The relationship between physical activity,fitness, physical complaints and BMI in German adults – results of a longitudinal study

Objectives: This study’s aims were to describe the development of physical activity, physical fitness (PF), subjective (physical complaints (PC)) and objective (Body mass index (BMI)) health measures and to examine the relationship between the development trajectories. In addition, the study also aimed to assess the influence of sociodemographic determinants (age, sex, socioeconomic status (SES)) in German adults over a period of 18 years. Methods: The longitudinal study population comprises of 721 men and women, aged 33–76 years over the study period. There was self-report of physical activity and PC and testing of physical fitness and BMI in each study year (1992, 1997, 2002 and 2010). Latent growth curve models were used to analyse the development. Results: Physical activity slightly increased while fitness, PC and BMI worsened over the course of 18 years. Sex, age and SES play important roles concerning physical activity, fitness and health. Several integrative associations could be detected between physical activity, fitness, PC and BMI as well as their trajectories. In particular, high initial levels of physical activity and fitness protect from high PC and BMI.The slope of physical activity was not significantly associated with slopes of fitness, PC and BMI. However, increase of fitness resulted in decrease of PC. Conclusions: A general positive development regarding the amount of physical activity could be detected. However, if it is only an unsystematic increase of physical activity, this is not in itself enough to achieve health benefits. The strengthening of fitness should be focused when increasing physical activity, since only then a health benefit is possible.     

Variation and homogeneity in affective responses to physical activity of varying intensities: An alternative perspective on dose – response based on evolutionary considerations

A model for systematic changes in patterns of inter-individual variation in affective responses to physical activity of varying intensities is presented, as a conceptual alternative to the search for a global dose?–?response curve. It is theorized that trends towards universality will emerge in response to activities that are either generally adaptive, such as moderate walking, or generally maladaptive, such as strenuous running that requires anaerobic metabolism and precludes the maintenance of a physiological steady state. At the former intensity the dominant response will be pleasure, whereas at the latter intensity the dominant response will be displeasure. In contrast, affective responses will be highly variable, involving pleasure or displeasure, when the intensity of physical activity approximates the transition from aerobic to anaerobic metabolism, since activity performed at this intensity entails a trade-off between benefits and risks. Preliminary evidence in support of this model is presented, based on a reanalysis of data from a series of studies.     

Weekday–weekend variations in mother-/father–child physical activity and screen time relationship: A cross-sectional study in a random sample of Czech families with 5- to 12-year-old children

This study assessed the associations between these factors in a random sample of Czech families with preschool and school-aged children. A nationally representative sample comprised 185 families with preschool children and 649 families with school-aged children (dyads; both parents and child n?=?365, mother and child n?=?730, and father and child n?=?469). The participants wore Yamax Digiwalker SW-200 pedometers at least four weekdays and both weekend days and completed family logbooks (anthropometric parameters, daily step counts (SC), and screen time (ST)). When a parent (fathers at weekends and mothers both on weekdays and at weekends) achieved 10,000 SC per day, their children were also significantly (OR?=?2.93–6.06, 95% CI?=?2.02–9.26) more likely to meet the daily SC recommendation. On the contrary, the involvement of fathers in organized leisure-time PA reduced their children's odds of meeting the SC recommendation on weekdays (OR?=?0.53, 95% CI?=?0.31–0.89) and at weekends (OR?=?0.41, 95% CI?=?0.24–0.72). The excessive ST of parents at weekends reduced the odds of their children meeting the SC recommendation (mother–child dyads: OR?=?0.44, 95% CI?=?0.26–0.72; father–child dyads: OR?=?0.63, 95% CI?=?0.37–1.06). High levels of parents’ PA contribute to the achievement of the recommended daily PA in children on weekdays and at weekends. Excessive weekend ST of parents reduces their odds of their children achieving the recommended daily PA; however, the influence of parents’ PA on their children’s achieving the recommended daily PA is stronger than the inhibitory effect of ST.     

A dolphin only looks like a fish: Players’ behaviour analysis is not enough for game understanding in the light of the systems approach – a response to the reply by McGarry and Franks

Abstract

In this article I defend my previously published system approach to game playing in sports (Lebed, 2006). Founded on the main argument of mine about insufficiency of performance analysis only for games study, it is based on an inter-disciplinary comprehension of sporting game events from four different angles: the logical-philosophical, the behavioural (performance), the anthropological, and complexity angles. The paper consists of four parts, corresponding to the four angles. The first three parts offer deconstructive and reconstructive analysis. The three provide criticism of McGarry and Frank's arguments against my view of complex dynamical systems in sports. The logical analysis negates my opponents’ general view of a match (a process) as a dynamical system. The behaviour analysis refutes their claim about couple oscillator dynamics as a universal dynamically interpreted model of game playing. The anthropological panoramic vision of sporting games leads me to conclude that my opponents’ analysis of two exclusively interacting sides in a squash or soccer contest is too narrow and insufficient to explain the broad diversity of games. According to the, classification suggested in Lebed (2004), I offer seven possible models that can systematically reflect different groups of games. In the fourth part, the complexity angle is analysed from a constructive point of view. Here I take one of the above seven models and try to outline a ‘‘soccer-like’’ game perspective modelling founded on the view of play process as a conflict of two four-level self-regulating complex systems, where each one is additionally involved in its own loop of cybernetic regulation.