HEALTH conscious Singaporeans who take part in weekend sports and other physical activities would do well to heed the advice of a sports medicine expert: Don't try to achieve too much too soon.

Those in a hurry to see progress in their activity - to lift heavier weights, run longer distances or swim extra laps - sometimes end up injured.

Dr Kelvin Chew, consultant sports physician with the Sports Medicine Centre and the Changi Sports Medicine Centre under the Singapore Medical Group, says a large proportion of injuries are due to overuse of muscles.

"So listen to your body as most injuries give some sort of warning before they get worse," he advises.

"It is important to bear in mind if you train and play hard that you should also pay attention to recovery and rest to allow the body to repair itself."

Dr Chew says acute injuries are the result of accidents in which a large force is applied to the body over a short period of time, thus causing the injury.

Overuse injuries occur over time with repetitive microtrauma culminating in injury.

"Injuries in sports like swimming, running, cycling and kayaking generally result from overuse," he says.

Internal and external factors are involved in such injuries.

Internal factors include the body's anatomic imbalances, such as weak muscles, inflexibility, or foot abnormalities like flat foot.

Says Dr Chew: "These factors can be easily addressed by regular strengthening, stretching exercises and the use of appropriate equipment."

The external factors include the training programme and the environment.

"Trying to increase the volume and intensity of exercise too soon can lead to problems," he says.

"In general, we should not exceed more than 10 per cent increments in volume and intensity per week.

"The terrain and exercise surface can also contribute to injuries. For example, cement surfaces are hard and therefore lack cushioning for the feet and skeleton. Potholes, of course, can also contribute to sprains and accidents."

He advises all who do physical exercises to seek professional advice on proper techniques.

Dr Chew says that fitness conscious senior citizens should undergo medical evaluation to identify any medical condition that may limit their ability to exercise or may increase the risks involved in exercise.

He says physiological changes common in the seniors include decreased muscle mass and strength, aerobic endurance and flexibility.

He adds: "But most of these changes may be attributed to decreased activity. Thus, regular exercise to maintain strength, flexibility and endurance is important."

Prevent injury during exercise by knowing proper techniques for weight-lifting, like steady controlled lifts and prevention of joint hyperextensions.

"It is always wise to train with a spotter. The training programme involving the number of exercises, repetitions and weight increases should be well-designed and rational." He reminds everyone to have fluids at regular intervals to rehydrate after training. A decent gauge of fluid status, he adds, is weight loss after training.

Those participating in endurance activities lasting more than 60 minutes could do well with isotonic drinks.

"After exercise, a light easily digestible carbohydrate-rich snack can help," says Dr Chew.

As for the young, he says that sports participation promotes physical maturity and helps build self-esteem.

"The programmes should be as inclusive as possible for all children. For example, no child should be left on the bench in the team. Every child should play at least half of every game."