ABSTRACT
The present systematic review was compiled to analyze the effectiveness of High-intensity interval training (HIIT) protocols on the body composition of rodents with obesity. Databases were searched until February 2021 for experimental trials in rodents with a minimum duration of four weeks of HIIT and endpoints associated with obesity. The data were analyzed by meta-analysis performed for comparisons of body composition. Sensitivity analysis was performed to investigate the consistency of individual researches. Of all of the 524 studies found, only 14 were included. The analysis showed a significant reduction in body weight ([CI 95%: -8.35; -1.98] P ≤ 0.01), adiposity index ([IC 95%: -1.04; -0.80] P ≤ 0.01), and fat pads ([IC 95%: -0.59; -0.06] P ≤ 0.01). HIIT performed on treadmill or water was effective to reduce body weight (P < 0.05). In conclusion, HIIT attenuated both body weight and adiposity induced either by HFD (high-fat diet) or by GOM (genetic obese model), thereby inducing positive changes in body composition.
ABSTRACT
A mensuração do lactato sanguíneo com determinação do limiar anaeróbio é uma forma simples e difundida de avaliar o desempenho físico. O lactato é o produto final da glicólise anaeróbia, um dos processos geradores de energia no corpo humano, junto com os sistemas dos fosfagênios e aeróbio. A contribuição relativa de cada um deles para as demandas energéticas do músculo esquelético depende do tipo, intensidade e duração do exercício, e o lactato é uma forma de medir essa contribuição. Há intensa transferência de lactato entre tecidos e dentro das células musculares. O propósito desta revisão é interligar esses aspectos em uma estrutura coerente a partir da qual novas hipóteses possam ser exploradas. Foram consultados artigos das bases PubMed e Scielo usando os termos treinamento, performance, lactato e metabolismo e livros de fisiologia. O metabolismo sistêmico de lactato e a variação sanguínea do lactato, registrada em avaliações de desempenho, são aspectos inter-relacionados do mesmo processo fisiológico.
The measuring of blood lactate to determine anaerobic threshold is the commonest method to evaluate physical performance. Lactate is the final product of anaerobic glycolysis, one of the energy-producing processes in the human body, coupled to phosphagenic and aerobic systems. Since relative contribution of each for energy demands of the skeleton muscle depends on the type, intensity and duration of the exercise, lactate measures such contribution. There is intense transfer of lactate among tissues and within muscle cells. This review interlinks the above aspects within a coherent structure so that new hypotheses may be taken. Physiology textbooks and articles from PubMed and Scielo databases were consulted by employing the terms training, performance, lactate and metabolism. Lactate systemic metabolism and lactate blood variation registered in performance assessments are inter-related aspects of the same physiological process.
