He couldn't dismiss the severe headaches, vertigo and balance issues that five concussions in the space of a year on the rugby league field had caused.

Playing for Hull Kingston Rovers in England at the time, Heffernan was excited. Last year's Magic Weekend was approaching, and the Junee product's family was flying over for the spectacle at Newcastle.

But the 24-year-old knew his brain was giving him signals he couldn't ignore.

"I was driving to pick up my brother and cousin to come and watch the game, I had a banging headache and could barely see the road," the former Canberra Raiders and Penrith Panthers lower grader said this week.

"I pulled over and was pretty emotional to my family and said I'll have to pull out of the game.

"I hadn't told anyone at that point exactly how I was feeling, because I knew if I told people close to me they'd encourage me to report that."

The outside back copped a serious knock against St Helens, took some time off then suffered another against Widnes.

Specialists set Magic Weekend as his return target, and Heffernan was determined to play.

"Once I had pinpointed that date I was doing everything I can to play that day," Heffernan said.

"While I wasn't getting symptoms at training, I was getting delayed symptoms. Three hours later I could be at home and get a banging headache, wouldn't sleep at night and be in all sorts.

"I rang our physio mid week and said 'I'm done here, I'm not playing this weekend'."

If Nigel Plum stuck to his word, he wouldn't be in the NRL's 150-game club.

With four games to go in his final season in 2015, he told his wife Nic that if he suffered one more head knock, he'd hang up the boots.

"I actually had a head knock at the captain's session before my last game. It was my 150^th, I didn't want to finish on 149," Plum said.

"You've only got one brain and you can't really fix them once you bugger them up, that was why I retired."

After several concussions during his career Plum, who now works with indigenous youth at Griffith, had to give the game away.

He misses playing but had to put his wife and three young children first.

"All I wanted to do was come back and play for (junior club) the (Wagga) Kangaroos, I had it teed up, but the head issue put a stop to that," he said.

"I've got three young kids, that's a big reason I gave it up so I could have a good quality life with the kids.

"I miss playing but at the end of the day the family's more important to me."

Plum began to take concussion more seriously when he failed to recall a long phone conversation he had with his wife in 2015.

"That scared the shit out of me," Plum said.

"I got knocked out against the Raiders, had a week or two off then played Melbourne. After that game I had conversations with the Panthers assistant coach at the time (David Fairleigh), then had a big conversation about it with my wife.

"Two weeks later I brought it up again with her because I had no recollection of it. It was scary at the time."

Heffernan doesn't want his story to deter people from playing rugby league. He's using his experience to delve into the issue further, and use the information to help others.

He is about to submit a research paper through his Masters of Sports Rehabilitation studies with the University of Melbourne.

"I've just done a research study in line with the NRL and the clubs on their assessment protocols for concussion diagnosis, and how they can keep improving it," he said.

"I do talks with junior representative teams. It's a tough area because it's still a growing topic and all the publicity that's come out (about concussion), hopefully it keeps sparking the attention it deserves.

"A personal story you hear firsthand makes a big difference. The NRL are doing a great job in the things they're bringing in, it just needs to continue in that trend."

Fifteen months on from his last head knock, Heffernan is still on a high dose of medication each day to manage symptoms.

His head knocks affected his vestibular system, in layman's terms the connections to his brain. Unfortunately, many concussion assessments are limited to testing your cognitive function.

"My last concussion was April 7 last year and I'm still having those symptoms every single day," Heffernan said.

"The vertigo and disorientation with where you are is probably the biggest one for me.

"The testing is very neuro-cognitive based. That's only my opinion, but the research has backed it up as well that there's a need for a more holistic test which covers each of those (brain) systems.

"I slipped through the cracks in some respects. If it comes up the first time I've damaged the vestibular system, my (quest to) return to play is completely different.

"I've done the research now and I want to keep educating people and these conversations spark investigations into what we need to do differently.

"I don't blame anyone at the medical staff there (Hull KR),they were just following protocol, but long term we have to get that protocol right and we'll get there."

Heffernan said the system won't work if players shirk their duty to take it seriously.

