Patterns of sedentary behavior in adults: A cross-sectional study.

Introduction: Sedentary behavior (SB) has been associated with adverse health outcomes, however, it is not completely clear whether total time in SB during the day or prolonged uninterrupted SB are interrelated. The aim of the current study was to describe the different patterns of SB of adults, their relationships, and associated factors. Methods: The sample included 184 adults aged ranging from 18 to 59 years old. SB was objectively measured by an accelerometer and the following SB pattern parameters were obtained: total time in sedentary bouts, mean time of sedentary bouts, and total time in sedentary breaks. Demographic data (age and sex), anthropometry [weight, height, body mass index (BMI)], blood pressure (BP), medical history (self-reported comorbid conditions), and cardiac autonomic modulation, were assessed to identify factors associated with SB. Multiple linear regressions were used to analyze the relationship between SB parameters and the associated factors. Results: The parameters of SB indicated 2.4 (0.9) h/day for total time in sedentary bouts, 36.4 (7.9) min for the mean time of sedentary bouts, and 9.1 (1.9) h/day for the total time in sedentary breaks. Multiple adjusted regression indicated that age was the only factor associated with SB patterns (p < 0.05) after adjustment for confounding variables (sex, age, BMI, dyslipidemia, systolic and diastolic BP). Young adults (18-39 years old) spent more time in sedentary bouts and less time in uninterrupted sedentary bouts compared to middle-aged adults (40-59 years old) (2.58 (0.88) h/day vs. 2.13 (0.90) h/day, respectively; p = 0.001 and 34.5 (5.8) min 18-39 years old vs. 38.8 (9.6) min 40-59 years old; p ≤ 0.001; respectively). The total time in sedentary breaks was similar between age groups (p = 0.465). The total time in sedentary bouts was significantly correlated with the mean time of sedentary bouts (r = -0.58; p ≤ 0.001), and with the total time in sedentary breaks (r = -0.20; p = 0.006). The mean time of sedentary bouts was significantly related to the total time in sedentary breaks (r -= 0.19; p = 0.007). Discussion and Conclusion: In conclusion, age seems to be a relevant factor associated with sedentary behavior with young adults spending more time in SB and accumulating this behavior in a higher amount of sedentary bouts compared to middle-aged adults.

Acute effect of bodyweight-based strength training on blood pressure of hypertensive older adults: A randomized crossover clinical trial.

Background: Strength Training (ST) reduces the cardiovascular risk of hypertensive elderly people; however, there is a need for efficient and low-cost ST programs that aim to reduce blood pressure (BP) in elderly people with adherence and affectivity in this population. Objective: Evaluate the acute effect on BP and satisfaction with the practice of bodyweight-based strength training (BWST) in hypertensive older adults. Methods: Participants performed a BWST session and a control session (CS). The BWST consisted of six exercises, with three sets of 30 seconds. In the CS, no activity was performed. BP was measured before and at 0, 10, 20, and 30 minutes post-session. Participants' satisfaction was assessed. Results: Eleven older adults (65.8 ± 4.6 years; 7 men) participated in the study. There was an increase (p = .028) in systolic BP immediately after BWST, returning to baseline values in the intervals 10, 20, and 30 post-section. In the CS there was an increase (p = .009) 30 minutes post-session compared to 20 minutes. Between sessions, a lower systolic BP was found in BWST (-6.54 ± 3.31; p = .048) 30 minutes post-sessions. For satisfaction, 82% of participants were "totally satisfied" with BWST. Conclusion: The SBP is lower 30 minutes after BWST session than control session, and BWST promoted a pleasant affective response in hypertensive older adults.

Effects of Different Weekly Sets-Equated Resistance Training Frequencies on Muscular Strength, Muscle Mass, and Body Fat in Older Women.

