A CROSS-SECTIONAL AND LONGITUDINAL INVESTIGATION OF A PHYSICAL ACTIVITY CLASSIFICATION SYSTEM

The objective of this dissertation was to determine the validity of a proposed system of activity classification and the responses to training in each of its categories. Six studies were conducted. A cross-sectional investigation using well-trained athletes determined if they could be differentiated by their abilities in each activity category. Five training studies using untrained subjects examined the responses to training in each of the proposed categories: anaerobic power (ANP), anaerobic capacity (ANC), lactate tolerance (LTOL), high-intensity aerobic (HAER), and low-intensity aerobic (LAER).;The five training studies showed that carryover effects can result from training in one category that enhance the abilities in other classes. ANP training improved ANP, ANC, and VO;Training in the anaerobic categories (ANP, ANC, and LTOL) has a general training effect in that subjects improved their anaerobic and aerobic abilities. These adaptations are probably due to the high intensity of the training. The adaptations to aerobic training (HAER and LAER) were more specific, as VO;Based on the cross-sectional and training studies, the proposed system should be modified to the following four categories: phosphagen utilization, anaerobic and aerobic glycolysis, aerobic glycolysis, and aerobic lipolysis.;In the cross-sectional study, powerlifters (PW), gymnasts (GY), wrestlers (WR), 10 km runners (TK), and ultramarathoners (UM) were selected as representing well-trained athletes who compete in separate activity categories. The athletes were tested and their abilities were compared in each of the five classes. The proposed system separated the athletes with high anaerobic and low aerobic ability (PW) and vice versa (TK, UM), but not those with high abilities of both (GY, WR). This suggested that ANC and LTOL did not distinguish different types of activity, and that some athletes are distinguished by possessing high levels of both anaerobic and aerobic ability.