Acute Effects of Breaking up Sitting Time With Isometric Wall Squat Exercise on Vascular Function and Blood Pressure in Sedentary Adults: Randomized Crossover Trial.

PURPOSE: The World Health Organization has recommended breaking up sitting time to improve cardiovascular health. However, whether isometric exercise can be effectively used as a strategy to break up sitting time remains unclear. Thus, the aim of this study was to analyze the acute effects of breaking up prolonged sitting with isometric wall squat exercise (IWSE) on vascular function and blood pressure (BP) in sedentary adults. METHODS: This randomized crossover trial included 17 adults (53% male, 26 ± 6 yr, 22.4 ± 3.6 kg/m2) with high sedentary behavior (≥ 6 hr/d). The participants completed 2 experimental sessions in a randomized order, both sharing a common sitting period of 180 min: Breaks (2-min breaks were incorporated into the IWSE, with participants maintaining their knees at the angle determined by the incremental test, which occurred every 30 min) and Control (sitting for 180 min continuously). Popliteal artery flow-mediated dilation (FMD) and brachial BP were measured before and at 10 and 30 min after the experimental sessions. RESULTS: The results did not indicate significant session vs time interaction effects on popliteal FMD and brachial BP (P > .05). A subanalysis including only participants with popliteal FMD reduction after the Control session (n = 11) revealed that Breaks enhanced popliteal FMD after 10 min (1.38 ± 6.45% vs -4.87 ± 2.95%, P= .002) and 30 min (-0.43 ± 2.48% vs -2.11 ± 5.22%, P= .047). CONCLUSION: Breaking up prolonged sitting with IWSE mitigates impaired vascular function resulting from prolonged sitting but has no effect on BP in sedentary adults.

Clustering of 24H movement behaviors associated with clinic blood pressure in older adults: a cross-sectional study.

Physical activity (PA), sedentary behavior (SB), and sleep duration are known to have an individual effect on clinic blood pressure (BP) of older adults. However, whether different patterns of these so-called movement behaviors over the 24h-cycle on BP remains poorly investigated. The study aimed to identify movement behavior patterns associated with clinic BP among older adults with chronic diseases. Cross-sectional study with 238 older adults (80.3% female; mean age 68.8 ± 6.6) with at least one chronic disease. PA, SB, and sleep duration were measured by a triaxial accelerometer. Clinic systolic BP (SBP) and diastolic BP (DBP) were obtained through an automated method following standard procedures. Non-hierarchical K-means cluster and linear regression modeling were employed to identify the clusters of movement behaviors and to examine the associations. Two clusters were identified [active and non-sedentary, n = 103 (i.e., sufficient sleep duration, higher LPA and MVPA, and lower SB) and sedentary and inactive, n = 135 (i.e., sufficient sleep duration, lower LPA and MVPA, and higher SB). Active and non-sedentary older adults presented lower systolic BP compared to sedentary and inactive ones, even after adjustments for sociodemographic and clinical characteristics (ß = 6.356; CI 95% from 0.932 to 11.779; P = 0.022). No associations were found for diastolic BP. In conclusion, higher PA and lower SB were associated with lower systolic BP in older adults with chronic diseases. However, sleep duration did not modify this association. Therefore, interventions focusing on concomitantly increasing PA levels and reducing SB should be the priority for controlling blood pressure.

Characteristics associated with responsiveness to isometric handgrip training in medicated hypertensive patients: secondary data analysis.