Pina, FLC, Nunes, JP, Schoenfeld, BJ, Nascimento, MA, Gerage, AM, Januário, RSB, Carneiro, NH, Cyrino, ES, and Oliveira, AR. Effects of different weekly sets-equated resistance training frequencies on muscular strength, muscle mass and body fat in older women. J Strength Cond Res 34(10): 2990-2995, 2020-The aim of this study was to analyze the effects of different resistance training (RT) frequencies (2 vs. 3 times per week) with an equivalent number of weekly sets performed between conditions on muscular strength and body composition in older women. Forty-seven older women (65 ± 4 years) were divided into 2 groups that performed a 12-week RT program either 2 (G2x and 3 sets) or 3 (G3x and 2 sets) times per week. The groups were evaluated before and after study on measures of body composition through dual-energy x-ray absorptiometry, and muscular strength through one repetition maximum (1RM) testing. Lean soft tissue was significantly increased in both groups (G2x = +1.7%, G3x = +1.7%), while only G3x reduced body fat after the intervention period (G2x = -0.7%, G3x = -2.9%). Similarly, significant increases were noted between conditions for 1RM scores in bench press (G2x = +11.8%, G3x = +11.9%) and knee extension (G2x = +17.4%, G3x = +10.8%). The results indicate that performing 2 or 3 RT sessions per week promotes similar improvements in muscular outcomes, while training more frequently may reduce body fat after 12 weeks of weekly sets-equated RT in untrained older women.

Agreement Between Bioelectrical Impedance and Dual-Energy X-Ray Absorptiometry to Track Changes in Fat-Free Mass After Resistance Training in Older Women.

Nascimento, MA, Silva, DRP, Ribeiro, AS, Pina, FLC, Gerage, AM, Gobbo, LA, Mayhew, JL, and Cyrino, ES. Agreement between bioelectrical impedance and dual-energy x-ray absorptiometry to track changes in fat-free mass after resistance training in older women. J Strength Cond Res 34(6): 1700-1708, 2020-The aim of our study was to compare the agreement between bioelectrical impedance (BIA) and dual-energy X-ray absorptiometry (DXA) to track changes on fat-free mass (FFM) after a resistance training (RT) program in older women. Forty-three older women (65.2 ± 4.6 years, 59.5 ± 9.2 kg, 156.4 ± 6.0 cm, 24.3 ± 3.3 kg·m) participated in a RT intervention (12 weeks, 8 exercises, 2 sets, 10-15 repetitions, 3 nonconsecutive days per week). Fat-free mass changes were determined by a single-frequency BIA device (EQ1), 6 BIA prediction equations for older women (EQ2, EQ3, EQ4, EQ5, EQ6, and EQ7), and DXA. At pretraining, 3 equations overpredicted, and 3 underpredicted DXA FFM (F = 244.63, p < 0.001), although all equations had high correlations with DXA (r = 0.78-0.83). After training, 4 equations overpredicted and one underpredicted DXA FFM (F = 176.25, p < 0.001). Dual-energy X-ray absorptiometry detected significant gains in FFM (0.65 ± 0.82 kg; p < 0.05), as did EQ3 (0.55 ± 1.69 kg; p < 0.05), and EQ4 (0.61 ± 1.88 kg; p < 0.05), whereas the remaining equations did not indicate significant changes in FFM. Low correlations between FFM and equation change values suggest that single-frequency BIA-derived equations may not provide sufficient accuracy to track changes in FFM after 12 weeks of RT in older women.

Does leisure-time physical activity attenuate or eliminate the positive association between obesity and high blood pressure?

We examine the joint association of weight status and leisure-time physical activity on high blood pressure in a nationally representative sample of adults and older adults in Brazil. This was a national cross-sectional survey conducted in Brazil in 2013 (Brazilian Health Survey). The sample consisted of 59 402 participants (56% women, aged 18 to 100 years). Outcome was objectively assessed blood pressure. Body mass index (BMI) was objectively measured, while self-reported information on leisure-time physical activity, TV viewing, chronological age, race, educational status, tobacco smoking, sodium consumption, and hypertension medication was obtained using questionnaires. Logistic regression analysis with adjusted odds ratio was conducted to test the joint association of BMI and leisure-time physical activity categories on high blood pressure. Overall, compared to normal weight (NW) and physically active group, the NW/inactive (OR = 1.28; 1.04 to 1.58), overweight/active (OR = 1.38; 1.08 to 1.78), overweight/inactive (OR = 1.89; 1.53 to 2.33), obese/active (OR = 2.19; 1.59 to 3.01) and obese/inactive (OR = 2.54; 2.05 to 3.15) groups were 28% to 254% more likely to have high blood pressure. The attenuation and high blood pressure was greater for women and adults than for men and older adults. Thus, leisure-time physical inactivity and being overweight and obesity were associated with high blood pressure in Brazilian population. Engaging in sufficient level of physical activity during leisure could attenuate, but not eliminate, the negative influence of obesity on high blood pressure in Brazilian adults and older adults.

