Efeitos agudos da atividade contra-resistência sobre o gasto energético: revisitando o impacto das principais variáveis

Abstract

INTRODUCTIONComprehension of the factors that affect energy balance is of key importance in understanding the regulation of body mass. Energy balance is determined, on the one hand, by energy consumption and, on the other, by energy expenditure. When these factors are not in equilibrium, it may result in an excessive accumulation or reduction of the energy stored endogenously as body fat. However, obesity is the most frequent result of the unbalance between food ingestion and energy expenditure.The number of overweight persons has been increasing in Brazil and in many other parts of the world. Recent results revealed that, among the population residing in Rio de Janeiro, 44% of men and 33% of women between 26 and 45 year of age were overweight or obese (1) .Obesity, according to the World Health Organization (2) , is considered a public health problem that leads to serious social, psychological and physical consequences, and is associated to greater risks of morbimortality by non-transmittable chronic diseases. Individuals with a body mass index equal to or above 30 kg.m -2 are classified as obese (2) . Although the causes of this phenomenon are multifactorial (3) and therefore difficult to be established, the scientific community considers it wise to investigate ways to increase daily energy expenditure in order to reduce or control the prevalence of obesity.Energy expenditure of physical activity is the most variable component of total energy expenditure. It can be voluntarily increased, contributing to a negative energy balance when food intake is also controlled (4) . Programs combining energy restriction and aerobic exercises have been, for a long time, indicated for weight loss (5,6) . This is justified by the role of physical activity in Acute effects of resistance exercise on energy expenditure: revisiting the impact of the training variables ABSTRACTThe prevalence of obese and overweight persons is growing, both in Brazil and in other parts of the world. It is, therefore, important to establish strategies that will try to control this. The combination of energy restriction and aerobic exercises has long been recognized as an effective means of controlling body composition; on the other hand, the impact of resistance exercises on weight loss is still questionable. Thus, the purpose of this review was to discuss the effect of resistance exercises on energy expenditure, considering each of its related variables -intensity, duration, number of sets, interval between sets, movement velocity and type of training (circuit or multiple sets). The reviewed studies showed that resistance exercises may induce an acute increase in energy expenditure, through the energy cost of the exercise session itself and through the excess post-exercise oxygen consumption (EPOC). It is also recognized that the many variables related to resistance exercises influence the results in different ways. Number of repetitions, load, rest interval between sets and number of sets, when manipulated in order to increase volume or intensit...

The Effects of Physical Activity on Serum Visfatin Level: A Literature Review

“…17 Each of these resistance protocols have different metabolic and hormonal responses regarding the difference in the intensity of exercise and rest time between sets, one of the factors in determining energy expenditure during resistance exercise. 18,19 Kraemer et al examined the levels of certain hormones including growth hormone, and cortisol as well as lactate level in response to resistance exercise with 6 different protocols. 20 Studies show that intensity and duration of exercise can affect gene expression and plasma levels of these hormones.…”

“…21,22 Hormonal and metabolic responses to resistance exercise are complex processes and an integrated system for signalling to a large group of target cells. 18 As one of the factors, 23 visfatin and insulin are affected in response to exercise. Considering the role of resistance training in improving insulin sensitivity, 24 comparison of visfatin and its possible impact on the response to resistance exercise protocols can show important potential mechanisms on the role of visfatin in insulin resistance.…”

Efeito do consumo excessivo de oxigênio após exercício e da taxa metabólica de repouso no gasto energético

“…Ponderal reduction is also related with chronic alterations of physical activities, that is, of the resting metabolic rate (RMR). The RMR is defined as the energetic cost necessary to the physiological processes maintenance in the post-absorptive state, reaching up to 60-70% of the total energetic cost, depending on the physical activity level (21) . The high interest on ponderal reduction is due to the fact that obesity is currently considered by the World Health Organization a public health problem (22) .…”

“…An estimate considering the current prevalence of obese individuals highlights that if such proportion remains, in the year 2230 100% of the North-American population will be obese (23) . Analyzing the Brazilian reality, Meirelles and Gomes (21) showed that in Rio de Janeiro 44% of the men and 33% of the women in the age group from 26 to 45 years present overweight or obesity.…”

“…Although obesity is related to several causes, namely genetic; physiological; metabolic; environmental; emotional and cultural ones, all the attention dedicated to the increase of the daily energetic cost is highly valid, once the energetic balance is partly determined by the energy consumption and partly by the energy cost (21,24) . Therefore, a positive energetic imbalance may lead to excessive energy accumulation stored as body fat.…”