Rory McIlroy says he's feeling leaner and more energised upon his return to golf

Rory Mcilroy returns to action at the Abu Dhabi HSBC Championship on Thursday

Rory McIlroy admits he has become a nightmare for restaurateurs as a result of the lifestyle changes adopted during a three-month golfing sabbatical.

The 28-year-old's break from the game ends on Thursday at the Abu Dhabi HSBC Championship. The tournament marks the start of a heavy playing schedule which he hopes will help him add to the four major titles he has won to date.

In the 104 days he has spent away from the game, McIlroy has gone through a prolonged period of self-analysis, physical training and range time. He believes he has found the formula to fully equip his challenge for the game's biggest prizes.

He is vowing to arrive earlier at tournaments and play more regularly having taken steps to acquire the energy to cope with this heavier workload.

McIlroy insists that a minor heart issue is "nothing to worry about" and that an improved diet has left him ready to take on fellow competitors he has enjoyed watching on television over the last few weeks.

"It's been nice, I've really enjoyed the time away from it but I must say I'm excited to be back," McIlroy told BBC Sport here in the Middle East.

"I'm probably a bit of a pain in the backside for waiters trying to order something and asking 'can you do it this way or cook it without any oil or any butter.'

"I've been quite disciplined with it. Obviously I let myself go on Christmas Day and Thanksgiving. But it's been really good and it shows.

"I feel better, I am a bit leaner and energy levels are probably a bit better and hopefully that'll affect how I perform on the golf course."

McIlroy carries the air of a student having used a refreshing summer vacation to gain resolve to knuckle down for final exams.

Johnson, Spieth and Thomas have all been successful recently, can McIlroy challenge the Americans?

Of course, this is not a now or never moment in his career but there is an unmistakeable imperative. He is fully aware of the high standards currently being set by the likes of Dustin Johnson, Jordan Spieth and Justin Thomas.

The Northern Irishman trails in the wake of these dominant Americans, having slipped to eleventh in the world rankings and he has been keeping tabs on their progress.

"I was just happy watching," he told me. "Mentally I was in a good place where I didn't feel like I needed to be out there at all.

"I was concentrating on what I needed to do but at the end of the day I'm still a fan of golf and I like watching and like keeping an eye on what everyone is doing.

"I watched quite a bit of golf in my downtime, obviously I played a little bit too and everything feels good."

McIlroy believes he can give himself better chances in events by arriving earlier at venues than he has done in recent years. "I'd turn up on Tuesday afternoons, hit a few balls, play the pro-am Wednesday and go," he said.

"I think, looking back on it, I'm going to try to get to golf tournaments a bit earlier. Try to get in on a Monday and it just gives you an extra day to prepare on the course, get used to green speeds, rough lengths and firmness of everything."

But he is adopting a more balanced approach to life in general. "I feel like you can still be really dedicated to what you do and still have time for other things. I think that's been the big thing because I'm sort of all or nothing in everything in life," he said.

"And I feel like I've learned a little bit of balance over the past three months in terms of still enjoying myself and being able to make the most of free time but still putting in the time you need to hopefully be the best golfer I can be.

"Sometimes I feel that I have to do too much and sometimes you don't have to, sometimes you have to work smartly and in the right way.

"It's almost better taking that approach rather than saying 'okay, I'm going to spend eight hours on the range'. That isn't productive, if you spend two quality hours on the range you can get more out of that."

McIlroy has described his minor heartbeat irregularity as 'not that big of a deal'

McIlroy made headlines last weekend when he revealed he is being monitored for a minor heart irregularity. "It's definitely not a heart scare," he smiled.

"But in fairness it is scary when a heart doctor does ring you and say we've found something. But it is no big deal at all.

"I think if you tested the majority of the population they're going to find something that's a bit of an abnormality. It's just a little thing to keep on top of but definitely nothing to worry about."

More pertinently for someone who says it was "a relief" to be able to take three months away from the game, he seems to have the heart to rededicate himself to his golf career.

"Look, I want to win golf tournaments again," stated the man whose last victory came at the Tour Championship in September 2016.

"But you have to play them to give yourself a chance to win them in the first place. I'm playing quite a lot this year, so hopefully I will give myself plenty of chances and the more I give myself the more comfortable I will be in that position again.

"Hopefully I can start the year in the right way. I really missed the competition part of it.

"I'm as excited for a season more than I have been for a long time because of having that bit of time off and having time to reflect on things.

"I love what I do, I love being out here, I love playing golf tournaments and hopefully I can show that excitement on the course."

Fuelled by a healthier diet, it certainly seems McIlroy has rediscovered his appetite for competitive golf.