This systematic review aims to analyze the validity (invasive and noninvasive protocols) of aerobic endurance evaluation methods established in the late 20th century and their practical application in creating training series in different sports events. The PRISMA system was used for systematic review. It was identified that high number of studies support the concept of the evaluation of aerobic endurance, i.e., aerobic threshold (AnT), in terms of its significance for the determination of training series and training intensity aimed at aerobic endurance improvement. During the protocol of testing and construction of the lactate curve (La – work capacity), the method based on sampling and measurement of lactate concentration in blood is given priority as a more valid instrument for AnT determination than the method based on ventilatory parameters and heart frequency. Authors note that the parameters based on which AnT is determined are expressed in different units of measure (m/min, km/h, ml/kg/min) so that AnT, as such, does not only represent the measure of aerobic endurance but also the measure of maximal oxygen consumption (VO2max) and mechanical efficiency. The results of the study indicate that terms related to AnT should be removed from official use. More precisely, researchers and coaches focus on a method related to the interpretation of the lactate curve (at a certain %VO2max) to determine whether there has been an improvement (or not) in aerobic endurance based on its displacement (to the right or to the left).

The aim of this study was to examine the relationship between morphological
characteristics and motor abilities of boys and girls aged from 11 to 14 so that the process of
physical education could be in line with the dynamics of growth and development as well as
the differences between the sexes. The total sample consisted of 730 subjects, divided into
four age groups of 11, 12, 13 and 14. Eight motor tests were conducted and 9 anthropometric
measures were taken. The boys of all ages achieved better results in tests of coordination, repetitive and explosive power, while girls of all age groups scored better in flexibility tests. The largest differences between the sexes at the ages of 11 and 12 years were the results of
variables evaluating motor abilities. At the age of 13, a significant difference in skinfold
thickness was found in favor of girls and at the age of 14 in the voluminousness in favor of
boys. In boys aged from 13 and 14, the increase in body volume was negatively correlated
with the increase in skinfold thickness, indicating that the increase of voluminousness is
caused by the increase of muscle mass. It is therefore concluded that the linear increase of the
differences in motor performance tests under 14 years of age is caused by increased muscle
mass in boys, especially in tests where achievement depends on the strength and production
of force.