OBJECTIVE: Isometric handgrip training (IHT) has been shown to reduce blood pressure (BP) in hypertensive patients. However, factors that predict responsiveness to IHT are largely unknown. The aim of this study was to investigate the patient characteristics associated with the antihypertensive response to IHT using a recommended statistical approach for evaluating interindividual responses. METHODS: Data from four randomized controlled trials were combined, totaling 81 patients undergoing IHT (48.8% women; 60 ±â€Š11 years) and 90 control patients (45.6% women; 62 ±â€Š12 years). IHT consisted of 4 × 2 min isometric contractions at 30% of maximal voluntary contraction, performed three times/week for 8-12 weeks. BP was measured at baseline and following IHT and control interventions. The interindividual variation was assessed by the standard deviation of the individual responses (SD ir ), and linear regression analyses were conducted to explore response predictors. RESULTS: IHT significantly decreased both SBP (-5.4; 95% confidence interval (CI) -9.5 to -1.3 mmHg) and DBP (-2.8; 95% CI -5.1 to -0.6 mmHg). The interindividual variation of BP change was moderate for systolic (SD ir  = 5.2 mmHg, 0.30 standardized units) and low for diastolic (SD ir  = 1.7 mmHg, 0.15 standardized units). Sex, age, and BMI were not associated with the antihypertensive effect of IHT. However, a higher baseline SBP ( b  = -0.467, P  < 0.001) and absence of dihydropyridine calcium channel blockers use ( b  = 0.340, P  = 0.001) were associated with greater BP reductions. CONCLUSION: IHT reduced BP in medicated hypertensive patients regardless of age, sex, and BMI. Patients with a higher baseline SBP and those not prescribed dihydropyridine calcium channel blockers were more responsive to IHT.

Isometric Exercise Training and Arterial Hypertension: An Updated Review.

Hypertension is recognised as a leading attributable risk factor for cardiovascular disease and premature mortality. Global initiatives towards the prevention and treatment of arterial hypertension are centred around non-pharmacological lifestyle modification. Exercise recommendations differ between professional and scientific organisations, but are generally unanimous on the primary role of traditional aerobic and dynamic resistance exercise. In recent years, isometric exercise training (IET) has emerged as an effective novel exercise intervention with consistent evidence of reductions in blood pressure (BP) superior to that reported from traditional guideline-recommended exercise modes. Despite a wealth of emerging new data and endorsement by select governing bodies, IET remains underutilised and is not widely prescribed in clinical practice. This expert-informed review critically examines the role of IET as a potential adjuvant tool in the future clinical management of BP. We explore the efficacy, prescription protocols, evidence quality and certainty, acute cardiovascular stimulus, and physiological mechanisms underpinning its anti-hypertensive effects. We end the review with take-home suggestions regarding the direction of future IET research.

Association of Early Sports Practice with Cardiovascular Risk Factors in Community-Dwelling Adults: A Retrospective Epidemiological Study.

BACKGROUND: Sports practice in childhood and adolescence has been inversely related to the chances of developing cardiovascular risk factors (CRFs). However, it is not clear whether sports practice in childhood and adolescence could be inversely related to CRF in adult life. OBJECTIVES: This study aimed to analyze the association between early sports practice and cardiovascular risk factors in a randomized sample of community-dwelling adults. METHODS: For this, 265 adults aged ≥ 18 years composed the sample. Cardiovascular risk factors of obesity, central obesity, diabetes, dyslipidemia, and hypertension were collected. Early sports practice was retrospectively self-reported using an appropriate instrument. Total physical activity level was assessed by accelerometry. The association between early sports practice and cardiovascular risk factors in adulthood was analyzed by binary logistic regression, adjusted for sex, age, socioeconomic status, and moderate-to-vigorous physical activity. RESULTS: Early sports practice was observed in 56.2% of the sample. The prevalence of central obesity (31.5 vs. 50.0%; p = 0.003), diabetes (4.7% vs. 13.7%; p = 0.014), dyslipidemia (10.7% vs. 24.1%; p = 0.005), and hypertension (14.1% vs. 34.5%; p = 0.001) was lower in participants who reported early sports practice. Participants who reported early sports practice in childhood and adolescence were, respectively, 60% (OR = 0.40; 95% CI 0.19-0.82) and 59% (OR = 0.41; 95% CI 0.21-0.82) less likely to have hypertension in adult life when compared to those with no early sports practice, independently of sex, age, socioeconomic status, and habitual physical activity level in adulthood. CONCLUSION: Early sports practice in childhood and adolescence was a protective factor for hypertension in adulthood.

Effects of resistance training on endothelial function: A systematic review and meta-analysis.