Association between physical activity and walking capacity with cognitive function in peripheral artery disease patients.

OBJECTIVE: To identify the association between objectively measured physical activity and walking capacity with cognitive function in patients with symptomatic peripheral artery disease. METHODS: This was an observational, cross sectional study. One hundred and thirty patients (age 67 ± 8 years) were recruited at a tertiary centre specializing in vascular disease. Cognitive function (global, memory, executive function and attention) was evaluated using the Montreal Cognitive Assessment tool. Physical activity levels (total, light, and moderate-vigorous) were obtained using an accelerometer. A 6 min and 4 m walk test were undertaken to assess walking capacity. Crude and covariate adjusted, linear regression analyses confirmed significant associations between physical activity levels and walking capacity with cognitive function. RESULTS: Positive and significant associations were observed between moderate to vigorous physical activity (p = .039) and walking capacity (p = .030) with memory after adjusting for covariates. No significant association was identified between light physical activity and usual gait speed with any cognitive function outcome. CONCLUSION: Greater memory performance was associated with greater moderate to vigorous physical activity levels and walking capacity in patients with symptomatic peripheral artery disease. Clinical interventions focused on improving moderate to vigorous physical activity levels and walking capacity may provide important therapies to potentially enhance cognitive health in patients with peripheral artery disease.

Resistance training with dietary intake maintenance increases strength without altering body composition in older women.

BACKGROUND: Evidence suggests that the aging process tends to lead to sarcopenia and osteoporosis which reduce the quality of life in older women. Resistance training (RT) is widely supported as a means of delaying or offsetting the decline in muscle strength and loss of bone mineral content in older women. The purpose of this investigation was to analyze the effects of a 12-wk RT program (3 times a week) with dietary intake maintenance on muscle strength and body composition of healthy, sedentary older women. METHODS: Forty-four older women were randomly assigned to a RT program (N.=22, 66.3±4.8 years, 60.7±9.1 kg, 153.1±0.90 cm, 24.9±3.3 kg/m²) or a control group (N.=22, 66.4±4.0 years, 63.3±7.5 kg, 155.5±5.8 cm, 26.2±2.6 kg/m²) performing stretching exercises during the same period. One-repetition maximum test on chest press and leg extension were used to assess muscle strength. Body composition was measured by dual energy x-ray absorptiometry to determine fat mass, fat-free mass, and bone mineral content. Dietary intake was recorded using a 3-day food records. All subjects maintained their normal diet during the investigation. RESULTS: No significant differences were found for the body composition components within and between groups. A significant time by group interaction indicated that the RT group made greater improvements in upper and lower limb muscle strength (chest press ~12%, P=0.0001; leg extension ~13%, P<0.0001). CONCLUSIONS: These results suggest that RT program improves muscle strength of major muscle groups, without altering body composition in older women under dietary intake maintenance.

