit more vocal around the club and on the track," he said.

On a formal leadership role, Macrae said: "Not for a few years I'm guessing, but I think leadership is something we all should aspire to."

In the meantime, Macrae is busy taking the first-year players under his wing.

"I've spent quite a lot of time with (No.4 draft pick) Marcus Bontempelli," he said.

"He doesn't have his licence, and I didn't have mine this time last year, so I've been driving him around a bit and looking after him. Hopefully he becomes a really good player for the club."