868 resultados para Exercise Performance
Resumo:
BACKGROUND Prognostic classification of congestive heart failure (CHF) is difficult and only possible with the help of additional diagnostic tools. B-type natriuretic peptide (BNP) has been used as a diagnostic and prognostic marker for patients (pts) with CHF. In this study, the clinical value of BNP for stratification and treatment of pts with CHF was evaluated. PATIENTS AND METHODS 33 out-pts with CHF (age 57 +/- 12 years) were included. Left-ventricular (LV) ejection fraction (EF) was 27 +/- 8% (mean +/- SD) and NYHA-class 2.4 +/- 0.7. Following parameters were measured: BNP and sodium from blood samples, exercise performance from 6-minute walking test (6MWT, meters) (n = 18), LV end-diastolic diameter (LVEDD) and LV mass (LVM) from 2D-echocardiography (n = 33), as well as LV end-diastolic pressure (LVEDP, n = 23) and systemic vascular resistance (SVR, n = 20) from heart-catheterisation. Ten pts were hospitalised in the preceding 6 months because of worsening CHF or for optimisation of medical therapy. BNP was measured at the beginning and end of the hospital-stay. Follow-up was for 1 year. RESULTS Pts with a high NYHA-class had a higher BNP (pg/ml) than those with a low NYHA- class: NYHA I 51 +/- 20, II 281 +/- 223, III 562+/-346 and IV 1061 +/- 126 pg/ml (p = 0.002). BNP correlated with LVEDP (r = 0.50, p <0.02), SVR (r =0.49, p <0.03) and inversely with 6MWT (r =-0.60, p <0.009), LVEF (r = -0.49, p <0.004) and sodium (r = -0.36, p = 0.04). In the hospitalised pts, mean BNP (pg/ml) was 881 +/- 695 at admission,and 532 +/- 435 at discharge (n.s.). Decrease in BNPduring hospitalisation paralleled weight-loss and was significantly greater in patients with >1000 pg/ml BNP at admission (n = 5) as compared to the 5 patients with BNP <1000 (p <0.03). Patients with an adverse event during 1-year follow-up had significantly higher BNP both at steady-state (603 +/-359 pg/ml) and at time of decompensation than patients with a favourable outcome (227 +/- 218 pg/ml,p <0.001). CONCLUSIONS BNP correlates well with the clinical severity of CHF (NYHA-class) and is directly related to filling pressure (LVEDP), LV function(LVEF) and exercise performance (6 MWT). Furthermore, BNP has prognostic impact with regard to adverse clinical events.
Resumo:
We tested the predictions of Attentional Control Theory (ACT) by examining how anxiety affects visual search strategies, performance efficiency, and performance effectiveness using a dynamic, temporal-constrained anticipation task. Higher and lower skilled players viewed soccer situations under 2 task constraints (near vs. far situation) and were tested under high (HA) and low (LA) anxiety conditions. Response accuracy (effectiveness) and response time, perceived mental effort, and eye-movements (all efficiency) were recorded. A significant increase in anxiety was evidenced by higher state anxiety ratings on the MRF-L scale. Increased anxiety led to decreased performance efficiency because response times and mental effort increased for both skill groups whereas response accuracy did not differ. Anxiety influenced search strategies, with higher skilled players showing a decrease in number of fixation locations for far situations under HA compared with LA condition when compared with lower skilled players. Findings provide support for ACT with anxiety impairing processing efficiency and, potentially, top-down attentional control across different task constraints.