BACKGROUND AND AIMS: The effects of resistance training on flow-mediated dilation (FMD), which has been the gold standard non-invasive assessment of endothelial function and is associated with the risk of cardiovascular events, are not well known. We conducted a systematic review to analyze the effects of resistance training on FMD. METHODS: We searched Pubmed, Embase, CINAHL, SPORTDiscuss, Scopus, Web of Science and PEDro databases for studies that met the following criteria: (a) randomized controlled trials of resistance exercise with a comparative non-exercise group or contralateral untrained limb in adults and/or elderly; (b) studies that measured post-occlusion brachial artery FMD by ultrasonography, before and after intervention. Mean differences (MDs) with 95 % confidence interval (95 % CI) were calculated using an inverse variance method with a random effects model. RESULTS: Twenty-three studies were included in the meta-analysis (n = 785 participants; 53 % females). Resistance training on FMD responses showed a favorable result for the resistance training group (n = 366) compared to the control group (n = 358) (MD 2.39, 95%CI 1.65, 3.14; p<0.00001). Subgroup analysis indicated favorable results for the dynamic resistance training (n = 545; MD 2.12, 95 % CI 1.26, 2.98; p<0.00001) and isometric handgrip training (n = 179; MD 3.32, 95 % CI 1.68, 4.96; p<0.0001) compared to the control group. The effect of resistance training on FMD responses was also favorable regardless of the condition of the participants (Healthy [n = 261]: MD 2.11, 95 % CI 1.04, 3.18; p<0.0001; Cardiovascular disease [n = 310]: MD 2.89, 95 % CI 0.88, 4.90; p = 0.005; metabolic disease [n = 153]: MD 2.40, 95 % CI 1.59, 3.21; p<0.00001). CONCLUSIONS: Resistance training improves FMD in healthy individuals and patients with cardiovascular and metabolic diseases.

Acute effects of breaking up sitting time with isometric exercise on cardiovascular health: Randomized crossover trial.

The objective of this study was to analyze the acute effects of breaking up prolonged sitting with isometric exercise on the cardiovascular health of sedentary adults. This is a three-condition randomized crossover trial. The sample was comprised of 17 subjects (11 women; 29 ± 10 years old; 25,1 ± 5,1 kg/m2 ). The participants completed, in randomized order, three experimental conditions (control, breaks with isometric leg extension exercise, and breaks with walking), with the order of the conditions determined through simple automatic randomization. All the conditions had in common a sitting period of 3 h. During the conditions with isometric exercise and walking breaks the participants performed breaks with isometric leg extension exercise and with walking every 30 min, while in the control condition they remained seated with no breaks. Before and after this period, vascular function (primary outcome), blood pressure, and cardiac autonomic modulation (secondary outcomes) were measured. Generalized estimated equations were used to analyze the data. The results did not indicate significant interaction effects for vascular function among experimental conditions (p > 0,05 for all). We also did not find significant interaction effects for systolic or diastolic blood pressure among the conditions (p > 0,05 for all). The heart rate variability parameters did not present significant interaction effects among conditions (p > 0,05 for all). In conclusion, breaking up sitting with isometric exercise does not seem to lead to significant effects on the cardiovascular health of sedentary adults.

Relationship of Cardiac Autonomic Modulation with Cardiovascular Parameters in Adults, According to Body Mass Index and Physical Activity.

This study aimed to analyze the relationship between cardiac autonomic modulation (CAM) and cardiovascular parameters (blood pressure and resting heart rate) in a sample of 256 adults, grouped by body mass index and sufficient moderate-to-vigorous physical activity (≥150 min/week). The sample showed different cardiovascular parameters and CAM according to body mass index, but not according to physical activity. Adults who are overweight and physically active presented higher relationship between CAM and blood pressure than those who are insufficiently active, similarly to normal weight groups. Recommended levels of physical activity may play an important role in the relationship of HRV with cardiovascular parameters in overweight adults, regardless of sex, age, socioeconomic level, and central fat. Trial registration: Registered at ClinicalTrials.gov (NCT03986879). Graphical abstract.

The same storm but not the same boat: Effects of COVID-19 stay-at-home order on mental health in individuals with overweight.

