Injuries among rugby players have almost doubled since the sport scrapped its amateur status five years ago, according to research published today.

Scottish doctors assessed injuries sustained in the 1997/8 season among 803 players in the Scottish borders, 30 of whom played professionally for Scotland or the local Border Reivers District.

The study was a repeat of research carried out in the 1993/94 season, when rugby union was an entirely amateur sport.

It found that in the four years between the studies, the proportion of players who sustained significant injuries had almost doubled, from 27 to 47 per cent even though fewer competitive matches were played.

There was one episode of injury every two matches, compared with one every 3.4 matches in the 1993/4 season.

Professional players sustained an even higher rate of injuries - one for 59 minutes of competitive play, or 1.4 injuries a match. For every hour of competitive play, each professional lost more than two days of training or play. Typical injuries were to muscles, ligaments, knees, hips and thighs. In half of the cases, the damage was caused by a tackle.

The authors strongly criticise protective equipment, such as ankle braces, padded headgear and clothing introduced after the advent of the professional era.

The protection may also encourage players to tackle head-on or with far greater force, inflicting injuries on their opponent or to themselves, the researchers suggest.

They lash the International Rugby Board (IRB), saying its "principal concerns" had been to market and manage the sport.