• Greg Smith is director of Wintec's centre for sport science and human performance director. He played hooker for the Chiefs, has coached Waikato and played test rugby for Fiji.
There has been serious attention paid to concussion in sport recently.
Rugby has received a lot of this attention in New Zealand.
As the game has evolved the athletes have become larger, stronger and faster. I would estimate that professional athletes are now at least 10kg bigger than when I entered the professional game in 1996. Rule amendments have resulted in the game becoming faster and the contact intensity has magnified.
The recent focus on concussion within sport has brought much needed attention to an injury that struggles to be understood.
Concussion is an invisible injury. The effects can be varied and it's difficult to understand.
Most injuries have simpler prognosis and treatment plans. Tendons reattached, joints replaced and muscles repaired. Concussion is more complicated with a far greater range of symptoms and possible outcomes.
I know from experience that recovery from concussion is complex. Repeat concussions ultimately finished my rugby career at 30. It was a result of 20 years of head knocks that started at 10. I would frequently take knocks to my head that resulted in loss of memory. As a young boy I started to be known as the guy with a hard head. I fed on this and continued to knock my head around in an attempt to embellish these perceptions.
My introduction to senior club rugby was met with a knock that resulted in four weeks of severe headaches and vomiting. As I got older, finals rugby, Ranfurly Shield challenges, Super Rugby games and test matches were all played under the cloud of concussion.
I was selective about how I reported what was happening to me. I knew the significance of each injury was hard to measure and that I could control the medical treatment plan and the extent to which game time was missed depending on what I told medical staff.
Many times I went straight back out. I didn't want to give up my spot.
Towards the end of my career I suffered a series of knocks that proved to be game changers. For the first time the symptoms scared me. Previously, I had told myself that I was invincible. Rugby was my identity and I derived self-worth out of being Greg Smith the rugby player.
It was the extent of lost function that scared me. I temporarily lost the ability to speak. As speech returned I realised I had forgotten words I once knew. I couldn't sit in a room with the lights on.
Anything that required sustained concentration wasn't possible. I couldn't concentrate for longer than a minute. I couldn't sit at a computer or drive a car. Noise was intolerable. I was intolerant. But, I continued to play.
During 2004, my last year of rugby, I saw four or five different brain specialists. I was looking for the doctor who would tell me I could continue playing, but they all told me it was time to stop. I was told that any further damage would result in the permanent loss of brain function and that the risk of suffering a stroke from a head knock was high.
By the time I gave up, my symptoms were worse. MRI scans showed scarring in my cerebellum, the part of the brain responsible for functions such as language, attention and co-ordination.
When my brain became overloaded it would go into spasm and I would experience nystagmus - a condition in which my eyes would blink uncontrollably. I was also diagnosed as having post-concussive depression.
I was lucky I stopped when I did. I had made poor choices that led me to the brink of permanent disablement. It has taken years to rewire my brain and a great deal of awareness to manage my symptoms, some of which haven't gone completely.
Everyone who plays rugby understands that there's a risk of being hurt, but what I advocate is making good choices when injured. And while personal responsibility is important, young athletes might require others to help the decision making process.
Be aware of what you are experiencing, and report it honestly to your doctor.
Remember that it's only a game, and while it's important, it's not the be all and end all of who you are and all you will achieve. Being an athlete is not your identity, it's just something that you do for a period of time.