Comportamento sedentário: conceito, implicações fisiológicas e os procedimentos de avaliação

Alves, RR, Viana, RB, Silva, MH, Guimarães, TC, Vieira, CA, Santos, DdAT, and Gentil, PRV. Postactivation potentiation improves performance in a resistance training session in trained men. J Strength Cond Res 35(12): 3296–3299, 2021—This study aims to analyze the influence of postactivation potentiation (PAP) on performance during a resistance training (RT) session in trained individuals. Fourteen trained men (25.0 ± 3.5 years; 89.9 ± 16.3 kg; 1.77 ± 0:08 m; 28.0 ± 4.0 kg·m⁻²; and 5 ± 4 years of RT experience) were tested in 2 situations: with PAP and without PAP (CON). Both situations involved 3 sets of the bench press exercise performed to muscle failure at 75% of the 1 repetition maximum load and with 1.5-minute interval between sets. Total work was greater (p < 0.001) for PAP (1,601 ± 504 kg) than for CON (1,379 ± 364 kg). The number of repetitions performed in the first and second sets of PAP (11.5 ± 3.1 and 6.5 ± 1.9, respectively) were greater (p < 0.05) than those performed in CON (10.4 ± 2.7, 5.5 ± 1.8, respectively). No significant difference was found in the number of repetitions in the last set between the situations. The present study suggests that PAP might be beneficial to improve total work and performance during multiple sets of RT in trained men. Therefore, PAP might be used during RT to promote higher total work and potentially increase results over long term. Thus, the protocol can use in sports centers, fitness centers, and gyms per coaches and athletes to increase performance and total work in trained individuals.

The aim of the present study was to investigate the relationship of dynapenia combined with sedentary behavior (SB) on the risk of mortality in older adults living in a Brazilian community. A total of 322 participants aged ≥ 60 years from the ELSIA (Longitudinal Study of Elderly Health in Alcobaça) prospective cohort were included. Dynapenia was diagnosed when the handgrip strength was < 27 ​kg for men and < 16 ​kg for women. The exposure time to SB was assessed considering the total time spent sitting during one day in the week and one day on the weekend. When combined with dynapenia, we derived the construction of four groups: best behavior (absence of dynapenia and low SB), intermediate behavior (absence of dynapenia and high SB; presence of dynapenia and low SB) and worst behavior (presence of dynapenia and high SB). Mortality was assessed by the follow-up time until death and/or censorship. During the 5-year follow-up of the study, 55 participants progressed to death. In the adjusted models, the dynapenia and the time spent exposed to SB were analyzed in a combined way, the older adults with worse behavior (high SB and dynapenia) had higher risk ratios for mortality (hazard ratio 2.46; 95% confidence interval 1.01-5.97) than the best behavior group. Older adults with dynapenia are at greater risk for all-cause mortality, which is aggravated by the addition of longer exposure to SB.

This paper aims to analyse whether time spent in sedentary behaviour was a discriminant criterion for frailty in older adults. This was a cross-sectional study conducted in a sample of 457 elderly individuals aged ≥60 years. Frailty was defined as the presence of three or more of the following criteria: Unintentional weight loss, low walking speed at a 4.57 m course, reduced manual grip strength, exhaustion and insufficient physical activity level. Participants were classified into two groups: Non-frail or frail. Exposure to sedentary behaviour was assessed by the time spent sitting during a typical week, according to the adapted version of the International Physical Activity Questionnaire. Descriptive (mean, frequency) and inferential statistics (Poisson regression, Pearson’s Chi-square, Receiver Operating Characteristic Curve) were used to analyse the data, comparing them to the time-related areas exposed to sedentary behaviour by gender and the presence of fragility. The prevalence of frailty was 22.1% (n = 101). The most accurate cut-off points of sitting time for predicting frailty were >495 min/day (men) or >536 min/day (women). Time spent in sedentary behaviour can be used to indicate fragility in the elderly of both sexes.

This study aimed to compare the anthropometric profile and physical fitness of young judo and wrestling athletes. Twenty-four young athletes (judo (n = 13) and wrestling (n = 11)) participated in this study. The first visit involved anthropometric and flexibility evaluation, abdominal endurance test, upper limbs resistance and cardiorespiratory test. After 48 h, horizontal jump test (HJT), vertical jump test (VJT), medicine ball throw test (MBT), chin-up test (CUT), chin-up isometric test (CUIT) and the anaerobic resistance test were performed. Judo athletes presented greater values for body mass (p = 0.020), height (p = 0.010), and body mass index (p = 0.026) than wrestlers. Judo athletes also performed better for abdominal endurance (p = 0.044), upper limb resistance tests (p < 0.001), VJT (p = 0.022) and MBT (p = 0.023) than wrestling athletes. These results suggest that young judo athletes presented a higher performance in abdominal endurance, upper limbs resistance, HJT, VJT and MBT than wrestling athletes, suggesting that strength and conditioning are related to modality specificity.