Aging is a natural, multifactorial and multiorganic phenomenon wherein there are gradual physiological and pathological changes over time. Aging has been associated with a decrease of autophagy capacity and mitochondrial functions, such as biogenesis, dynamics, and mitophagy. These processes are essential for the maintenance of mitochondrial structural integrity and, therefore, for cell life, since mitochondrial dysfunction leads to an impairment of energy metabolism and increased production of reactive oxygen species, which consequently trigger mechanisms of cellular senescence and apoptotic cell death. Moreover, reduced mitochondrial function can contribute to age-associated disease phenotypes in model organisms and humans. Literature data show beneficial effects of exercise on the impairment of mitochondrial biogenesis and dynamics and on the decrease in the mitophagic capacity associated to aging. Thus, exercise could have effects on the major cell signaling pathways that are involved in the mitochondria quality and quantity control in the elderly. Although it is known that several exercise protocols are able to modify the activity and turnover of mitochondria, further studies are necessary in order to better identify the mechanisms of interaction between mitochondrial functions, aging, and physical activity, as well as to analyze possible factors influencing these processes.
To reduce transmission of the coronavirus, the Brazilian government adopted containment measures to control the virus’ spread, including limitations to the practice of physical activity. It was aimed to analyze the effects of COVID-19 quarantine on physical activity levels, energy expenditure, quality of life, and level of stress in a sample of the Brazilian population. The sample included 426 participants (7 to 80 years). The International Physical Activity Questionnaire, Short form survey-36 (SF-36), and Stress Perception Scale, were used to assess the level of physical activity, quality of life and stress, respectively. The anthropometric data was used to the assessment of body mass index and basal metabolic rate. Body weight increased significantly in all sample (p < 0.05). During the pandemic, 84% of the sample indicated a low level of physical activity. Furthermore, weekly energy expenditure decreased significantly in all age groups during the pandemic (children p < 0.0001; adolescents: p < 0.0001; adults p < 0.001, and elderly p < 0.0001). All aspects of quality of life, significantly reduced in both sexes in all age groups (p < 0.05). With the exception of children, stress levels increased significantly during the pandemic (adolescents: male: p = 0.003, female: p < 0.05; adults: male: p = 0.003, female: p = 0.01, and elderly: male: p = 0.02, female: p = 0.03). Findings from the present study suggests that COVID-19 social isolation has negatively affected Brazilian’ physical activity and quality of life.
OBJETIVO: Determinar a prevalência de sobrepeso e obesidade, além de verificar a influência da massa corporal nos níveis glicêmicos dos professores da UFV. MÉTODOS: Estudo observacional com delineamento transversal em amostra de professores da UFV (n = 145), com idades entre 25 e 67 anos. A coleta de dados envolveu as medidas antropométricas de estatura, massa corporal (MC), dobras cutâneas, circunferência abdominal (CA) e perímetros de cintura e quadril. Foi também realizado análise de microamostras sanguíneas de glicemia de jejum. A análise estatística constituiu na exploração descritiva e no cálculo das prevalências das variáveis estudadas. Para verificação da influência da MC nos níveis glicêmicos, utilizou-se o teste de correlação de Pearson. RESULTADOS: O percentual de gordura aponta que 39% da população apresentaram valores que estavam na faixa que os classificam como insuficientes. Valores de CA acima do limite superior foram encontrados em 43,69% dos homens, e em 54,76% das mulheres. Quanto ao índice cintura-quadril (ICQ), 18,62% dos avaliados apresentaram risco alto ou muito alto para doenças cardiovasculares. A prevalência de excesso de peso foi de 51,04%. Foram encontrados valores anormais de glicemia em 4,83% da população. As correlações entre a MC, IMC e CA com os níveis glicêmicos foram positivas, porém apresentaram-se fracas. Somente o IMC no sexo masculino e o ICQ em ambos os gêneros não apresentaram correlação. CONCLUSÃO: A prevalência de sobrepeso e obesidade encontrada no presente estudo se mostrou elevada; porém, a massa corporal não demonstrou forte influência sobre os níveis glicêmicos dos professores da UFV.
Background: In Paralympic powerlifting (PP), athletes with and without spinal cord injury (SCI) compete in the same category. Athletes with SCI may be at a disadvantage in relation to the production of muscle strength and the execution of motor techniques. Objective: To analyze the indicators force, dynamic and static, at different intensities, on performance in athletes with and without SCI. Methods: The sample was composed of two groups of PP athletes: SCI (30.57 ± 4.20 years) and other deficiencies (OD; 25.67 ± 4.52 years). Athletes performed a test of maximum isometric force (MIF), time to MIF (Time), rate of force development (RFD), impulse, variability and fatigue index (FI), dynamic tests Mean Propulsive Velocity (MPV), Maximum Velocity (Vmax) and Power. Results: There were differences in the SCI in relation to OD, 50% 1RM (p < 0.05), in relation to MPV and Vmax. There were no differences in the static force indicators. Regarding EMG, there were differences between the SCI triceps in relation to the previous deltoid (p = 0.012). Conclusion: We concluded that the static and dynamic strength indicators are similar in Paralympic powerlifting athletes with spinal cord injury and other disabilities.
The results of this study indicate that there was an improvement in the measures of strength in EG, and that there was a correlation between improvements in strength and quality of life in these patients who had previously suffered a stroke at least one year prior to study.
The aim of the present study was to analyze the effect of creatine (Cr) supplementation on peak torque (PT) and fatigue rate in Paralympic weightlifting athletes. Eight Paralympic powerlifting athletes participated in the study, with 25.40 ± 3.30 years and 70.30 ± 12.15 kg. The measurements of muscle strength, fatigue index (FI), peak torque (PT), force (kgf), force (N), rate of force development (RFD), and time to maximum isometric force (time) were determined by a Musclelab load cell. The study was performed in a single-blind manner, with subjects conducting the experiments first with placebo supplementation and then, following a 7-day washout period, beginning the same protocol with creatine supplementation for 7 days. This sequence was chosen because of the lengthy washout of creatine. Regarding the comparison between conditions, Cr supplementation did not show effects on the variables of muscle force, peak torque, RFD, and time to maximum isometric force (p > 0.05). However, when comparing the results of the moments with the use of Cr and placebo, a difference was observed for the FI after seven days (U3: 1.12; 95% CI: (0.03, 2.27); p = 0.02); therefore, the FI was higher for placebo. Creatine supplementation has a positive effect on the performance of Paralympic powerlifting athletes, reducing fatigue index, and keeping the force levels as well as PT.
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