Some Irish teenagers are already showing signs of early onset heart disease as a result of their poor fitness levels, new research has found.

Heart disease is currently Ireland's biggest killer and it involves the build-up of plaque in the walls of a person's blood vessels.

According to this latest research, 15 and 16-year-old boys with low levels of fitness had much more plaque in the walls of the arteries responsible for supplying blood to the brain, compared to boys with high levels of fitness.

"The research clearly shows the danger of poor levels of aerobic fitness with 15-year-olds already showing signs of early onset heart disease. A high level of fitness reduces the risk for major chronic diseases such as cardiovascular disease, cancer, depression and diabetes," commented Prof Niall Moyna of the Centre for Preventive Medicine in Dublin City University (DCU).

The research was released to coincide with the launch of Aviva Health's Schools' Fitness Challenge - a six-week challenge which aims to improve young people's cardiovascular health.

"The challenge aims to provide teenagers with a measure of their cardiovascular fitness and increase their awareness of how important physical activity is to their overall health. This simple six-week challenge has been designed to improve cardiovascular health by motivating children to prioritise their aerobic fitness," said exercise physiologist and challenge monitor, Dr Sarah Kelly.

One method of assessing fitness during the challenge is via the bleep test, also known as the shuttle run. This involves participants continually running between two lines that are 20 metres apart in time to recorded bleeps.

The running speed is increased at one minute intervals and the participant must attempt to run between the lines as many times as possible in time with the bleeps. This can provide valuable information about the fitness of an individual.

According to the new research, boys with low fitness levels who performed poorly in this test were more likely to be overweight, have higher blood pressure and higher cholesterol compared to those with moderate or high fitness levels.

Last year's Schools' Fitness Challenge saw over 13,000 students from 26 counties taking part. The most improved school recorded a 68% improvement in fitness levels over the six-week period.

This year's challenge is open to first, second third and transition year pupils. Schools interested in taking part must register here by Saturday, January 17. There are nine different prize categories, including Ireland's fittest girls' school, boys' school and mixed school, and most improved school overall. Each winning school will receive €500 worth of sports equipment.

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