Research has found that training and playing contact sports at altitude lowers the rate of concussion by 30 per cent.

The study, published in Journal of Orthopaedic & Sports Physical Therapy, found that in the first 16 weeks of the 2012 and 2013 NFL season, 300 incidences of concussion occurred, involving 284 individuals (we pity those 16 players who got concussion twice).

The team behind the study, which took place at the University of Cincinnati in the USA, then analysed rates of concussion in relation to the elevation of the game.

Odds of at least one concussion were reduced by 32 per cent in games played at higher elevation. Playing at altitudes in cities such as Denver (Colorado), which has an altitude of 1600m above sea level, saw significantly less incidences of altitude.

It is suggested that this intriguing correlation os due to the increase in cerebral blood flow which happens whilst at altitude. In contact sports, most concussions are caused by the movement of the brain inside the skull. As the brain is not fit snugly inside the skull, the swift acceleration and deceleration of the head during contact points increases the movement of the brain inside it’s protective casing of bone.

The increase of blood to the brain cause a slight, non-threatening swelling of the brain, which leads to a tighter fit within the cranium, therefore reducing the risk of movement upon impact.

Further research in rugby would be interesting, as would discovering at what altitudes does the decrease in performance outweigh the benefit to lowering concussion.