Effects of Resistance Training at Different Loads on Inflammatory Biomarkers, Muscle Mass, Muscular Strength, and Physical Performance in Postmenopausal Women.

ABSTRACT: Carneiro, MAS, de Oliveira Júnior, GN, de Sousa, JFR, Murta, EFC, Orsatti, CL, Michelin, MA, Cyrino, ES, and Orsatti, FL. Effects of resistance training at different loads on inflammatory biomarkers, muscle mass, muscular strength, and physical performance in postmenopausal women. J Strength Cond Res 36(6): 1582-1590, 2022-It has been suggested that the effect of resistance training (RT) on circulating proinflammatory biomarkers may be dependent on muscle mass gain. A few recent studies have suggested that lower-load RT (LLRT; loads <50% of 1 repetition maximum [1RM] and repetition performed until, or close to, voluntary concentric failure) may be superior to higher-load RT (HLRT; loads >70% of 1RM) in increasing muscle mass. Hence, this study aimed to test whether LLRT is superior to HLRT for increasing muscle mass (total fat-free mass [TFFM] and leg fat-free mass [LFFM]) and improving circulating inflammatory biomarkers (interleukin [IL]-6, IL1-ra, tumor necrosis factor [TNF]-α, and extracellular heat shock protein [eHSP]70) in postmenopausal women (PW) (primary outcome). The secondary outcome was to compare the changes in muscular strength and physical performance (4-meter walking test [4-M], timed-up-and-go [TUG] test, and sit-to-stand [STS] test) between the LLRT and HLRT. The PW were randomized into 2 groups: LLRT (n = 14; loads necessary to perform 30-35 repetitions) and HLRT (n = 15; loads necessary to perform 8-12 repetitions). The greater magnitude of increase in LFFM (p = 0.033) was observed in LLRT when compared with HLRT. Moreover, there was a trend for a greater increase in TFFM in LLRT over HLRT (p = 0.070). However, there were similar improvements in TNF-α and muscular strength (p < 0.001). Furthermore, there was no significant difference between the RT schemes on IL-6, IL-1ra, and eHSP70 levels. Thus, although performing LLRT until, or close to, voluntary concentric failure seems to provide a greater stimulus for an increase in muscle mass than HLRT, it does not seem to affect the responses in circulating inflammatory biomarkers, muscular strength, and physical performance in PW.

Effect of whole-body resistance training at different load intensities on circulating inflammatory biomarkers, body fat, muscular strength, and physical performance in postmenopausal women.

The primary purpose of this study was to identify the impact of whole-body resistance training (RT) at different load intensities on adipokines, adhesion molecules, and extracellular heat shock proteins in postmenopausal women. As secondary purpose, we analyzed the impact of RT at different load intensities on body fat, muscular strength, and physical performance. Forty participants were randomized into lower-load intensity RT (LIRT, n = 20, 30-35 repetition maximum in the first set of each exercise) or higher-load intensity RT (HIRT, n = 20, 8-12 repetition maximum in the first set of each exercise). Adipokines (adiponectin and leptin), adhesion molecules (MCP-1 and ICAM-1), extracellular heat shock proteins (HO-1 and eHSP60), body fat, muscular strength (1RM), and physical performance [400-meter walking test (400-M) and 6-minute walking test (6MWT)] were analyzed at baseline and after 12-weeks RT. There was a significant time-by-group interaction for eHSP60 (P = 0.049) and 400-M (P = 0.003), indicating superiority of HIRT (d = 0.47 and 0.55). However, both groups similarly improved adiponectin, ICAM-1, HO-1, body fat, 1RM, and 6MWT (P < 0.05). Our study suggests that load intensity does not seem to determine the RT effect on several obesity-related pro-inflammatory and chemotactic compounds, body fat, 1RM, and 6MWT in postmenopausal women, although a greater improvement has been revealed for eHSP60 and 400-M in HIRT. Novelty: Higher-load intensity resistance training improves eHSP60 and 400-M in postmenopausal women. Resistance training improves the inflammatory profile, body fat, muscle strength, and 6MWT, regardless of load intensity.

Influence of Adherence to Social Distancing Due to the COVID-19 Pandemic on Physical Activity Level in Post-bariatric Patients.

