The Astrand-Ryhming Nomogram as a Predictor of Aerobic Capacity for Secondary School Students

Book excerpt: The purpose of the study was to investigate the validity of the Astrand-Ryhming nomogram for males and females of secondary school age by comparing values obtained from the Astrand-Ryhming "predicted" maximal oxygen intake test with those of the Astrand "actual" maximal oxygen intake test*, The secondary purposes were to determine regression lines between the actual and predicted values, to investigate sex differences with respect to work capacity, to compare the work capacity of Alberta secondary school students with that of Europeans and Americans of a similar age, and to investigate the work capacity changes during the summer vacation,. The study was composed of two separate investigations designated as Experiments I and II. In Experiment I maximal oxygen consumption was measured by both the Astrand-Ryhming predicted and the Astrand actual methods for 29 males and 27 females of secondary school age, In Experiment II the maximal oxygen consumption of $00 males and 4^7 females who were considered to be representative of the secondary school population of Alberta was measured by the Astrand-Ryhming predicted maximal oxygen intake test. The difference between the actual and predicted maximal oxygen consumption values in Experiment I were analyzed under three conditions for each sex, i 0 e 0 , the predicted values were taken from (I) a separate submaximal test,(II) the first work level of the actual test and (III) the second of the two tests Within the limitations of the study the following conclusions were made. The Astrand-Ryhming nomogram predicted mean maximal oxygen consumption values equivalent to those obtained on the Astrand actual test for females of secondary school age. The predicted test underestimated the male values. The correction factor should be employed with this age group. The Astrand-Ryhming predicted test appears to differentiate between individuals who are in widely different states of training but not between individuals who are in approximately the same state of training. The mean aerobic capacity of males is superior to that of females for all age groups. Alberta students may have inferior work capacities as compared to Swedish children of the same age but Alberta children compare favourably with children of other areas of the same age. The aerobic capacity of females decreases significantly over the summer vacation while that of males shows no change. There is a need to study in detail, the variables which affect the predicted maximal oxygen intake value.