Epidemiological, mechanistic, and practical bases for assessment of cardiorespiratory fitness and muscle status in adults in healthcare settings.

Given their importance in predicting clinical outcomes, cardiorespiratory fitness (CRF) and muscle status can be considered new vital signs. However, they are not routinely evaluated in healthcare settings. Here, we present a comprehensive review of the epidemiological, mechanistic, and practical bases of the evaluation of CRF and muscle status in adults in primary healthcare settings. We highlight the importance of CRF and muscle status as predictors of morbidity and mortality, focusing on their association with cardiovascular and metabolic outcomes. Notably, adults in the best quartile of CRF and muscle status have as low as one-fourth the risk of developing some of the most common chronic metabolic and cardiovascular diseases than those in the poorest quartile. The physiological mechanisms that underlie these epidemiological associations are addressed. These mechanisms include the fact that both CRF and muscle status reflect an integrative response to the body function. Indeed, muscle plays an active role in the development of many diseases by regulating the body's metabolic rate and releasing myokines, which modulate metabolic and cardiovascular functions. We also go over the most relevant techniques for assessing peak oxygen uptake as a surrogate of CRF and muscle strength, mass, and quality as surrogates of muscle status in adults. Finally, a clinical case of a middle-aged adult is discussed to integrate and summarize the practical aspects of the information presented throughout. Their clinical importance, the ease with which we can assess CRF and muscle status using affordable techniques, and the availability of reference values, justify their routine evaluation in adults across primary healthcare settings.

In vivo absolute quantification of carnosine in the vastus lateralis muscle with 1H MRS using a surface coil and water as internal reference.

OBJECTIVE: To standardize a method for 1H MRS intramuscular absolute quantification of carnosine in the thigh, using a surface coil and water as internal reference. MATERIALS AND METHODS: Carnosine spectra were acquired in phantoms (5, 10, and 15 mM) as well as in the right gastrocnemius medialis (GM) and right vastus lateralis (VLM) muscles of young team sports athletes, using volume (VC) and surface (SC) coils on a 3 T scanner, with the same receiver gain. Water spectra were used as internal reference for the absolute quantification of carnosine. RESULTS: Phantom's experiments showed a maximum error of 7%, highlighting the validity of the measurements in the study setup. The carnosine concentrations (mmol/kg ww, mean ± SD) measured in the GM were 6.8 ± 2.2 with the VC (CcarVC) and 10.2 ± 3.0 with the SC (CcarSC) (P = 0.013; n = 9). Therefore, a correction was applied to these measurements (CcarVC = 0.6582*CcarSC), to make coils performance comparable (6.8 ± 2.2 for VC and 6.7 ± 2.0 for SC, P = 0.97). After that, only the SC was used to quantify carnosine in the VLM, where a concentration of 5.4 ± 1.5 (n = 30) was found, with significant differences between men (6.2 ± 1.3; n = 15) and women (4.6 ± 1.2; n = 15). The error in quantitation was 5.3-5.5% with both coils. CONCLUSION: The method using the SC and water as internal reference can be used to quantify carnosine in voluminous muscles and regions of the body in humans, where the VC is not suitable, such as the VLM.

Serum Levels of Myonectin Are Lower in Adults with Metabolic Syndrome and Are Negatively Correlated with Android Fat Mass.

Myonectin has shown beneficial effects on lipid regulation in murine models; therefore, it may have implications in the pathophysiology of metabolic syndrome (MS). We evaluated the relationship between serum myonectin and serum lipids, global and regional fat mass, intramuscular lipid content, and insulin resistance (IR) in adults with metabolic risk factors. This was a cross-sectional study in sedentary adults who were diagnosed with MS or without MS (NMS). Serum myonectin was quantified by enzyme-linked immunosorbent assay, lipid profile by conventional techniques, and free fatty acids (FFA) by gas chromatography. Body composition was assessed by dual-energy X-ray absorptiometry and intramuscular lipid content through proton nuclear magnetic resonance spectroscopy in the right vastus lateralis muscle. IR was estimated with the homeostatic model assessment (HOMA-IR). The MS (n = 61) and NMS (n = 29) groups were comparable in age (median (interquartile range): 51.0 (46.0-56.0) vs. 53.0 (45.5-57.5) years, p > 0.05) and sex (70.5% men vs. 72.4% women). MS subjects had lower serum levels of myonectin than NMS subjects (1.08 (0.87-1.35) vs. 1.09 (0.93-4.05) ng·mL-1, p < 0.05). Multiple linear regression models adjusted for age, sex, fat mass index and lean mass index showed that serum myonectin was negatively correlated with the android/gynoid fat mass ratio (R2 = 0.48, p < 0.01), but not with the lipid profile, FFA, intramuscular lipid content or HOMA-IR. In conclusion, serum myonectin is lower in subjects with MS. Myonectin negatively correlates with a component relevant to the pathophysiology of MS, such as the android/gynoid fat mass ratio, but not with other components such as FFA, intramuscular fat or IR.