Twenty minutes of post-exercise hypotension are enough to predict chronic blood pressure reduction induced by resistance training in older women

AIM: This study investigated the correlation between post-exercise hypotension (PEH) and chronic blood pressure (BP) reduction in older women after a resistance training (RT) program. METHODS: Twenty-five older women (≥60 years) performed a RT program for 8 weeks, 3x/week consisting of 3 sets of 8-12 repetitions maximum in 8 exercises. Acute and chronic BP measurements were performed using automatic equipment, in which acute BP was measured before and after 10, 20, 30, 40, 50 and 60 min following the sixth exercise session, while chronic BP was measured pre and post-training. RESULTS: Significant decrease for systolic blood pressure (SBP) was observed after the intervention period, however, the diastolic blood pressure (DBP) did not change. To acute changes in BP, SBP decreased at all times after a single RT session, while DBP increased after 40 min. The reduction for SBP after a single RT session at baseline showed positive and significant correlations with the reductions in basal SBP observed after the 8 weeks of RT, the strongest correlations were observed at 20 min. A linear relationship between the magnitude of change in chronic SBP and the 20 min for acute SBP, and 30 min for acute DBP of post-exercise was observed. CONCLUSION: The results suggest that acute BP lowering after RT session is a reliable predictor of chronic BP response to exercise training, and 20 min of resting, after RT training, is enough to indicate chronic response of BP as this measure was highly associated with chronic BP lowering in older women.(AU)

Sedentary Behavior and Light Physical Activity Are Associated with Brachial and Central Blood Pressure in Hypertensive Patients.

BACKGROUND: Physical activity is recommended as a part of a comprehensive lifestyle approach in the treatment of hypertension, but there is a lack of data about the relationship between different intensities of physical activity and cardiovascular parameters in hypertensive patients. The purpose of this study was to investigate the association between the time spent in physical activities of different intensities and blood pressure levels, arterial stiffness and autonomic modulation in hypertensive patients. METHODS: In this cross-sectional study, 87 hypertensive patients (57.5 ± 9.9 years of age) had their physical activity assessed over a 7 day period using an accelerometer and the time spent in sedentary activities, light physical activities, moderate physical activities and moderate-to-vigorous physical activities was obtained. The primary outcomes were brachial and central blood pressure. Arterial stiffness parameters (augmentation index and pulse wave velocity) and cardiac autonomic modulation (sympathetic and parasympathetic modulation in the heart) were also obtained as secondary outcomes. RESULTS: Sedentary activities and light physical activities were positively and inversely associated, respectively, with brachial systolic (r = 0.56; P < 0.01), central systolic (r = 0.51; P < 0.05), brachial diastolic (r = 0.45; P < 0.01) and central diastolic (r = 0.42; P < 0.05) blood pressures, after adjustment for sex, age, trunk fat, number of antihypertensive drugs, accelerometer wear time and moderate-to-vigorous physical activities. Arterial stiffness parameters and cardiac autonomic modulation were not associated with the time spent in sedentary activities and in light physical activities (P > 0.05). CONCLUSION: Lower time spent in sedentary activities and higher time spent in light physical activities are associated with lower blood pressure, without affecting arterial stiffness and cardiac autonomic modulation in hypertensive patients.

Physical activity and prevalence of hypertension in a population-based sample of Brazilian adults and elderly.

OBJECTIVES: a) To determine the prevalence of hypertension and its associated factors and b) to establish the impact of past (i.e. adolescence) and current physical activity on hypertension. METHODS: A cross-sectional study of people aged 40 years or more living in the urban area of Pelotas - Brazil (2003). Hypertension was assessed by self-report of medical diagnosis. Individuals were considered active in adolescence if they reported regular physical activity practice between the ages 10 and 19 years. In adulthood, individuals who performed > or =150 min/week of leisure-time physical activities were considered active. Other variables studied included skin color, age, smoking, body mass index and socioeconomic status. RESULTS: 1696 individuals were interviewed (response rate >95%). Prevalence of hypertension was 34.4% (CI(95%) 32.1-36.7) and varied considerably among population subgroups. Current physical activity showed no association with hypertension. Physical activity in adolescence was associated with a decreased risk of adulthood hypertension in the crude analyses for women (p<0.001). However, after adjusting for potential confounders and mediators, this protection was no longer significant 1.20 (CI(95%) 0.93-1.55). CONCLUSIONS: Prevalence of hypertension is high among Brazilians and markedly different among population subgroups. There was no robust evidence of association between adolescence physical activity practice and hypertension in later life.