We assessed physical activity using accelerometers and a questionnaire in 33 post-bariatric patients who reported to be adherent (n = 15) or not (n = 18) to social distancing due to the COVID-19 pandemic. Patients adherent to social distancing spent more time in sedentary behavior (1.1 h/day, 0.1, 2.2; p = 0.045) and less time in moderate-to-vigorous physical activity (- 12.2 min/day, - 23.8, - 0.6; p = 0.040) vs. non-adherent ones. Bland-Altman analysis comparing objective and subjective physical activity estimates showed a bias for time spent in sedentary behavior and moderate-to-vigorous activity of 2.8 h/day and 8.5 min/day. In conclusion, post-bariatric patients who were adherent to social distancing measures were more inactive and sedentary than non-adherent ones. Strategies to increase physical activity in post-bariatric patients exposed to social distancing are necessary during the COVID-19 pandemic.

Atividade física no lazer como critério discriminante do menor nível de estresse percebido em adolescentes / Leisure-time physical activity as discriminant criterion of low level perceived stress in adolescents

O objetivo do presente estudo foi identificar os pontos de corte do tempo de realização de atividades físicas no lazer (AFL) de diferentes intensidades como critério discriminante do menor nível de estresse percebido (MEP) em adolescentes. Trata-se de um estudo transversal com amostra composta por adolescentes de 14 a 18 anos, de ambos os sexos, do ensino médio regular. Dados da atividade física e do MEP foram obtidos por meio de autorrelato, utilizando-se o questionário COMPAC. O MEP (respostas: "raramente" + "às vezes") foi considerado variável de classificação, enquanto minutos em AFL de intensidade moderada (AFLM), vigorosa (AFLV) e moderada a vigorosa (AFLMV) as variáveis de teste. Na análise dos dados foi usada a curva ROC, complementadas por valores de sensibilidade (SE) e especificidade (ES), adotando-se área sob a curva (AUC) > 0,50 e fixando-se p < 0,05. A amostra final deste estudo foi de 984 adolescentes (idade: homens = 15,93 ± 1,10 anos; moças = 15,87 ± 1,04 anos) com maior participação de moças (55,3%). O tempo de realização de AFLM ≥ 40 min/sem (AUC = 0,59; SE = 41,7%; ES = 75,7%; p < 0,002) e AFLMV ≥ 80 min/sem (AUC = 0,58; SE = 83,2%; ES = 36,2%; p < 0,04) para os rapazes apresentou poder discriminante para MEP. Neste estudo transversal, os minutos de realização de AFLM e AFLMV foram discriminantes do MEP para os rapazes. As AUC, para ambas as intensidades de AFL, foram baixas e com desequilíbrio entre valores de SE e ES. É sugerido que outros delineamentos de pesquisa sejam empregados a fim de estabelecer a relação causa e efeito entre a prática de AFL de diferentes intensidades e os níveis de estresse em adolescentes...(AU)

The aim of this study was to identify the cutoffs of the leisure-time physical activity (LPA), at different intensities, as discriminant criterion of lowest level of perceived stress (LLPS) in adolescents (14-18 years). This is a population-based, cross-sectional study, including regular high school students. PA and LLPS data was self-reported through questionnaire COMPAC. The classification variable was the LLPS (rarely + sometimes). The test variables were the minutes of LPAL of moderate intensity (LPAM) and vigorous (LPAV) and moderate to vigorous (LPAMV). The cutoffs were analyzed by ROC curves, complemented by sensitivity (SE) and specificity (ES) values, adopting area under the curve (AUC > 0.50; p < 0.05). The final sample of 984 adolescents (boys = 15.93 ± 1.10 years; girls = 15.87 ± 1.04 years) with a higher proportion of girls (55.3%). The time spent in LPAM ≥ 40 min/week (SE = 41.7%, ES = 75.7% AUC = 0.59; p < 0.002) and LPAMV ≥ 80 min/week (SE = 83.2%; ES = 36.2%; AUC = 0.58; p < 0.04) for the boys presented discriminant power to LLPS. In this cross-sectional study, LPAM and LPAMV minutes showed discriminatory power for LLPS in male. However, the AUCs for both LPA intensities were low and with imbalance between SE and ES values. Other research designs should be used to establish the cause-effect relationship between PAL and stress levels in adolescents...(AU)