Researchers studied 8,000 children and measured their fitness, muscle strength and power and found that those born in the autumn had a clear physical advantage over children born at other times of the year.
“We already know that children born at the beginning of the school year in September have an academic advantage, are more likely to get picked for school teams and are even more likely to go on and play professional sport,” explains Dr Gavin Sandercock, who led the research. “This is what is called ‘the relative age effect’. Our research however, suggests something else may be at work.
“We controlled for the relative age effect in this study so we are only comparing month by month. What we found was quite surprising, that a boy born in November can run at least 10% faster, jump 12% higher and is 15% more powerful than a child of exactly the same age born in April. This is, potentially a huge physical advantage.”
The researchers suggested that higher Vitamin D levels from exposure to sunlight late on in pregnancy could be the cause.
“We know autumn babies tend to be bigger than spring-born children,” adds Dr Sandercock. “But this is the first time anyone has found this might lead to being fitter.
“The major problem for children born in the spring and summer is that as well as being relatively younger than children in their school-year born in autumn, it also seems they have a real physiological disadvantage too.”
This problem could have a real effect on spring and summer-born children’s sporting chances. The researchers suggest that using ‘age on day of event’ groupings would help to reduce this bias and that some sports would be fairer if children were grouped by weight.