Resumo:
Objective measurements of physical fitness and pulmonary function are related individually to long-term survival, both in healthy people and in those who are ill. These factors are furthermore known to be related to one another physiologically in people with pulmonary disease, because advanced pulmonary disease causes ventilatory limitation to exercise. Healthy people do not have ventilatory limitation to exercise, but rather have ventilatory reserve. The relationship between pulmonary function and exercise performance in healthy people is minimal. Exercise performance has been shown to modify the effect of pulmonary function on mortality in people with chronic obstructive pulmonary disease, but the relationship between these factors in healthy people has not been studied and is not known. The purpose of this study is to quantify the joint effects of pulmonary function and exercise performance as these bear on mortality in a cohort of healthy adults. This investigation is an historical cohort study over 20 years of follow-up of 29,624 adults who had complete preventive medicine, spirometry and treadmill stress examinations at the Cooper Clinic in Dallas, Texas.^ In 20 years of follow-up, there were 738 evaluable deaths. Forced expiratory volume in one second (FEV$\sb1$) percent of predicted, treadmill time in minutes percent of predicted, age, gender, body mass index, baseline smoking status, serum glucose and serum total cholesterol were all significant, independent predictors of mortality risk. There were no frank interactions, although age had an important increasing effect on the risk associated with smoking when other covariates were controlled for in a proportional-hazards model. There was no confounding effect of exercise performance on pulmonary function. In agreement with the pertinent literature on independent effects, each unit increase in FEV$\sb1$ percent predicted was associated with about eight tenths of a percent reduction in adjusted mortality rate. The concept of physiologic reserve is useful in interpretation of the findings. Since pulmonary function does not limit exercise tolerance in healthy adults, it is reasonable to expect that exercise tolerance would not modify the effect of pulmonary function on mortality. Epidemiologic techniques are useful for elucidating physiological correlates of mortality risk. ^
Resumo:
Various exercises are used to retrain the abdominal muscles in the management of low back pain and other musculoskeletal disorders. However. few studies have directly investigated the activity of all the abdominal muscles or the recruitment of regions of the abdominal muscles during these manoeuvres. This study examined the activity of different regions of transversus abdominis (TrA), obliquus internus (OI) and externus abdominis (OE), and rectus abdominis (RA), and movement of lumbar spine, pelvis and abdomen during inward movement of the lower abdominal wall, abdominal bracing, pelvic tilting, and inward movement of the lower and upper abdominal wall. Inward movement of the lower abdominal wall in supine produced greater activity of TrA compared to OI. OE and RA. During posterior pelvic tilting. middle OI was most active and with abdominal bracing. OE was predominately recruited. Regions of TrA were recruited differentially and in inverse relationship between lumbopelvic motion and TrA electromyography (EMG) was found. This study indicates that inward movement of the abdominal wall in supine produces the most independent activity of TrA relative to the other abdominal muscle, recruitment varies between regions of TrA, and observation of abdominal and lumbopelvic motion may assist in evalation of exercise performance. (c) 2004 Elsevier Ltd. All rights reserved.
Resumo:
High-intensity exercise leads to reductions in muscle substrates (ATP, PCr, and glycogen) and a subsequent accumulation of metabolites (ADP, Pi, H+, and M2+) with a possible increase in free radical production. These factors independently and collectively have deleterious effects on muscle, with significant repercussions on high-intensity performance or training sessions. The effect of carnosine on overcoming muscle fatigue appears to be related to its ability to buffer the increased H+ concentration following high-intensity work. Carnosine, however, has other roles such as an antioxidant, a metal chelator, a Ca2+ and enzyme regulator, an inhibitor of protein glycosylation and protein-protein cross-linking. To date, only 1 study has investigated the effects of carnosine supplementation (not in pure form) on exercise performance in human subjects and found no improvement in repetitive high-intensity work. Much data has come from in vitro work on animal skeletal muscle fibers or other components of muscle contractile mechanisms. Thus further research needs to be carried out on humans to provide additional understanding on the effects of carnosine in vivo.
Resumo:
This study assessed the knowledge, prevalence, and quantity of caffeine use by athletes competing at the 2005 Ironman Triathlon World Championships. Caffeine-related questionnaires were self-administered to 140 (105 male and 35 female, 40.3 +/- 10.7 y) athletes representing 16 countries. Fifty of these athletes further consented to immediate post-race blood samples for analysis of plasma caffeine and paraxanthine using high-performance liquid chromatography (HPLC). Seventy-two percent of 70 athletes correctly identified caffeine as being an unrestricted substance in triathlon. The majority of athletes [125 (89%)] were planning on using a caffeinated substance immediately prior to or throughout the race. Cola drinks (78%), caffeinated gels (42%), coffee (usually pre-race) (37%), energy drinks (13%), and NoDoz tablets (9%) were the most popular caffeinated choices. Mean standard deviation (and range) post race plasma caffeine and paraxanthine levels were 22.3 +/- 20 mu mol/L (1.7 to 98.4) and 9.4 +/- 6 mu mol/L (1.8 to 28.9), respectively. Seven athletes (14%) finished with plasma caffeine levels >= 40 mu mol/L. Plasma values from elite athletes did not differ from age group competitors. Despite the prevalence of its consumption and the training experience of this athletic group, over one quarter of athletes remained either confused or uninformed about caffeine's legality. Levels of plasma caffeine taken immediately post race indicated that athletes typically finish with quantities of caffeine that have been shown to improve endurance performance (i.e., approximate to 20 mu mol/L or a dose of >= 3 mg/kg body weight).
