Reliability of estimation of maximum performance capacity on the basis of submaximum ergometric stress tests in children 10–14 years old

Thirty-three 10-year-old boys repeatedly performed six symptom-limited, spiroergometric exercise tests according to the vita maxima method over an observation period of 4 years. Submaximum and maximum performance parameters were assessed and their correlation was calculated. The correlation of the heart rate at 1, 2 and 3 watts/kg body weight with the values of maximum performance capacity (wattmax and VO2max) and with the body-weight-related, relative maximum values was statistically significant. The correlation factors for the relative values were about twice as high (r=0.55) as the absolute values (r=0.27). The heart rate at 1, 2 and 3 watts/kg therefore was more characteristic of the relative values, which represent the state of training, and less for the absolute performance capacity, which depends to a great extent on body weight. However, the statistically significant correlation factors were too low to estimate reliably the state of training in an individual case. The correlation of physical working capacity at an HR of 170/min (PWC 170) with the maximum ergometric Watt performance was r=0.80 and therefore appears to be sufficient to estimate the maximum performance capacity in children. This is however only valid for children over the age of 11.