Rugby teams have got taller and heavier over the past 20 years as the quest for 'supersize' players paid dividends, new scientific research shows.
The study of players who competed in six World Cup tournaments found there was a definite correlation between size and success.
Rugby might still be a game for all shapes and sizes at lower levels -- but apparently proving the maxim that 'a good big one will always beat a good little one', the study records a trend towards giant men in rugby.
The study by French researchers looked at the vital statistics and experience of all players who took part in World Cup matches between 1987 and 2007. It analysed these stats from teams that progressed in the tournament compared to those eliminated early.
No countries or players are mentioned by name in the research, although the Irish teams from all six tournaments were included.
It concluded the teams with the tallest backs, heaviest forwards, and longest time playing together have been most successful at the Rugby World Cup.
The data showed that weight progressively increased for forwards and backs, while height progressively increased for backs between each World Cup series.
The authors said the increase in physical confrontation on the pitch and the need to provide strength and power "leads to a quest for supersize players".
The research on 2,692 players, carried out by experts at the Institut de Recherche Biomedicale et d'Epidemiologie du Sport (IRMES) in Paris, is published in the British Journal of Sports Medicine.
A general trend was that forwards and backs in high-performing teams weighed around 4lbs more than their less successful counterparts.
One of the authors, Prof Jean-Francois Toussaint, said: "Given the constraints of the game, which directs the play towards more physical confrontations, rugby becomes a sport where heavy players become increasingly important."
"Simple factors such as mass and height are discriminatory in the armament race. In fact, teams with heavier forwards and taller backs perform better than others."
While there is more to rugby than mere height and weight, many of the most successful players in the current Irish team closely fit the templates outlined in the research.
The current captain and second-row forward Paul O'Connell towers at 6ft 6ins tall and weighs 17st 4lbs.
Brian O'Driscoll, stands 5ft 10ins tall and weights 14st 13lbs -- closely matching the average height for a successful back.
Ireland's all-time highest points scorer Ronan O'Gara is 6ft tall and 13st 2lbs. And his centre colleague Gordon Darcy matches the model most closely as he measures 5ft 11ins and weighs 14st 8lbs.