ADHD is one of the most common mental disorders found in children, and is characterised by impulsiveness, hyperactivity, such as not being able to sit still, and inattention or constant daydreaming.
There have been a few previous studies that compared ADHD and movement in both boys and girls.
In the study, researchers tested the movement abilities of 132 boys and girls with ADHD and 136 without the disorder. All the children were aged between seven and 15 years.
The children were tested for how fast and how well they could tap their toes, walk on their heels, maintain balance and keep a steady rhythm during a task compared to scores typical for their age.
It was discovered that girls with ADHD and the control group of children without ADHD were twice as likely to be able to control their movements for their age, quite unlike boys with ADHD, who showed continued difficulties.
"Our findings suggest that the differences between boys and girls with ADHD show up not only in behavior and symptoms but also in development of movement control, likely because girls' brains mature earlier than boys' brains," said study author E. Mark Mahone, PhD, with the Kennedy Krieger Institute and Johns Hopkins University School of Medicine in Baltimore, MD.
He added: "More studies related to ADHD and movement are needed that look at boys and girls separately and at younger ages," said Mahone.
The study is published in the latest issue of Neurology, the medical journal of the American Academy of Neurology.