OBJECTIVE: To describe the effects of stay-at-home orders and social distancing during the coronavirus disease (COVID-19) outbreak on mental health and to compare these outcomes between individuals with normal weight and overweight. METHODS: This cross-sectional study included 1857 Brazilian adults, who were invited through social media to answer an online questionnaire from 5 May 2020 to 17 May 2020. The instrument included questions related to health behaviour, mental health (anxiety, depression, self-esteem, sadness and stress) and overall health. Overweight was defined as body mass index (BMI) ≥ 25 Kg/m2 . Multiple logistic regression was conducted to identify whether overweight is associated with mental health variables. RESULTS: Women reported increased anxiety (36.5% vs 22.2%, P < .01), depression (16.2% vs 8.8%, P < .01), low self-esteem (19.8% vs 10.6%, P < .01), sadness (17.7% vs 10.2%, P < .01), and stress (29.5% vs 19.3%, P < .01) relative to men. Women with overweight are more likely to report higher feeling of anxiety (OR 1.62, CI 95% 1.22-2.14), depression (OR 1.79, CI 95% 1.25-2.55), low self-esteem (OR 1.82, CI95% 1.28-2.58) and sadness (OR 1.51, CI 95% 1.08-2.10), adjusted for age, social isolation days, educational level, chronic diseases, smoke, alcohol intake and physical activity. CONCLUSION: Women, specially those with overweight are more vulnerable to the deleterious effects of stay-at-home orders on mental health during the COVID-19 pandemic.

Relationship between domains of physical activity and cardiac autonomic modulation in adults: a cross-sectional study.

This study aimed to analyze the relationship of physical activity in different domains with cardiac autonomic modulation in adults. A sample of 252 adults was randomly selected, with mean age of 42.1 (± 16.5) years, being 58% of women. Cardiac autonomic modulation was assessed through indexes of heart rate variability in time (SDNN, RMSSD) and frequency (LF, HF) domains for linear method, and by Poincaré plot for non-linear method (SD1, SD2 components). Domains of PA (occupation, sport, leisure time/commuting, and total) were assessed by Baecke's questionnaire. Variables of age, gender, socioeconomic status (questionnaire) and body mass index (objectively measures) were covariates. Occupational PA was positively related to LF (ß = 2.39, 95% CI 0.24; 4.54), sports PA was positively related to SDNN (ß = 3.26, 95% CI 0.18; 7.05), RMSSD (ß = 4.07, 95% CI 0.31; 7.85), and SD1 (ß = 2.85, 95% CI 0.11; 5.81), and leisure time/commuting PA was positively related to SDNN (ß = 3.36, 95% CI 0.28; 6.70) and RMSSD (ß = 3.53, 95% CI 0.46; 7.52) indexes. Total PA was related to RMSSD (ß = 1.70, 95% CI 0.04; 3.72). Sports, leisure time/commuting, and total PA were related to higher parasympathetic modulation, while occupational PA was related to higher sympathetic modulation to the heart in adults.

Acute effects of the intensity in the agonistantagonist paired-set on the neuromuscular performance / Efeito agudo da intensidade no sistema agonista-antagonista pareado por série sobre o desempenho neuromuscular

The intensity employed in the agonist-antagonist paired-set (AAPS) system may influence neuromuscular performance due to increased fatigue and decreased antagonist coactivation. However, it is not yet known whether performing submaximal repetitions at different intensities (i.e., wit h out m uscle failure) negatively affects agonist muscle performance. The aim of this study was to verify the acute effect of the AAPSsystem performed at different intensities with submaximal repetitions. 20 trained m ales in resistance training (RT) (21.8 [3.1] years; 76.9 [9.7] kg; 1.7 [0.0] m; 24.3 [2.6] kg/m2 ) participated of this investigation. All the participants were allocated in a randomized order in one of the two AAPS configurations: high-load (HL) or low-load (LL). In the HL condition, the individuals were submit t ed to one set of eight repetitions at 75% of one-repetition maximum (1RM) in the knee flexion (i.e., antagonist), followed by 75% 1RM knee extension (i.e., agonist) exercise until momentary concentric failure. In t he LL condition, they performed one set of 12 repetitions at 50% 1RMin the knee flexion, followed by knee extension at 75%1RM also until momentary concentric failure. Both experimental conditions p resented similar values for the number of repetitions, without significant difference (p= 0.66, ES= 0.15). Thus, our data suggest that the adoption of AAPS system without an increase of the antagonist fatigue and consequently no reduction of coactivation, acutely, may not lead to increased p erfo rm an ce o f target musculature during a resistance exercise session...(AU)

