摘要:T wenty two years ago, Armstrong (1989) reported that "Children are fit, but not active!" He described the physical activity (PA) level of over 300 British youths aged 11 to 15 years old, as measured by heart rate monitors. Armstrong reported that 50% of the girls and more than 25% of the boys did not perform any 10 minutes bout of PA at a heart rate ≥ 139 beats per minute (bpm). In addition, physical fitness (PF) was assessed with a treadmill VO 2 max test. The participants were as fit as the first children that were tested in laboratory settings 50 years before.