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Performance Capacity (performance + capacity)
Selected AbstractsHorn size predicts physical performance in the beetle Euoniticellus intermedius (Coleoptera: Scarabaeidae)FUNCTIONAL ECOLOGY, Issue 4 2005S. P. LAILVAUX Summary 1In many animals, the size of secondary sexual ornaments is known to be related to the probability of victory in fights between males, and hence to fighting ability. However, few studies have attempted to link fighting ability to any physical performance measures. 2Here we show that horn size in the dung beetle Euoniticellus intermedius accurately predicts two types of whole-organism performance, independent of body size, that are likely to play an important role in male contests: the force required to pull a beetle out of a tunnel, and the distance the beetle was able to run before exhaustion (maximum exertion). 3Body length is also a statistically significant predictor of pulling force, but not of exertion, suggesting that horn size is a more reliable predictor of performance than body size alone, a result that is consistent with a previous finding that horn size becomes more important in determining victory in male,male contests as body size increases. 4This study is the first to establish direct links between whole-organism performance abilities, male armaments and fighting ability in the same species. Our findings suggest that physiological performance capacities are important factors underlying the evolution of signal expression in E. intermedius, and should be considered in future studies of the evolution of animal signalling. [source] Effects of inhalation of albuterol sulphate, ipratroprium bromide and frusemide on breathing mechanics and gas exchange in healthy exercising horsesEQUINE VETERINARY JOURNAL, Issue 3 2001W. M. BAYLY Summary The possibility that pre-exercise inhalation of a bronchodilator by healthy horses could improve their mechanics of breathing and enhance performance was investigated. Ipratropium bromide (0.35 ,g/kg bwt; n = 7) was administered by nebulisation 30 min before exercise and frusemide (1 mg/kg bwt; n = 6) was given in the same manner 2 h before exercise. Albuterol sulphate (360 and 720 ,g; n = 7) were administered with a metered dose inhaler 2 h before exercise. Each drug was investigated independently of the others using cross-over protocols. Horses completed incremental exercise tests and oxygen consumption, carbon dioxide production, arterial blood gases, heart rate and measures of breathing mechanics including total pulmonary resistance (RL) and nasopharyngeal resistance (RU) were determined for each exercise intensity. The resistance of the lower airways was calculated subsequently from the difference between RL and RU. None of the drugs tested had an effect on any of the variables measured, possibly because maximal bronchodilation is stimulated in healthy horses by the normal sympathoadrenergic response to exercise. Therefore, the pre-exercise inhalation of a bronchodilator by a healthy horse is unlikely to improve performance capacity. [source] Bias against overweight job applicants: Further explorations of when and whyHUMAN RESOURCE MANAGEMENT, Issue 2 2007Lisa M. Finkelstein We investigated the impact of job candidate weight (average or overweight) on several job-related ratings following a videotaped mock interview. In ad-dition to weight, we manipulated the race of the applicant, level of job qual-ifications, and type of job (e.g., public or private contact). We also measured the effect of rater race and negative affect on multiple work-relevant ratings. Weight, applicant race, job qualifications, and job type each had a modest but significant impact on ratings of hireability, performance capacity, adapt-ability, and interpersonal skills, in varying combinations. The implications of these results for practice and future research are provided. © 2007 Wiley Pe-riodicals, Inc. [source] The fitness advantage of a high-performance weaponBIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 4 2009JERRY F. HUSAK Weapons used in combat between males are usually attributed to sexual selection, which operates via a fitness advantage for males with weapons of better ,quality'. Because the performance capacity of morphological traits is typically considered the direct target of selection, Darwin's intrasexual selection hypothesis can be modified to predict that variation in reproductive success should be explained by variation in performance traits relevant to combat. Despite such a straightforward prediction, tests of this hypothesis are conspicuously lacking. We show that territorial male collared lizards with greater bite-force capacity sire more offspring than weaker biting rivals but exhibit no survival advantage. We did not detect stabilizing or disruptive selection on bite-force capacity. Taken together, these results support the hypothesis that superior weapon performance provides a fitness advantage through increased success in male contests. Sexual selection on weapon performance therefore appears to be a force driving the evolution and maintenance of sexual dimorphism in head shape. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society, 2009, 96, 840,845. [source] Adaptations Of Skeletal Muscle To Prolonged, Intense Endurance TrainingCLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 3 2002John A Hawley SUMMARY 1. Endurance exercise induces a variety of metabolic and morphological responses/adaptations in skeletal muscle that function to minimize cellular disturbances during subsequent training sessions. 2. Chronic adaptations in skeletal muscle are likely to be the result of the cumulative effect of repeated bouts of exercise, with the initial signalling responses leading to such adaptations occurring after each training session. 3. Recently, activation of the mitogen-activated protein kinase signalling cascade has been proposed as a possible mechanism involved in the regulation of many of the exercise-induced adaptations in skeletal muscle. 4. The protein targets of AMP-activated protein kinase also appear to be involved in both the regulation of acute metabolic responses and chronic adaptations to exercise. 5. Endurance training is associated with an increase in the activities of key enzymes of the mitochondrial electron transport chain and a concomitant increase in mitochondrial protein concentration. These morphological changes, along with increased capillary supply, result in a shift in trained muscle to a greater reliance on fat as a fuel with a concomitant reduction in glycolytic flux and tighter control of acid,base status. Taken collectively, these adaptations result in an enhanced performance capacity. [source] Normal physical working capacity in prepubertal children with type 1 diabetes compared with healthy controlsACTA PAEDIATRICA, Issue 10 2005Elsa Heyman Abstract Background: Exercise testing has become a valuable help for the physician to examine the influence of recommended exercise training on physical fitness. However, the question as to how diabetic prepubertal children differ from their non-diabetic peers in their performance capacity has only partial and sometimes conflicting answers in the literature. Aim and methods: The aim of the current study was thus to evaluate aerobic fitness during an incremental submaximal test (measure of the Physical Working Capacity 170 (PWC170)) in 17 well-controlled prepubertal insulin-dependent diabetic boys aged 8.5,13 y. Eighteen healthy prepubertal boys matched for age, body size and physical activity served as controls. Part of the method was to check capillary blood glucose level in the diabetic patients and in nine of the healthy subjects throughout the exercise. Results: From this experiment it appeared that the level of physical fitness was similar in diabetic and healthy boys (PWC170 2.28±0.09 vs 2.37±0.13 W·kg,1). While glucose homeostasis was well maintained in the healthy group, diabetic children showed a marked fall in blood glucose during the exercise. In addition, the PWC170 level correlated significantly with the estimate of energy expenditure attributed to vigorous activities in the diabetic boys. Conclusion: By studying the responses to incremental exercise there is growing evidence that normal physical fitness is preserved in diabetic prepubertal boys given appropriate involvement in physical activity. [source] | |||||||||||||