A intensidade empregada no sistema agonista-antagonista pareado por série ( AAPS) pode influenciar o desempenho neuromuscular devido ao aumento da fadiga e diminuição da co ativação do antagonista. No entanto, ainda não se sabe se realizar repetições submáximas em diferentes intensidades (i.e., sem falha muscular) afeta negativamente o desempenho muscular. O objetivo deste estudo foi verificar o efeito agudo do sistema AAPS realizado em diferentes intensidades com repetições submáximas. 20 homens treinados em treinamento resistido (TR) (21.8 ± 3.1 anos; 76.9 ± 9.7 kg; 1.7 ± 0.0 m; 24.3 ± 2.6 kg/m2 ) participaram desta investigação. Todos os participantes foram alocados, de forma aleatória, em uma das duas configurações do sistema AAPS: alta-carga (AC) ou baixa- carga (BC). Na condição AC, os indivíduos foram submetidos a uma série de oito repetições a 75% 1RMno exercício de flexão do joelho (i.e., antagonista), seguido por uma série a 75% 1RM de extensão do joelho até a falha oncêntrica momentânea. Ambas as condições experimentais apresentaram v alores sim ilares para o número de repetições, sem diferença significante (p = 0.66, TE = 0.15). Assim, nossos dados sugerem que a adoção do sistema AAPSsem aumento da fadiga do antagonista e consequentemente sem redução da coativação, agudamente, pode não levar ao aumento do desempenho da musculatura alvo durante uma sessão de exercício resistido...(AU)

Effects of Isometric Handgrip Training in Patients With Peripheral Artery Disease: A Randomized Controlled Trial.

Background Meta-analyses have shown that isometric handgrip training (IHT) can reduce brachial systolic and diastolic blood pressure (BP) by >6/4 mm Hg, respectively. However, whether IHT promotes these effects among patients with peripheral artery disease, who exhibit severe impairment in cardiovascular function, is currently unknown. This study aimed to evaluate the effects of IHT on the cardiovascular function of patients with peripheral artery disease. Methods and Results A randomized controlled trial with peripheral artery disease patients assigned to either the IHT or control group was conducted. The IHT group performed 3 sessions per week, for 8 weeks, of unilateral handgrip exercises, consisting of 4 sets of isometric contractions for 2 minutes at 30% of maximum voluntary contraction and a 4-minute interval between sets. The control group received a compression ball in order to minimize the placebo effects, representing sham training. The primary outcome was brachial BP. The secondary outcomes were central BP, arterial stiffness parameters, cardiac autonomic modulation, and vascular function. The IHT program reduced diastolic BP (75 [10] mm Hg preintervention versus 72 [11] mm Hg postintervention), with no change in the control group (74 [11] mm Hg preintervention versus 74 [11] mm Hg postintervention), with this between-group difference being significant (P=0.04). Flow-mediated dilation improved in the IHT group (6.0% [5.7] preintervention versus 9.7% [5.5] postintervention), with no change in the control group (7.6% [5.5] preintervention versus 7.4% [5.1] postintervention), with this between-group difference being significant (P=0.04). There was no change in other measured variables over the intervention period. Conclusions IHT reduced brachial diastolic BP and improved local vascular function in patients with peripheral artery disease. Clinical Trial Registration URL: https://www.clinicaltrials.gov/. Unique identifier: NCT02742220.

Effects of isometric handgrip training on cardiac autonomic profile: A systematic review and meta-analysis study.

Meta-analyses have shown that isometric handgrip training reduces blood pressure in normotensive and hypertensive subjects. However, the effects on cardiac autonomic modulation are still controversial. Thus, the aim of this systematic review and meta-analysis was to analyse the effects of isometric handgrip training on cardiac autonomic modulation in normotensive and hypertensive subjects. For this, Medline, Cinhal, Embase, Spordiscus and PEdro were searched for relevant studies published until December 2018. Randomized controlled trials investigating the effect of isometric handgrip training on heart rate variability parameters were considered eligible. Parameters were obtained in time (standard deviation of all the RR intervals-SDNN, root mean square of successive differences between the normal adjacent RR intervals-RMSSD and the percentage of adjacent intervals with more than 50 ms-PNN50) and frequency domain (low frequency-LF, high frequency-HF and sympathovagal balance-LF/HF). Mean difference (MD) and 95% confidence interval (95% CI) were calculated using an inverse variance method with a random effects model. Seven trials were included in the systematic review and meta-analysis, totalling 86 participants. No significant effect was observed in heart rate variability parameters after isometric handgrip training (4 trials to SDNN: MD = -1.44 ms and 95% CI = -8.02, 5.14 ms; RMSSD: MD = -1.48 ms and 95% CI = -9.41, 6.45 ms; PNN50: MD = 0.85% and 95% CI = -1.10, 2.81%; 7 trials to LF: -0.17 n.u. and 95% CI = -6.32, 5.98 n.u.; HF: MD = 0.17 n.u. and 95% CI = -5.97, 6.30 n.u.; and LF/HF: MD = 0.13 and 95% CI = -0.34, 0.59). In conclusion, current literature indicates that isometric handgrip training does not improve heart rate variability.

