Factorial and convergent validity of the Exercise Identity Scale in a German adult sample

The purpose of the present study was to examine the factorial and convergent validity of the German translation of the Exercise Identity Scale (EIS; Anderson & Cychosz, 1994). We introduce a bifactor model as a possible alternative to the previously discussed one- and two-factor models. Using an online study with 530 participants, our results suggest that the EIS should be considered a unidimensional measure. For this one-factor model, temporal invariance (time interval: 2 weeks) and invariance between men and women could be established. Relations to similar constructs were in the expected directions. We provide a psychometrically sound German version of the EIS, which demonstrated factorial and convergent validity in this study. The use of the scale in German samples is likely to advance research on exercise adoption and maintenance by integrating the exercise identity construct.     

Preferences for Explanation Generality Develop Early in Biology But Not Physics

One of the core functions of explanation is to support prediction and generalization. However, some explanations license a broader range of predictions than others. For instance, an explanation about biology could be presented as applying to a specific case (e.g., “this bear”) or more generally across “all animals.” The current study investigated how 5‐ to 7‐year‐olds (N = 36), 11‐ to 13‐year‐olds (N = 34), and adults (N = 79) evaluate explanations at varying levels of generality in biology and physics. Findings revealed that even the youngest children preferred general explanations in biology. However, only older children and adults preferred explanation generality in physics. Findings are discussed in light of differences in our intuitions about biological and physical principles.     

Retroactive interference effects of mentally imagined movement speed

In two retroactive interference experiments, we assessed the effect of mentally imagined movement speed on subsequent motor performance. All participants performed a sequential motor action at three speeds during a baseline test and a retention test. During the retention interval of Experiment 1, the participants (n = 50) physically performed the action at a slow speed, physically performed it at a fast speed, imagined it at a slow speed, imagined it at a fast speed, or performed a no-practice control task. In Experiment 2, the participants (n = 24) imagined the movement, overtly vocalized words, or both, all at a slow speed. The results revealed that the speed of the imagined motor action affected the speed of subsequent performance in the retention test and that imagery and physical practice were functionally equivalent. The results are consistent with Lang's bio-informational theory.     

Fluid ingestion and exercise hyperthermia: Implications for performance,thermoregulation, metabolism and the development of fatigue

The development of fatigue during exercise and the subsequent onset of exhaustion occur earlier in the heat than in cooler environments. The underlying mechanisms responsible for the premature development of fatigue in the heat have yet to be clearly identified. However, the proposed mechanisms include metabolic, cardiovascular and central nervous system perturbations, together with an elevated core temperature. Fluid ingestion is one of three strategies that have been shown to be successful in enhancing the performance of endurance exercise in the heat, with the other interventions being precooling and acclimatization. However, like the development of fatigue in the heat, the mechanisms by which fluid ingestion allows for improved exercise performance remain unclear. We propose that fluid ingestion enhances exercise performance in the heat by increasing the heat storage capacity of the body. We suggest that the thermoregulatory, metabolic and cardiovascular alterations that occur as a result of this increased heat storage capacity contribute to performance enhancement when fluid is ingested during exercise heat stress.     

Changes in the perception of action possibilities while climbing to fatigue on a climbing wall

Abstract

In two experiments we examined changes in the perception of action possibilities as a function of exertion. In Experiment 1, participants repeatedly climbed on a climbing wall in a series of trials that progressively increased in number to 10 trials, resulting in increased exertion. Before and during climbing, the participants judged their maximum reaching height and perceived exertion. On a separate day, participants climbed another 10 trials while performing actual maximum reaches. Higher perceived exertion was associated with decreases in perceived maximum reach while the actual reaches did not decrease. However, the perceptual changes occurred early during task execution when the participants were not yet fatigued. When exertion set in, neither perceived nor actual maximum reaching appeared to be affected. In Experiment 2, we included exhaustion trials. The findings replicated the early changes in perception observed in Experiment 1, which may be explained by hands-on experience with the task. Furthermore, while climbing to exhaustion, perceptual judgements largely changed in keeping with changes in the actual maximum reach. Thus, there appeared to be a functional relationship between participants' actual action capabilities, rather than their state of physical fatigue per se, and perceived action possibilities.     

Differences in the Intensity and Duration of Adolescents' Sports and Exercise Across Physical and Social Environments

We used data from the American Time Use Survey (years 2003–06) to analyze whether the intensity and duration of high school students' (ages 15–18 years) sports and exercise bouts differed across physical and social environments. Boys' sports and exercise bouts were more likely to reach a vigorous intensity when taking place at school and with friends/acquaintances/other people; whereas girls' sports and exercise bouts were more likely to reach a vigorous intensity when outdoors and alone. For boys and girls, bout durations were greater at school and with friends/acquaintances/other people than in other environments. Overall, environmental influences on the intensity but not duration of sports and exercise bouts appear to differ between boys and girls.     

Muscle Soreness Following Resistance Exercise With and Without Eccentric Contractions

The present study reported on translating the Exercise Identity Scale (EIS: Anderson &; Cychosz, 1994) into Greek and examining its psychometric properties and cross-cultural validity based on U.S. individuals' EIS responses. Using four samples comprising 33, 103, and 647 Greek individuals, including exercisers and nonexercisers, and a similar sample comprising 800 U.S. individuals, the concurrent validity, factor structure, internal reliability, test-retest reliability, external validity, gender invariance, and cross-cultural validity of the EIS responses were examined using confirmatory factor analytical procedures. The results supported the concurrent validity, an adequate unidimensional factor structure for the translated EIS and the internal reliability and test-retest reliability over a 6-week interval. Further, cross-gender configural, partial metric, partial strong factorial, and partial strict factorial invariance and cross-cultural configural and partial metric invariance supported the cross-cultural equivalence of the EIS versions. Moreover, the external validity of the translated EIS responses was also supported. Overall, the findings supported the validity of the exercise identity construct outside North American boundaries and the EIS items' equivalence, providing initial evidence for its cross-cultural applicability.