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Summary: We aimed to provide evidence for an a priori hypothesis and sample size for subjectively assessing physical activity intensity and duration in paediatric population, adopting objective methods as the reference. We searched electronic databases, reference lists and author databases. Correlation coefficients were pooled as an indicator of agreement estimates. We found 183 agreement analyses (94.5% based on correlation coefficients) from 89 studies that met our inclusion criteria. We identified four physical activity parameters addressing intensity and two parameters addressing duration. The physical activity parameters focusing on intensity were measured only by questionnaires, and the best correlation was achieved by moderate‐to‐vigorous physical activity compared with a heart rate monitor. In addition, total physical activity duration had a stronger correlation with an accelerometer when measured by diaries or logs than when measured by questionnaires. In both cases, the correlation was moderate. Studies with sample sizes between 50 and 99 subjects showed measurements that were stable in both magnitude and interpretation. Our findings suggest that the agreement between subjective and objective methods for assessing physical activity intensity and duration is weak to moderate. Furthermore, sample sizes ranging from 50 to 99 subjects provide stable agreement estimates between methods. [ABSTRACT FROM AUTHOR]

Post-resistance exercise hypotension has been extensively described in men and women. However, gender influence on this response has not yet been clear. Gender might change post-exercise hemodynamics, since men and women respond differently during exercise. Thus, the purpose was to compare post-resistance exercise hypotension and its hemodynamic determinants in men and women. Normotensive subjects (22- male, 22-female) underwent 2 sessions: control (40 min of rest) and exercise (6 resistance exercises, 3 sets, 20 repetitions, at 40-50 % of 1RM). Blood pressure, heart rate, and cardiac output were measured prior to and following interventions. Blood pressure decrease after exercise was similar between the genders. However, hemodynamic determinants responded differently in men and women. Systemic vascular resistance reduced in women ( -4.6 ± 1.9U, P < 0.05), while cardiac output decreased in men ( -0.6 ± 0.2 L/ min, P < 0.05). This response was accompanied by a decrease in stroke volume in men ( -21.6 ± 5.1 ml, P < 0.05) and a more pronounced increase in heart rate in men than in women ( +11.3 ± 1.3 vs. +6.5 ± 1.7 bpm, P < 0.05, respectively). In conclusion, post-resistance exercise hypotension was similar in men and women. However, its hemodynamic determinants differ between the genders, depending on cardiac output decrease in men and on systemic vascular resistance decrease in women. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the effect of resistance training on resting blood pressure and heart rate variability in elderly postmenopausal women. 29 untrained, non-hypertensive elderly women were randomly assigned to 2 groups: an intervention group (n = 15, 65.5 ± 5.0 years, 57.3 ± 6.5 kg, 156.7 ± 5.1 cm) that underwent a supervised resistance training program (8 exercises, 2 sets, 10-15 repetitions, 3 times/ week) or a control group (n = 14, 66.2 ± 4.1 years, 61.1 ± 11.7 kg, 157.5 ± 7.1 cm) that participated in a supervised stretching program (25-30 min/session, 2 times/week). Resting auscultatory blood pressure, heart rate variability, evaluated from short recordings in a seated position, and maximal dynamic strength (1-RM test) were measured at baseline and after 12 weeks. A group x time ANOVA revealed that muscular strength increased significantly in the resistance training group (+ 10.2 % for bench press and + 12.7 % for leg extension, P < 0.05). Systolic blood pressure was reduced significantly in the resistance training group from pre- to post-intervention period (- 5 mmHg; P < 0.05), while no significant effect was noted for diastolic blood pressure and heart rate variability indexes ( P > 0.05). None of these variables changed in the control group throughout the study. In conclusion, a supervised resistance training program improved muscular strength and reduced systolic blood pressure without affecting diastolic blood pressure and heart rate variability in elderly postmenopausal women. [ABSTRACT FROM AUTHOR]

