MELBOURNE is reaping the benefits of its controversial low-carbohydrate, high-fat diet, with players returning to the club in 2015 leaner.

The players embarked on the diet in October after a visit from Tim Noakes, a South African professor of exercise and sports science who is a huge advocate of the eating plan.

Demons turn to fat for fitness

Melbourne's elite performance manager David Misson told AFL.com.au in November the club was adopting the diet to give it a "competitive edge".

While some experts have backed the diet, it has also drawn criticism from some dieticians and doctors.

However, it appears to be working at Melbourne, with players returning to the club after the Christmas break sporting leaner physiques.

The benefits of the diet were also on display during Friday's 3km time trial at Princes Park, with many Demons running personal bests. 

Key defender Tom McDonald crossed the line first, ahead of Rohan Bail and Jordie McKenzie.

Jack Grimes finished fourth, second-year Dee Jay Kennedy-Harris fifth, and veteran Daniel Cross sixth.

Midfielder Bernie Vince said it was hard committing to the diet over Christmas, but he too had noticed a change in his body shape.

"I gave myself one or two days [off] over Christmas," Vince said after the time trial.

"Everyone's doing well with it, a lot of guys have lost a bit of weight but not losing any strength, so I see it as a positive so far.

"I don’t feel any less energised and I'm a bit lighter myself as well, so hopefully that can transfer into some good results during the season."

The diet, which is a form of paleo but not as strict, is becoming more common among athletes, with Australian all-rounder Shane Watson an advocate. 

In the US, NBA superstar LeBron James lost a significant amount of weight on a more extreme version of the diet but dumped it after 67 days.

Vince said the players would be sticking it out a little longer then James. 

"If LeBron's given it up, I'm giving it up," Vince joked.

 "I think it's going to continue though - we've been doing it since the start of October so I can't see why we'd go off it.

 "The night before a game though, we might have a bit more carb intake but not much difference." 

It was a hotly contested time trial on Friday, with plenty of jostling at the start line. 

The group set a cracking pace, but McDonald eventually won comfortably ahead of Rohan Bail and Jordie McKenzie. 

"It's pretty impressive, the way the group has come back but we expected nothing less," Vince said. 

"We've got some elite runners in our group so now it's just transforming that into game-day running. We're in good shape, just need to transfer it to games. 

"There was some pushing and shoving in the start, and (Jack) Grimes nearly went down. 

"It’s the competitive nature I guess. We've been trying to embrace [it] over the pre-season - so far it's coming out in everything we do. There's some pretty competitive beasts in our group." 

Demons skipper Nathan Jones, who cut his heel in a surfing accident at the weekend, watched from the sidelines along with injured midfielder Jack Trengove. 

Trengove is still on crutches and his left foot still in a moon boot after surgery late last year on his navicular. He was able to take the boot off while he holidayed in Bali, but will need to continue to wear it for the next few weeks at least. 

Jack Watts did not run the time trial, due to being on restricted duties, while forward Jesse Hogan was also absent despite training with the main group on Monday.