It can lead youngsters into a sport not of their choice, create an intensity that takes away the fun, compromise their athletic development, make them vulnerable to injury, and lead to psychological pressure that can result in burnout.
The dangers of early specialisation have been highlighted by a number of studies, including a consensus statement published in the British Journal of Sports Medicine on reducing risk of burnout and injury in youth sport, which emphasised the benefits of diverse sports training during early to middle adolescence.
These findings have been supported by analysis of Team GB at the 2012 Olympic Games in London, which showed the majority of the high performing athletes – including those who medalled – had come into their sports late, at 16-plus or even later.
David Faulkner, coaching at Millfield
It is widely accepted that there are sports which suit later specialisation, such as rowing, athletics, cricket and now, with recent work by the RFU, rugby.
Sports organisations are increasingly recognising the value of gaining wider skills to improve tactical, technical mental and physical development, and to provide an edge over competitors.
Furthermore, there is growing recognition that coaches have often been falling into the trap of focusing upon young people who appear talented at around the ages of 10 to 13, while ignoring other potentially talented youngsters.
It was with all this in mind that we established the Millfield Institute of Sport and Wellbeing, to formalise what we have already been doing informally to ensure all pupils engage in athletic development, enjoy a variety of sports and provide opportunities to transfer to sports they may have never considered.
The aim is to support every individual to leave Millfield with a holistic toolbox, so that when they progress to university or professional sport they have all they need in terms of technical, physical and mental abilities, together with a wider holistic understanding in areas such as teamwork, leadership, and dealing with setbacks.
By playing a range of sports before deciding upon a specialism, young people achieve a level of athletic development that enables them to deal with higher training levels and to perform more effectively.
This is because they are using their bodies more effectively than they would by focusing upon just one sport, which would result in their motor skills – how they operate – becoming one dimensional, and causing them to hit a physical ceiling.
There is also the issue of injuries – usually hamstring, groin and shoulder – as a result of overplaying the developing body.
Also worth bearing in mind is the valuable social experience gained by pupils involved in a range of sports, either as part of a team or in individual events.
The benefits of good coaching are not solely defined by results achieved at school. The true test will be how pupils are performing in their chosen sports and careers a decade after leaving.
David Faulkner, director of sport at Millfield, and gold medal winner for Team GB Hockey at the 1988 Olympics
7:00AM BST 21 Apr 2015