Very premature children show low fitness levels

Last Updated: 2008-08-15 16:01:42 -0400 (Reuters Health)

NEW YORK (Reuters Health) - School-age children who were born very prematurely may be considerably less physically fit than their peers, a new study suggests.

Australian researchers found that children who were born before the 32nd week of pregnancy had only about half the exercise capacity of children who were born at term. This was despite the fact that their lung function was nearly as good.

Given the similarity in lung health, the difference in fitness is "striking," the investigators report in the journal Pediatrics.

Studies are now needed to weed out the cause of the lower fitness levels -- and to see whether exercise training can help, according to the researchers, led by Dr. Lucia Jane Smith from Children's Hospital at Westmead, in Sydney.

Smith and her colleagues assessed the lung function and fitness levels of 126 children who were born before the 32nd week of pregnancy, and that of 34 children who were born full-term. The children were 10 years old, on average.

The researchers tested the children's exercise capacity with a 6-minute walk and a "shuttle run" where the children had to run from one marker to the next, each 20 meters away.

During the shuttle run, Smith's team found, the preterm group generally ran out of steam far sooner than the full-term group did.

The researchers say the findings demonstrate significant impairment in exercise capacity in children born very preterm, despite evidence of only mild differences in their lung function.

The relatively poor fitness, they point out, seems to be "out of proportion to the degree of airflow limitation."

Why this is so, and whether it can be improved with physical training, requires further study, the researchers write.

SOURCE: Pediatrics, August 2008.

http://www.reutershealth.com/archive/2008/08/15/eline/links/20080815elin028.html