Health self-perception and its association with physical activity and nutritional status in adolescents / Autopercepção de saúde e sua associação com atividade física e estado nutricional em adolescentes

Abstract Objective: To evaluate the association between total physical activities, physical activity in free time and nutritional status with self-perceived health in adolescents of both genders. Methods: This is a quantitative study that integrates the school-based, cross-sectional epidemiological survey with statewide coverage, whose sample consisted of 6261 adolescents (14 -19 years old) selected by random conglomerate sampling. Data were collected using the Global School-based Student Health Survey. The chi-squared test (χ 2) and the Poisson regression model with robust variance were used in the data analyses. Results: It was observed that 27.3% of the adolescents had a negative health self-perception, which was higher among girls (33.0% vs. 19.0%, p < 0.001). After adjusting for potential confounding factors, it was observed that boys who did not practice physical activity during free time (PR = 1.44, 95% CI: 1.15 -1.81) and were classified as insufficiently active (PR = 1.27, 95% CI: 1.04 -1.56), as well as girls who did not practice physical activity during free time (PR = 1.15, 95% CI: 1.02 -1.29) and were classified as overweight (PR = 1.27, 95% CI: 1.01 -1.29) had a greater chance of negative health self-perception. Conclusion: Behavioral issues may have different effects on health self-perception when comparing boys with girls. Negative health self-perception was associated with nutritional status in girls and a lower level of physical activity in boys, and the practice of physical activity in the free time was considered a protective factor against a negative health self-perception for adolescents of both genders.

Resumo Objetivo: Avaliar a associação entre atividade física total, atividade física no tempo livre e estado nutricional com a autopercepção de saúde em adolescentes de ambos os sexos. Métodos: Trata-se de um estudo com abordagem quantitativa, que integra o levantamento epidemiológico transversal de base escolar e abrangência estadual, cuja amostra foi constituída por 6.261 adolescentes (14 a 19 anos) selecionados por meio de uma estratégia de amostragem aleatória de conglomerados. Os dados foram coletados a partir do questionário Global School-based Student Health Survey. O teste de qui-quadrado (χ2) e o modelo de regressão de Poisson com variância robusta foram usados nas análises dos dados. Resultados: Observou-se que 27,3% dos adolescentes tinham uma autopercepção de saúde negativa, maior entre as meninas (33,0% vs. 19,0%; p < 0,001). Após o ajuste pelos potenciais fatores de confusão, constatou-se que tinham maior chance de ter uma autopercepção de saúde negativa os meninos que não praticavam atividade física no tempo livre (RP = 1,44; IC 95%: 1,15-1,81) e que eram classificados como insuficientemente ativos (RP = 1,27; IC 95%: 1,04-1,56) e as meninas que não praticavam atividade física no tempo livre (RP = 1,15; IC 95%: 1,02-1,29) e que eram classificadas como sobrepesadas (RP = 1,27; IC 95%: 1,01-1,29). Conclusão: Questões comportamentais podem ter diferentes repercussões na autopercepção de saúde quando comparados os meninos e meninas. A autopercepção de saúde negativa esteve associada ao estado nutricional entre as meninas e a um menor nível de atividade física entre os meninos e a prática de atividade física no tempo livre foi tida como fator de proteção para uma autopercepção de saúde negativa para os adolescentes de ambos os sexos.

Health self-perception and its association with physical activity and nutritional status in adolescents.

