Taking up sports at a young age strengthens bones by up to 63 percent and reduces the risk of frailty in old age, researchers find.

As Andy Murray powers through the French Open it may not be the first thing on his mind, but he can be safe in the knowledge he will have strong bones in later life.

Children who play tennis and other sports when young can strengthen their bones by up to 63 per cent and reduce the risk of frailty in old age, a study has shown.

Researchers at Manchester Metropolitan University found that regular exercise when young has a far greater protective effect on bones than physical activity in adulthood.

They found that the bone in the racquet upper arm of young players was on average 40 per cent bigger than their non-racquet arm, and in some cases was up to 63 per cent larger.

Researchers worked with the Lawn Tennis Association to study players from 9 to 90 years old.

"The studies show that when you're older you are less able to get the benefits," said research leader Alex Ireland.

"Childhood therefore represents a good window of opportunity to really build strength for bones.

"Making (bones) stronger and bigger in childhood, especially in adolescence, means that you're less likely to have breaks when you get older.

"Having a fracture when you're older can be extremely detrimental to your life, you become less mobile and become weaker, reinforcing the importance of ensuing regular physical activity in youth."

Studies comparing sports people with less active people face criticism that bigger, stronger people tend to choose to play sport so differences found may not be a result of exercise.

In tennis players, both arms have the same nutritional and genetic influences, so researchers say they can be confident that physical activity is the cause of the large differences in bone strength.

Some small between-arm differences in bone strength are found in non-athletes, likely because people favour one arm when writing or carrying a bag, for example. However, the differences found in tennis players are about ten times greater than those in non-players.

In total, 51 male and 37 female players were analysed at the LTA Open Veterans Indoor Championships and the Open Veterans Clay Court Championship, and 30 male and 20 female juniors at the LTA British Junior Championships.

(China Daily 08/09/2014 page23)