Efeitos da caminhada sobre o balanço energético em mulheres obesas

• Autor(a) principal: Silva, Rafael Pacheco
• Data de Publicação: 2012
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/3476
• topic: Obesidade; Balanço energético; Caminhada; Obesity; Energy balance; Walk; CNPQ::CIENCIAS DA SAUDE::EDUCACAO FISICA

This work was proposed with the main objective of evaluating the effects of walking on energy balance in obese women, and to this end, we conducted a review and two original articles in sequence. In the review, was verified that obesity epidemic has grown worldwide, both in adults and adolescents and has been reported as an independent factor for the risk of appearence and development of cardiometabolic diseases of order, besides being associated with other risk factors, such as dislipidemies, diabetes mellitus and hypertension. There are several methods for the diagnosis of obesity, varying their operating costs and possibilities of application in epidemiologic research. In recent years, the focus of research on excess body weight has been the distribution of fat and its relationship with inflammatory mechanisms, which mainly mediated by concentrations of C-reactive protein (CRP), leptin and cytokines, such as the tumor necrosis factor α (TNF-α), interleukin-6 (IL-6), adiponectin and plasminogen activator inhibitor-1 (PAI-1). The prevention and treatment strategies adopted have sought, in addition to the techniques commonly used at all times monitor adherence to treatment, avoiding possible compensatory responses and re-gain weight after programs of diet and physical activity interventions. Obese women choose to walk at a comfortable pace and with less energy expenditure. Thus, the main of the original article 1 was to compare the energy cost per distance in different speeds of walking. 13 obese women (IMC=33,82 ± 2,95 kg/m2) and sedentary had been voluntary in the study. To determine the energy cost per distance (m/min), we measured the respiratory exchanges in a treadmil protocol that consisted of 5 stages of training of 4 minutes, with 4 minutes of rest, increasing speeds (3,0, 4,0, 5,0, 6,0 km/h and the self-selected speed of walking - VCAS). We measured the VCAS through the average of the time to cover a track of 50 meters of length. The energy expenditure per distance was defined as: (gross economy = VO2 [ml/kg.min] divided by the speed [m/min]). VO2 and FC increased according to the increase of the speed at the treadmill. The average VCAS gotten by the volunteers was 4,8 km/h. The speed of 3,0 km/h presented greater value of gross economy in relation to 4,0, 5,0, VCAS and 6,0 km/h (0,089, against 0,076, 0,073, 0,074 and 0,078 ml/kg.m). We concluded that the VCAS represents the lesser cost of energy per distance, between five different speeds, in obese and sedentary women. Moreover, 3,0 km/h represents the speed that promotes the biggest energy expenditure per covered distance. The ineffectiveness of exercise programs to promote weight loss has been questioned, however the analysis of variables related to habitual physical activity (HPA) and food intake components are not considered in several studies was the object of study in original article 2. Thus, the mais was to investigate compensatory responses on the energy balance and body composition of obese women. Eight obese women underwent a walking program for 8 weeks (4 supervised and unsupervised 4). In the pre-intervention (PRE), after 4 weeks (4W) and after 8 weeks (POST) intervention, the HPA was monitored for 7 days with the accelerometer ActiGraph GT3X and food intake was verified by 3 day-record. Were performed anthropometry and fat percentage, as measured by tetrapolar bioimpedance. In PRE and POST, were estimated maximum oxygen uptake (VO2max), by indirect calorimetry, in addition to glucose, total cholesterol and fractions, and triglycerides. ANOVA with post hoc Tukey test was performed for variables measured in PRE, 4W and POST, paired t-test for variables measured in PRE and POST. No differences were observed in body composition. Seven women increased their caloric intake after 4W. Comparing the differences between periods (Δ), differences were found between Δ PRE-4W (253 kcal / day) x ΔPOST-4W (-42 kcal / day) (p = 0.014) and Δ PRE-POST (211 kcal / day ) x ΔPOST-4W (-42 kcal / day) (p = 0.033). The mean caloric intake per week in PRE, 4W and POST was 9620,33 ± 2368,70, 11394,39 ± 2004,59 and 11097.91 ± 1477,53 kcal, respectively. In the HPA, there were differences in PRE and POST in relation to 4W (274423 ± 126044 and 224352 ± 78669 vs. 224352 ± 78669 counts, respectively) and significant increase in VO2max (21,13 ± 3,58 and 24,40 ± 3,22 ml.O2.kg- 1.min-1) and reducing LDL (147,00 ± 24,01 and 130,45 ± 20,81 mg.dL-1). We concluded that, despite the benefits to health and fitness, the walking program conducted in this study did not contribute to significant changes in body composition in obese women, due to compensatory responses related to increased food intake and decreased physical activity.