OBJECTIVE: To evaluate the association between total physical activities, physical activity in free time and nutritional status with self-perceived health in adolescents of both genders. METHODS: This is a quantitative study that integrates the school-based, cross-sectional epidemiological survey with statewide coverage, whose sample consisted of 6261 adolescents (14-19 years old) selected by random conglomerate sampling. Data were collected using the Global School-based Student Health Survey. The chi-squared test (χ2) and the Poisson regression model with robust variance were used in the data analyses. RESULTS: It was observed that 27.3% of the adolescents had a negative health self-perception, which was higher among girls (33.0% vs. 19.0%, p<0.001). After adjusting for potential confounding factors, it was observed that boys who did not practice physical activity during free time (PR=1.44, 95% CI: 1.15-1.81) and were classified as insufficiently active (PR=1.27, 95% CI: 1.04-1.56), as well as girls who did not practice physical activity during free time (PR=1.15, 95% CI: 1.02-1.29) and were classified as overweight (PR=1.27, 95% CI: 1.01-1.29) had a greater chance of negative health self-perception. CONCLUSION: Behavioral issues may have different effects on health self-perception when comparing boys with girls. Negative health self-perception was associated with nutritional status in girls and a lower level of physical activity in boys, and the practice of physical activity in the free time was considered a protective factor against a negative health self-perception for adolescents of both genders.

Acute blood pressure responses after different isometric handgrip protocols in hypertensive patients.

OBJECTIVE: The present study analyzed blood pressure responses after a single session of isometric handgrip exercise performed with different volumes and intensities by patients with hypertension. METHODS: This randomized crossover trial submitted 12 hypertensive patients (58±5 years old) to four isometric handgrip exercise sessions in a random order: 4 x 2 min at 30% of the maximal voluntary contraction (S30%); 4 x 2 min at 50% of the maximal voluntary contraction (S50%2min); 4 x 3 min at 30% of the maximal voluntary contraction (S30%3min); and a control session. The systolic and diastolic blood pressure, heart rate, and rate-pressure product were measured pre- and post-exercise (30th min). RESULTS: No significant changes were observed in cardiovascular variables after any session (p>0.05 for all comparisons). Similarly, individual analyses revealed heterogeneity in the responses, including increases in blood pressure observed in some sessions. Patients with reduced blood pressure after an isometric handgrip exercise session exhibited a higher body mass index, diastolic blood pressure and heart rate (p<0.05). They also tended to be younger (p=0.07). CONCLUSION: Isometric handgrip exercise performed with different intensities and volumes did not reduce the blood pressure of hypertensive patients.

Supervised, but Not Home-Based, Isometric Training Improves Brachial and Central Blood Pressure in Medicated Hypertensive Patients: A Randomized Controlled Trial.

Meta-analyses have shown that supervised isometric handgrip training reduces blood pressure in hypertensives. However, the mechanism(s) underlying these effects in medicated hypertensive patients, as well as the effects from home-based exercise training, is uncertain. The purpose of this study was to compare the effects of supervised and home-based isometric handgrip training on cardiovascular parameters in medicated hypertensives. In this randomized controlled trial, 72 hypertensive individuals (38-79 years old, 70% female) were randomly assigned to three groups: home-based, supervised isometric handgrip training or control groups. Home-based and supervised isometric handgrip training was completed thrice weekly (4 × 2 min at 30% of maximal voluntary contraction, with 1-min rest between bouts, alternating the hands). Before and after 12 weeks brachial, central and ambulatory blood pressures (BP), arterial stiffness, heart rate variability, vascular function, oxidative stress and inflammation markers were obtained. No significant (p > 0.05) effect was observed for ambulatory BP, arterial stiffness, heart rate variability, vascular function and oxidative stress and inflammatory markers in all three groups. Brachial BP decreased in the supervised group (Systolic: 132 ± 4 vs. 120 ± 3 mmHg; Diastolic: 71 ± 2 vs. 66 ± 2 mmHg, p < 0.05), whereas no significant differences were observed in the home-based (Systolic: 130 ± 4 vs. 126 ± 3 mmHg; diastolic: 73 ± 3 vs. 71 ± 3 mmHg) and control groups (p > 0.05). Supervised handgrip exercise also reduced central BP systolic (120 ± 5 vs. 109 ± 5 mmHg), diastolic (73 ± 2 vs. 67 ± 2 mmHg); and mean BP (93 ± 3 vs. 84 ± 3 mmHg), whereas no significant effects were found in the home-based (Systolic: 119 ± 4 vs. 115 ± 3 mmHg; Diastolic: 74 ± 3 vs. 71 ± 3 mmHg) and control groups (p > 0.05). In conclusion, supervised, but not home-based, isometric training lowered brachial and central BP in hypertensives.

