Flying through the air at 50 kilometres per hour headfirst towards a field of rocks was never the way ABC newsreader Peter Gee wanted to test his faith in bike helmets.

The long-time anchor of Tasmania's ABC news bulletin had embraced the virtues of wearing a helmet since he was a boy.

But lying in hospital with two fractured neck vertebrae, Gee shuddered to think what might have been if he had been riding without a helmet.

"As it is I've got a spinal injury, and luckily, after the operation, apart from a stiff neck, once I've recovered I should be fine," he said.

"But I'd rather that than the potential of a brain injury, which would have been well on the cards."

Entering through the side of Gee's neck, the surgeon bound the two vertebrae. ( Supplied: Peter Gee )

Gee's accident did not involve another vehicle, an angry motorist or a pedestrian — his was one of the 48 per cent of on-road bicycle crashes that involve no other road user.

Descending a steep Hobart backroad behind friend and pro-rider Nathan Earle, Gee got lost in the joy of the ride only to pay for a brief lapse in concentration.

"I've been down this road lots of times and I know how steep it is," he said.

"And it's rough, so I usually take it very gingerly.

"But we'd had such a fantastic ride. Nathan was ahead of me. I was admiring how well he was descending and not concentrating."

Before he realised, Gee had entered a tight corner too fast but still thought he could wrest back control.

But the brakes locked up, the corner tightened even more and he shot off the verge and over the handlebars.

A paramedic was on hand within minutes of the crash. ( Supplied )

Gee crashed headfirst into a rock, the contact point being just above his right ear. The right side of his body took a beating — shoulder smashed and a four-stitch wound sliced into his knee.

He was knocked out briefly and came to thinking he was at home in bed. He soon realised he had crashed.

"I could feel the pain my neck straight away, so I didn't move," he said.

The foam casing was cracked through in five places. ( ABC News: Gregor Salmon )

"I was worried about my neck. I had all movement — I knew I wasn't paralysed; no pins and needles."

The impact dented the outer shell of the helmet and left five cracks in the protective foam.

After waiting in vain down the road for his companion, Mr Earle doubled back up the hill.

He called an ambulance as well as paramedic friend Keith Macqueen, who happened to be on his way to work and was there in minutes.

"I had expert help within a quarter of an hour," Gee said.

A week later, with his neck ligaments too damaged to regain their strength, a spinal fusion was performed on his C2 and C3 vertebrae.

The disk in between was destroyed.

Viewers will not see Gee anchor the news again in 2017 but he hopes to be back in the chair in early 2018.

And he will be back on his bike sooner, if his recovery allows.

Call for optional helmet use to attract more riders

The point of impact was above Gee's right ear. ( ABC News: Gregor Salmon )

A long-time supporter for compulsory helmet law, Gee never wanted to be a crash-test dummy to prove a point but he riles at recent efforts to make bike helmets optional for riders.

The Bicycle Network, Australia's largest bike-riding organisation, recently declared it was open to reviewing its support of mandatory helmet use.

They ran an online survey to help assess their position.

"At the end of the policy review, we may or may not change our position — it all depends on what we find," their website reads.

Among reasons given to relax the law is the belief that riding a bike is not necessarily a high-risk activity, that the mandatory law has had a negative effect on participation, that fines for non-compliance are a further disincentive and a questioning of the pro-helmet safety evidence.

That the Bicycle Network would countenance reviewing its support on mandatory helmet use riled Gee. ( Supplied: Bicycle Network )

In her submission to the Bicycle Network survey, Professor Kay Teschke from the University of British Columbia in Canada wrote:

"The benefits of cycling are high and the risks are low. Our Canadian research indicates absolute risks of cycling fatality and serious head injury are low: the risk of death is about 1 per 7 million trips by bike, the risk of hospitalisation for head injury is 1 per 640,000 trips by bike. "Studies consistently show that the individual health benefits of cycling greatly outweigh injury risks. "It is important to population health to make it easy for more people to cycle more often."

But in his submission, Associate Professor Jake Olivier from the University of New South Wales supported the mandatory rule:

"The reason I support bicycle helmet legislation is because the peer-reviewed research evidence indicates: "1. Bicycle helmets are highly effective at mitigating head, serious head (roughly skull fractures and/or intracranial haemorrhage), fatal head, and facial injury "2. Helmet wearing rates are low without helmet legislation and high with them "3. Bicycle helmet legislation is associated with declines in cycling head injury and cycling fatality."

Keeping mandatory rule a 'no brainer'

The fact the Bicycle Network even expressed a willingness to review their position was enough for Gee to withdraw his support, deciding not to renew his insurance and take it elsewhere.

"I just cannot hold with that at all," he said.

"To even countenance going backwards — making it optional — is ridiculous."

Gee said you did not have to come off your bike at high speed to suffer a lifechanging head injury.

"I've fallen off in a car park when I went into a speed hump at about 5 kilometres per hour," he said.

"This speed bump flicked my front wheel sideways and I came off and completely shattered my helmet.

"I would have had a fractured skull without a shadow of a doubt but for the helmet, and that was the most innocuous thing you could imagine."

Both crashes only deepened a long-held conviction.

"It's a no brainer, if you'll pardon the pun — leave helmets mandatory."