Physiological responses of elite Laser sailors to 30 minutes of simulated upwind sailing

In this study, we tested the hypothesis that elite dinghy sailing is a whole-body, dynamic, repeated-effort sport, and that increased heart rate and oxygen consumption reflect its dynamic element. Six elite male Laser sailors (mean age 19.7 years, s = 1.82; height 1.81 m, s = 0.03; body mass 78.0 kg, s = 4.1) performed a cycle ergometer test to volitional exhaustion to determine peak oxygen uptake (VO(2peak)) and a simulated 30-min upwind leg sail on a specially constructed Laser sailing ergometer. The simulation protocol was based on video analysis of previous Laser World Championships. Expired gases were collected in Douglas bags, heart rate recorded at rest and after every 5 min, and pre- and post-simulation capillary blood samples taken for blood lactate analysis. Results were analysed with a one-way analysis of variance. Mean VO(2peak) was 4.32 l . min(-1) (s = 0.16). Mean simulation VO(2) was 2.51 l . min(-1) (s = 0.24) and peaked at 2.58 l . min(-1) (s = 0.25) during the 5th minute. Mean simulation heart rate was 156 beats . min(-1) (s = 8), peaking during the final minute at 160 beats . min(-1) (s = 10). These results suggest that, unlike pseudo-isometric static hiking, elite dinghy sailing demands a substantial proportion (58%VO(2peak), s = 5.6) of aerobic capacity.     

Relationship between toy and material use and the occurrence of social interactive behaviors by normally developing preschool children

The purpose of this naturalistic study was to identify the kinds of social behaviors that normally developing preschool children exhibit while manipulating various toys and materials found in most preschool settings. One hundred fifteen 3-, 4-, and 5-year-olds in four day-care centers were observed during free play periods. Thirty-eight available toys and play materials were rated as to whether they were used in an Isolate, Parallel, Sharing/Cooperative, or Physical Assistance context. The resulting data on toy/material use are discussed in terms of selecting physical stimuli in social behavior modification efforts that clearly set the occasion for positive social interaction.     

The activity context of preschool children's social interactions: A comparison of high and low social interactors

The purpose of this observational study of the activity context in which preschool children engaged in positive social interactions was to produce a data source that could be used to assist in the identification of socially withdrawn children, and to select efficient training contexts in which to develop the social behavior repertoire of withdrawn youngsters. Eleven high-rate and 10 low-rate social interactors, ranging in age from 36 to 72 months, were observed for 12 10-minute sessions across a 3-month period. Six activity contexts were coded by trained observers: Observer, Isolate, Parallel, Game, Cooperative, and Fantasy. The results indicated that: (a) Low-rate children engaged in significantly more Isolate and Observer activity than did high-rate children. (b) High-rate children engaged in significantly more Cooperative and Fantasy activity than did low-rate children. (c) There were no significant differences between groups for Game and Parallel activities. Results are discussed in terms of the concurrent validity between frequency of interaction measures and the activity context data, the developmental progression of social skills acquisition, and the selection of treatment contexts for withdrawn children.     

Abilities and skill acquisition: A latent growth curve approach

The relationship between abilities and skill acquisition has been the subject of numerous controversies in psychology. However, while most researchers implicitly or explicitly accept the idea that abilities and skill acquisition should be related, empirical research has failed to provide evidence for a consistently strong correlation between the two constructs. Based on the reanalysis of a study on skill acquisition using the air traffic controller task TRACON [Ackerman, P. L., Kanfer, R., and Goff, M. (1995). Cognitive and Noncognitive Determinants and Consequences of Complex Skill Acquisition. Journal of Experimental Psychology. Applied, 1(4), 270–304], it will be shown how latent growth curve modeling can help to gain a better understanding of the relationship between human abilities and skill acquisition. A brief introduction into the basic concepts of latent growth curve modeling will be given, particularly with regard to the advantages for the analysis of skill acquisition and its determinants. The goal is thereby to provide evidence for a much closer association than commonly assumed and to offer a new, differential, perspective formerly obscured by traditional between-subject analyses.