Personal Trainers Forum

[Personaltrainer]

Personal Hydration Strategy

Professor Ron Maughan of Loughborough University reports on a good example of the use of science in the service of football and the individuals who play it.

Hydration is perhaps a more emotive issue in American football where fatalities have occurred in training and competition, but at a more mundane level, 'there is good evidence that players who become dehydrated are more susceptible to the negative effects of fatigue, including loss of performance and increased risk of injury. There is also growing evidence that excessive sweat losses, especially high salt losses, can be a factor in some of the muscle cramps that affect players in training and competition.'

Maughan and his team tested players at a number of top European clubs and produced results that were consistent between clubs when training is similar, but the variability between individual players is striking.

Key findings based on a typical 90-minute training session:

1. Average sweat loss is typically two litres, but the range is wide – from 1L to as much as 3L.

2. Average fluid intake is 800-1,000ml – but again the range is wide (250ml to more than 2L).

3. There is no relationship between the amount of sweat a player loses and the amount he drinks.

4. Sweat salt content varies greatly between players.

These findings may appear simplistic and predictable says Maughan, 'but they give the training staff of a club which is serious about maximising its human assets a chance to prescribe fluid according to the player's needs. The aim should be not to drink too much, as some players do, but to drink enough to limit weight loss to no more than 1-2% of the pre-exercise weight.'