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The papers published in this issue of Kinesiology Review are based on presentations delivered at the 2013 National Academy of Kinesiology meeting held in Colorado Springs, CO from September 19–21, 2013. The theme for the conference was Back to the Future: Refecting on the Past and Envisioning the Future for Kinesiology Research. The goals of the meeting were (a) to provide evidence-based impressions describing the key research discoveries/innovations in kinesiology over the last half century and (b) to project/predict key directions for research over the next 10–20 years.

In maintaining the strong multi-disciplinary spirit of the field of kinesiology, some of the presentations were specific to our sub-disciplines and other presentations were related to physical activity and movement in different populations. The presentations were designed to catalyze discussions about where we came from, how kinesiology has matured, and where we anticipate new knowledge and discovery will take us in the future.

Part 1 reviews the literature concerning peak blood lactate responses to exercise in children. After a brief overview of lactate metabolism, an analysis is presented comparing children to adults regarding peak blood lactate concentration. Possible factors accounting for lower blood lactate concentrations during maximal exercise in children are considered.

Part 2 reviews the literature concerning the lactate threshold in children. An analysis is presented comparing children to adults regarding responses to submaximal exercise, and the lactate threshold as a percentage of VO₂max. Possible explanations for lower blood lactate concentrations during submaximal exercise in children are considered.

Precise quantification of physical activity is necessary in order to evaluate the relationship between physical activity and various types of disease and/or risk factors associated with disease. With the emergence of the study of the origins of coronary heart disease risk factors in children, it is imperative that accurate measurement of physical activity in the pediatric population be obtained. This review critically evaluates various field measures of physical activity in children including motion sensors, questionnaires, and heart rate. A new heart-rate quantification procedure is also presented that may provide an index of the quality of physical activity.

In this study, running economy differences between boys and men at a common speed (ABS = 9.6 kph) and at a relative speed adjusted for body size (REL = 3.71 leg lengths per second) were examined. The caloric cost relative to mass was significantly higher for the boys for ABS (men = .17, boys = .20), but not for REL (both .19). The relative heart rate (%HRmax) and ventilatory equivalent were higher for the boys at ABS, but not at REL. Boys had significantly higher stride frequencies in both conditions. Stride length/leg length was greater for boys during ABS, and for men during REL. Respiratory exchange ratios (RERs) were not different at ABS (men = .94, boys = .96), but during REL, boys had a significantly lower RER (.93 vs. .98). Running economy differences between adults and children are reduced when speeds are adjusted relative to body size. This model may be useful for identifying developmentally based differences in the physiology and biomechanics associated with exercise.