Moderate- to high-intensity strength training is recommended for healthy adults. In young subjects, a single session of strength training decreases blood pressure, while heart rate and cardiac work remain elevated afterwards. However, these effects have not been clearly demonstrated in elderly subjects. To investigate this issue, 16 elderly subjects each underwent a Control and an Exercise (3 sets, 8 RM, 9 exercises) session conducted in random order. Haemodynamic variables and heart rate variability were measured before and after the interventions. Systolic blood pressure did not change after the exercise session but did increase after the control session (+8.1 ± 1.6 mm Hg, P ≤ 0.05). Diastolic blood pressure, as well as systemic vascular resistance increased similarly after both sessions. Cardiac output and stroke volume decreased, while heart rate, rate-pressure product and the low- to high-frequency ratio of heart rate variability increased only after the exercise session ( − 0.5 ± 0.1 L/min, − 9.3 ± 2.0 ml, +3.8 ± 1.6 bpm, + 579.3 ± 164.1 mmHg.bpm and +0.71 ± 0.34, P ≤ 0.05). Ambulatory blood pressure was similar after both sessions, while heart rate and rate pressure product remained higher after the exercise session for up to 4.5 h. After a single session of strength training, cardiac sympathetic modulation and heart rate remain elevated in elderly subjects, keeping cardiac work elevated for a long period of time. [ABSTRACT FROM AUTHOR]

Rafael Gauche,1 Ricardo M Lima,1,2 Jonathan Myers,2 André B Gadelha,1 Silvia GR Neri,1 Claudia LM Forjaz,3 Lauro C Vianna1 1Faculty of Physical Education, University of Brasília, Brasília, Brazil; 2Cardiology Division, Veterans Affairs Palo Alto Health Care System and Stanford University, Palo Alto, CA, USA; 3School of Physical Education and Sport, University of São Paulo, São Paulo, Brazil Purpose: This study aimed to investigate the effects of resistance exercise (RE) on autonomic control and blood pressure (BP) reactivity during mental stress (MS) in treated older hypertensive women. Methods: Ten older hypertensive women (age =71.1±5.5 years; body mass index =24.2±3.9; mean BP [MBP] =85.4±3.5) underwent a protocol consisting of BP and heart rate variability (HRV) output assessments at baseline and during MS, and these measurements were taken before and 60 minutes after two bouts of RE (traditional and circuit). MS was induced through a computerized 3-minute Stroop color–word test before and 1 hour after each exercise session; BP was measured every minute during MS, and HRV was monitored as a measure of cardiac autonomic control. Results: A significant effect of time on systolic BP (∆pre =17.4±12.8 versus ∆post =12.5±9.6; P=0.01), diastolic BP (∆pre =13.7±7.1 versus ∆post =8.8±4.5; P=0.01), and MBP (∆pre =14.0±7.7 versus ∆post =9.3±5.4; P

We aimed to provide evidence for an a priori hypothesis and sample size for subjectively assessing physical activity intensity and duration in paediatric population, adopting objective methods as the reference. We searched electronic databases, reference lists and author databases. Correlation coefficients were pooled as an indicator of agreement estimates. We found 183 agreement analyses (94.5% based on correlation coefficients) from 89 studies that met our inclusion criteria. We identified four physical activity parameters addressing intensity and two parameters addressing duration. The physical activity parameters focusing on intensity were measured only by questionnaires, and the best correlation was achieved by moderate-to-vigorous physical activity compared with a heart rate monitor. In addition, total physical activity duration had a stronger correlation with an accelerometer when measured by diaries or logs than when measured by questionnaires. In both cases, the correlation was moderate. Studies with sample sizes between 50 and 99 subjects showed measurements that were stable in both magnitude and interpretation. Our findings suggest that the agreement between subjective and objective methods for assessing physical activity intensity and duration is weak to moderate. Furthermore, sample sizes ranging from 50 to 99 subjects provide stable agreement estimates between methods., (© 2018 World Obesity Federation.)