Analysis of different anthropometric indicators in the detection of high blood pressure in school adolescents: a cross-sectional study with 8295 adolescents.

BACKGROUND: High blood pressure is strongly associated with obesity in different populations. However, it is unclear whether different anthropometric indicators of obesity can satisfactorily predict high blood pressure in the school setting. OBJECTIVES: This study evaluated the sensitivity and specificity of body mass index, waist circumference, and waist to height ratio in the detection of high blood pressure in adolescents. METHODS: The sample consisted of 8295 adolescents aged 10-17 years. Weight was measured using a digital scale, height with a stadiometer, and waist circumference using a tape measure. Blood pressure was measured by an automatic blood pressure measuring device. ROC curves were used for the analysis of sensitivity and specificity of the three anthropometric indices in identifying high blood pressure. Binary Logistic Regression was used to assess the association of body mass index, waist circumference, and waist to height ratio with high blood pressure. RESULTS: Low values of sensitivity were observed for body mass index (0.35), waist circumference (0.37), and waist to height ratio (0.31) and high values of specificity for body mass index (0.86), waist circumference (0.82), and waist to height ratio (0.83) in the detection of high blood pressure. An association was observed between adolescents classified with high body mass index (OR=3.57 [95% CI=3.10-4.10]), waist cirumference (OR=3.24 [95% CI=2.83-3.72]), and waist to height ratio (OR=2.94 [95% CI=2.54-3.40]) with high blood pressure. CONCLUSIONS: Body mass index, waist circumference, and waist to height ratio presented low sensitivity to identify adolescents with high blood pressure. However, adolescents classified with high body mass index, waist circumference, and waist to height ratio demonstrated a high association of presenting high blood pressure.

Acute effects of walking and combined exercise on oxidative stress and vascular function in peripheral artery disease.

The aim of this study was to compare the effects of a single session of walking and combined exercise on oxidative stress and vascular function in peripheral arterial disease patients. Thirteen patients with peripheral arterial disease underwent two experimental sessions in random order: walking (ten sets of 2-min walking at the speed corresponding to the onset of claudication pain with 2-min interval between sets) and combined exercise (1 × 10 reps in eight resistance exercises plus five-two-minute sets of walking). Before and after the exercise, vascular function (blood flow, leg vascular resistance and blood-flow postreactive hyperaemia) and oxidative stress (malondialdehyde and plasma nitrite levels) were obtained. Blood flow increased similarly after both sessions, whilst leg vascular resistance decreased similarly after both sessions. Plasma nitrite increased only after the combined exercise. Malondialdehyde decreased after both sessions, and the decrease was greater after combined exercise. As a conclusion, a single session of combined exercise improves blood flow and leg vascular resistance similarly to walking session; however, combined exercise promoted better effects on oxidative stress.

Acute blood pressure responses after different isometric handgrip protocols in hypertensive patients

OBJECTIVE: The present study analyzed blood pressure responses after a single session of isometric handgrip exercise performed with different volumes and intensities by patients with hypertension. METHODS: This randomized crossover trial submitted 12 hypertensive patients (58±5 years old) to four isometric handgrip exercise sessions in a random order: 4 x 2 min at 30% of the maximal voluntary contraction (S30%); 4 x 2 min at 50% of the maximal voluntary contraction (S50%2min); 4 x 3 min at 30% of the maximal voluntary contraction (S30%3min); and a control session. The systolic and diastolic blood pressure, heart rate, and rate-pressure product were measured pre- and post-exercise (30th min). RESULTS: No significant changes were observed in cardiovascular variables after any session (p>0.05 for all comparisons). Similarly, individual analyses revealed heterogeneity in the responses, including increases in blood pressure observed in some sessions. Patients with reduced blood pressure after an isometric handgrip exercise session exhibited a higher body mass index, diastolic blood pressure and heart rate (p<0.05). They also tended to be younger (p=0.07). CONCLUSION: Isometric handgrip exercise performed with different intensities and volumes did not reduce the blood pressure of hypertensive patients.