Risk of motor neurone disease six times higher for footballers Heading ball may be to blame

It has claimed the lives of a number of former players, including Don Revie, the former England manager, Rob Hindmarch of Derby and Sunderland, and Middlesbrough's Willie Maddren.

Researchers at Turin University in Italy surveyed the medical records of 7000 footballers playing in the country's Serie A and Serie B between 1970 and 2001.

They found players were vulnerable to a particular type of motor neurone disease (MND) known as amyotrophic lateral sclerosis (ALS), which involves the death of motor neurones, the nerve cells responsible for voluntary movement.

The condition eventually leads to paralysis and death.

It could be a result of players repeatedly heading footballs, the study said.

Researchers pinpointed the average age of diagnosis among footballers for the disease at 41, about 20 years earlier than usual.

They also found that the longer the sportsmen played football, the greater the risk.

Based on the normal incidence of ALS, the cause of which is unknown, and the players' ages, Dr Adriano Chio and colleagues said there should have been an average of 0.8 cases in the group studied, but instead they found five.

Dr Chio said the high incidence of the condition among players could be related to football-specific trauma such as heading the ball, strenuous physical exercise, the use of drugs both legal or illegal, or even environmental chemicals such as herbicides used in football fields.

It has been established that brain injuries caused by blows to the head can lead to Alzheimer's disease in later life.

However many of the studies attempting to link heading a football with mental impairment have been, at best, inconclusive.

Celtic's Billy McPhail, who died in 2003, had fought a long battle to prove his long-term dementia was a direct result of his heading prowess.

Dr Brian Dickie, director of research at the Motor Neurone Disease Association, said there was some anecdotal evidence of a link between high levels of physical exercise and an increased risk of developing MND.

However, he added that more research had to be carried out before conclusions could be drawn.

"This study does appear to show an increased risk of Italian footballers developing MND, but we still don't know what causes this link, or whether it would be ref lected in other groups of footballers and sportspeople, " he said.

The research was published in Brain and reported by New Scientist.

It was prompted by what the Italian press dubbed "the motor neurone mystery" - the discovery a few years ago of 33 cases of ALS during an investigation of illicit drug use among 24,000 professional and semiprofessional players in Italy.

In the US, ALS is known as Lou Gehrig's disease after the baseball legend who was diagnosed with it in 1939.

Clusters of cases of ALS have been reported in American football, but until now no large-scale studies have found any clear link between sport and a high incidence of the condition.

ANATOMY OF A DISEASE

Every day in the UK, three people die from motor neurone disease (MND), and it affects up to 5000 people in the UK.

MND is a rapidly progressive and fatal disease that can affect any adult at any time.

The motor neurones are the nerve cells which control muscles. As the motor neurones die, the muscles stop working.

The cause of MND is unknown and there is no cure.

The disease was first described in 1874 by Jean-Marie Charcot, a French neurologist.

MND leaves people unable to walk, talk or feed themselves but the intellect and the senses remain unaffected.

Death is normally as a result of respiratory failure but with the right palliative care is peaceful and pain-free.

Average life expectancy is 14 months after diagnosis.

People who have died of MND include David Niven, Don Revie, Leonard Cheshire and Jill Tweedie. Professor Stephen Hawking has survived with MND for more than 30 years.