Researchers say kids can build bone strength by simple exercise — Bouncing at the bell. The WE News Archives

Bounce at the Bell

Researchers: Kids Can Build Bone Strength by Simple Exercise

By John McKenzie
Dec 9 2003

The General Brock School in Vancouver looks like any other elementary school. Until the bell sounds.

About 30 sixth-graders then stand beside their desks and begin to jump. Not for long. Just a few seconds. But scientists now say that can be enough to build stronger bones.

Karen Chalmers, the principal, was skeptical at first.

"Initially my first reaction was, 'Oh, come on. That little bit of time will make that big a difference?' " said Chalmers. "But they gave us the statistics and research, and the research says it makes a difference."

Stronger Bones Could Prevent Osteoporosis Later

Professor Heather McKay at the nearby University of British Columbia had conducted a pilot study that followed almost 100 students. The children had similar eating habits and physical activity levels. The only difference was that half of them jumped at the bell (just five jumps, three times a day) and half of them did not jump.

McKay used X-rays to measure the bone mass of each child at the start of the study and again eight months later. She found that those who had jumped actually built 3.2 percent more bone mass in the hip region of the body than the other children. That could be enough to postpone, or perhaps event prevent, osteoporosis later in life.

"We're talking about these children gaining in eight months what we would see women lose in three years around menopause," McKay told ABCNEWS.

Research has shown that while running is good for the cardiovascular system, jumping or high-impact exercise is best for building bone.

When a child runs, for example, every time his foot hits the ground, the skeleton absorbs a force of about twice the youngster's body weight. But jumping exerts a much greater force, about five times the child's body weight.

That causes the bone to bend ever so slightly, and triggers the bone's building cells to turn on.

"The key is that there is a higher-than-usual impact applied to your bones," said McKay.

It's also crucial that the impact occur regularly during childhood, the critical period for bone development. Twenty-six percent of all the bone you will ever develop is formed during puberty: 10 to12 years of age for girls, 12 to 14 years of age for boys.

Today, the "Bounce at the Bell" program has been introduced in six Vancouver schools.

"It takes no money to run the program," said McKay. "It takes no special training, and we're talking about an investment of about a minute and a half a day."

It also provides some unintended benefits. Ernest Wong, a sixth-grade teacher at the school, said: "For the hyper kids, it tends to calm them down, and for the kids who perhaps didn't get enough sleep, it tends to pick them up with some energy."

British: Antidepressants Unsuitable for Children
THE ASSOCIATED PRESS
December 12, 2003

London — Most varieties of a common class of antidepressants are not suitable for children, Britain's drug regulator says.

The Medicines and Healthcare Products Regulatory Agency issued a statement Wednesday saying it had reviewed scientific studies and concluded there was no solid evidence that the benefits outweigh the possible side effects for patients under 18.

The drugs, known as selective serotonin reuptake inhibitors, or SSRIs, have never been licensed for use in children in Britain.   In the United States, the only antidepressant specifically approved for use in children is Prozac, but doctors can prescribe approved medicines for any condition.

Nearly all the research on the pills was done on adults.   Although the drugs are not licensed for children, it is known that some doctors prescribe them anyway, said Gordon Duff, chairman of the independent advisory Committee on Safety of Medicines.

"This gives parents, young people and those who treat these devastating illnesses the information they need to make informed decisions about treatment," Duff said.

The panel said that only Prozac, or fluoxetine, has enough research on children to indicate the benefits outweigh the side effects, which can include suicidal feelings, anxiety, insomnia, weight loss and headaches.

The Department of Health estimates that 30,000 to 40,000 children and teenagers are prescribed SSRIs in the United Kingdom and that about half of them are treated with Prozac.

The advisory panel was set up in May to look into the effects on children of paroxetine, marketed in Europe as Seroxat and in the United States as Paxil.   In October, the U.S. Food and Drug Administration issued a more general health advisory alerting physicians to a possible link between antidepressant drugs and suicidal feelings in the young.