"I was doing better in the baseline tests after the concussion then what I was before it," he said.

"That's common because when players do the first one (during pre season) no one really cares, they just do it because it's protocol.

"If I knew what I do now, the choices I would have made would have been totally different and that's my reasoning for trying to educate.

"I don't expect people to know the ins and outs, but hopefully they take home the message of being honest with their symptoms.

"What I found through my studies is a lot of the current assessment methods are subjective and players have to report their symptoms (for it to work). The onus through our education stuff is to relay to the players how important it is to be honest.

From my point of view, in the future it would be great if those assessments could be more objective and taken out of the players' hands.

"I'll definitely be relaying what I've found (to the NRL). I've worked with some clubs and a lot of players reported they wouldn't be honest with their symptoms, purely to return to play."

The NRL's handling of concussion has improved markedly in the four years since Plum retired.

"They know a lot more and are putting a lot more measures in place," Plum said.

"When you do get concussed you don't think straight, you can't think straight.

"It's good in today's game they're taking the decision away from the player. For most of my career the trainer would ask you 'are you alright?' and you'd say 'yeah, I'm alright'. Half the time you had no idea what was going on.

"They're dealing with it a lot better and that comes from having knowledge and the research they've done."

The NRL paid for Plum to be assessed by Melbourne-based concussion specialist Paul McIlroy.

His first assessment in September, 2015 came back all clear, and received another positive report in a follow up check 18 months later.

He is due for another soon, and has agreed to a request from the university of Newcastle to assist in their research into the issue.

"I'll go up to Newcastle, have a brain MRI scan done and do some cognitive tests," Plum said.

"I guess (I'm doing it) for peace of mind. Yes, I've been given the all clear initially, but the concern is the retired footballers who have brain damage now, did they have it the first few years after they quit football? That's the unknown.

"I'll continue to be tested every 18 months or two years, and do that consistently to see what changes, if any, are occurring."

Heffernan said the uncertainty surrounding concussion recovery is the toughest thing to accept.

"There's no definitive trend, one day you could be walking around, going to a movie, shopping and doing things very stimulating to the brain, and you feel fine," he said.

"The next day you could do absolutely nothing, and you have a shit day. You never know what you're going to get and that's the hardest part, it eats away at you and debilitating is the perfect word.

"There's no set thing that sets it off, it's very hard to track. There's management things like staying off screens or things that stimulate the brain, but aside from that there's no magic pill."

Heffernan's personal experience strikes a chord with the teams he speaks to.

"When I tell my story, when you hear people retire (young) and you can speak to that person, it has an impact," he said.

"It's an eye opener to see how it's managed at that grass roots level and I know they don't have that testing, which makes it hard. That conservative approach is the best way forward.

"I'm aspiring to work as a performance and rehab coach, hopefully these experiences with concussion will help me as a coach."

Country Rugby League regional manager, David Skinner, said concussion management in the bush has vastly improved, but still has a way to go to fully eradicate the culture of not letting down your teammates by leaving the field.

"We still don't think all the trainers are on board with their level of responsibility," Skinner said.

"Only this week we sent out a couple more notices and it happens on weekly where we hear of an incident where a trainer lets a (concussed) player go back on.

"We're not the NRL where the doctors do an assessment, once they've had something they're off (for the rest of the game).

"We've still got a bit of old school mentality where they're putting them back on. We want them to live long and healthy lives, and not have ramifications. we can only push even more that they continue to be restrictive in making sure we don't let players come back on.

"The majority of games it's word of mouth and we've put it out to the clubs to be responsible, to make sure you take pride in ensuring you're looking after your players, and I think most of them do.

"Of all the winter sports we've got the hardest hurdles to jump, the highest standards for (trainer) accreditation for anything.

"We trust if a trainer's done all that accreditation he takes pride in his workmanship and clamps down on things like concussion."

Heffernan urged bush footballers to take a long term focus when dealing with concussion.

"It's about educating people to be honest and missing one or two weeks, as opposed to missing the next ten or 12 years of football, is the big thing."

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