Perceived variety,psychological needs satisfaction and exercise-related well-being

Objective: Perceived variety represents a psychosocial experience that gives rise to, and supports the maintenance of, an individual’s well-being. In this study, we developed an instrument to measure perceived variety in exercise (PVE), and examined whether ratings of PVE predict unique variance in indices of exercise-related well-being in addition to that explained by satisfaction of the three basic psychological needs (for competence, relatedness and autonomy) embedded within self-determination theory (SDT). We also examined the extent to which variance in perceived variety is empirically distinct from (or subsumed by) competence, relatedness and autonomy in the context of exercise.

Methods: A convenience sample of community adults (N?=?507) completed online surveys twice over a six-week period (n?=?367).

Results: PVE was found to prospectively predict unique variance in indices of exercise-related well-being, in addition to that explained by perceived competence, relatedness and autonomy. Using exploratory and confirmatory factor analytic procedures, perceived variety was found to be empirically distinct from perceived competence, relatedness and autonomy.

Conclusion: Results from this work suggest that perceived variety holds potential for theoretical and applied advancements in understanding and predicting well-being in exercise settings.     

Haptic and visual influences on grasp point selection

When using precision grip to pick up objects, there are many possible pairs of grasp points that permit the thumb and index finger to exert opposed forces for secure grip. Previously, it was shown that individuals select grasp points so that the line between them (grasp axis) passes through or near the center of mass (CoM), thus minimizing the torque around the grasp axis during lifting. The accuracy of grasp axis selection depended on object spatial symmetry, indicating the importance of vision. The authors investigated how grasp point selection is influenced by haptic as well as visual information. Ten participants lifted cuboids whose CoM was located either symmetrically in the geometric center or asymmetrically toward one end. Results for the asymmetric cuboid revealed that grasp points migrated toward the asymmetric CoM from the geometric center. This was more pronounced in the presence of visual cues that reliably indicated the location of CoM. The results suggest that grasp point selection is influenced by a multimodal representation of CoM.