University of Granada researchers, led by Enrique Garcia Artero, found the rate of teenagers with excessively low weight was 3.9 percent among boys and 4.8 percent among girls. In fact, the percentage among girls was higher than the 3.0 percent found for obesity.
Enrique Garcia Artero said the finding is important because it is easier to make lifestyle changes in teens than in adults.
"Firstly, because their personality, interests and habits are not still formed, so they are not as resistant to change as adults," the researchers said in a statement. "And secondly, because we have the best environment to model their habits: the educational system -- school and high school."
The researchers found tests easily implemented by a physical education teacher -- including the 40-meter race, hand grip strength, the long jump with feet together, body mass index, waist circumference and skin folds -- all easily conducted by the physical education teacher, to be valid and reliable assessments of aerobic capacity, muscle strength and body composition.
Study conclusions were based on 3,000 Spanish teenagers, 3,500 European teenagers and an additional sample of 126 teenagers from Granada.
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