Resumo:
Our aim was to determine the normative reference values of cardiorespiratory fitness (CRF) and to establish the proportion of subjects with low CRF suggestive of future cardio-metabolic risk.
Resumo:
Stories by children’s writer Dr. Seuss have often been utilised as non-traditional narrative reflections regarding the issues of ethics and morality (Greenwood, 2000). Such case studies are viewed as effective teaching and learning tools due to the associated analytical and decision-making frameworks that are represented within the texts, and focus upon the exploration of universally general virtues and approaches to ethics (Hankes, 2012). Whilst Dr. Seuss did not create a story directly related to the sport, exercise or performance domains, many of his narratives possess psychological implications that are applicable in any situation that requires ethical consideration of the thinking and choices people make. The following exploration of the ‘ethical places you’ll go’ draws upon references to his work as a guide to navigating this interesting and sometimes challenging landscape for sport, exercise, and performance psychologists (SEPP).
Resumo:
Objective: To evaluate the feasibility, reliability and acceptability of the mini clinical evaluation exercise (mini-CEX) for performance assessment among international medical graduates (IMGs). Design, setting and participants: Observational study of 209 patient encounters involving 28 IMGs and 35 examiners at three metropolitan teaching hospitals in New South Wales, Victoria and Queensland, September-December 2006. Main outcome measures: The reliability of the mini-CEX was estimated using generatisability (G) analysis, and its acceptability was evaluated by a written survey of the examiners and IMGs. Results: The G coefficient for eight encounters was 0.88, suggesting that the reliability of the mini-CEX was 0.90 for 10 encounters. Almost half of the IMGs (7/16) and most examiners (14/18) were satisfied with the mini-CEX as a learning tool. Most of the IMGs and examiners enjoyed the immediate feedback, which is a strong component of the tool. Conclusion: The mini-CEX is a reliable tool for performance assessment of IMGs, and is acceptable to and well received by both learners and supervisors.
Resumo:
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Resumo:
Aim: To assess the contribution of a multimodal exercise program on the sleep disturbances (SD) and on the performance of instrumental activities daily living (IADL) in patients with clinical diagnosis of Alzheimer's disease (AD) and Parkinson's disease patients (PD). Methods: A total of 42 consecutive patients (23 training group, 19 control group) with PD and 35 demented patients with AD (19 trained group, 16 control group) were recruited. Participants in both training groups carried out three 1-h sessions per week of a multimodal exercise program for 6 months. The Pfeffer Questionnaire for Instrumental Activities and the Mini-Sleep Questionnaire were used to assess the effects of the program on IADL and SD respectively. Results: Two-way ancova showed interactions in IADL and SD. Significant improvements were observed for these variables in both intervention groups, and maintenance or worsening was observed in control groups. The analysis of effect size showed these improvements. Conclusion: The present study results show that a mild to moderate intensity of multimodal physical exercises carried out on a regular basis over 6 months can contribute to reducing IADL deficits and attenuating SD. © 2013 Japan Geriatrics Society.
Resumo:
Despite its active embrace of trade liberalization and the maintainance of relatively open economies, CARICOM trade performance both within the region and extraregionally has been poor. The nexus between bilateral Free Trade Agreements (FTAs), Partial Scope Agreements (PSAs) and preferential trade arrangements, which was intended to assist in compensating for the small size of domestic and regional markets, while providing an additional tier of trade and economic integration, has thus far failed to deliver its intended results. This paper makes this conclusion in assessing the performance of these extraregional trade agreements and sheds light on issues not often discussed.