Efficacy of high-intensity interval- or continuous aerobic-training on insulin resistance and muscle function in adults with metabolic syndrome: a clinical trial.

PURPOSE: We carried out a randomized, clinical trial in adults of both sexes with metabolic syndrome (MS) to assess the efficacy of high-intensity, low-volume interval training (HIIT) compared to moderate-intensity continuous training (MICT) on insulin resistance (IR), muscle mass, muscle activation, and serum musclin. METHODS: Fasting glycemia, insulinemia, and glycated haemoglobin were determined by conventional methods, IR by Homeostatic model assessment (HOMA), lean mass by Dual-Energy X-ray Absorptiometry, muscle activation through carnosine by Proton Magnetic Resonance Spectroscopy, and musclin by Enzyme-Linked ImmunoSorbent Assay before and after a supervised, three-times/week, 12-week treadmill programme. HIIT (n = 29) consisted of six intervals with one-minute, high-intensity phases at 90% of peak oxygen consumption (VO2peak). MICT (n = 31) trained at 60% of VO2peak for 30 min. RESULTS: Patients had a mean age of 50.8 ± 6.0 years, body mass index of 30.6 ± 4.0 kg/m2, and VO2peak of 29.0 ± 6.3 mL.kg-1.min-1. Compared to MICT, HIIT was not superior at reducing Ln HOMA-IR (adjusted mean difference: 0.083 [95%CI - 0.092 to 0.257]), carnosine or musclin or at increasing thigh lean mass. HIIT increased carnosine by 0.66 mmol/kg.ww (95% CI 0.08-1.24) after intervention. Both interventions reduced IR, body fat percentage and increased total lean mass/height2 and VO2peak. Musclin showed a non-significant reduction with a small effect size after both interventions. CONCLUSION: Compared to MICT, HIIT is not superior at reducing IR, carnosine or musclin or at increasing skeletal muscle mass in adults with MS. Both training types improved IR, muscle mass and body composition. NCT03087721, March 22nd, 2017. TRIAL REGISTRATION NUMBER: NCT03087721. Registered March 22nd, 2017.

Effects of Low-Volume, High-Intensity Interval Training Compared with Continuous Training on Regional and Global Body Composition in Adults with Metabolic Syndrome: A post hoc Analysis of a Randomized Clinical Trial.

OBJECTIVE: The aim of this study was to compare the effects of low-volume, high-intensity interval training (HIIT) or moderate-intensity continuous training (MICT) on body composition in adults with metabolic syndrome (MS). METHODS: This is a post hoc analysis of the randomized clinical trial Intraining-MET. Sixty adults (40-60 years old) were randomized to an MICT (n = 31) or HIIT (n = 29) supervised programme 3 days/week for 12 weeks. MICT sessions were conducted for 36 min at 60% of peak oxygen consumption (VO2peak). HIIT sessions included 6 intervals at 90% VO2peak for 1 min, followed by 2 min at 50% VO2peak. Body composition was assessed with dual energy X-ray absorptiometry. RESULTS: Body weight did not change from pre- to post-training in either MICT (78.9 ± 15.6 kg; 77.7 ± 16.5 kg, p = 0.280) or HIIT groups (76.3 ± 13.4 kg; 76.3 ± 13.7 kg, p = 0.964). Body fat percentage and fat mass (FM) decreased post-training in the MICT (-0.9%; 95% confidence interval [CI]: -0.27 to -1.47 and -0.7 kg; 95% CI: -0.12 to -1.30) and HIIT groups (-1.0%; 95% CI: -0.32 to -1.68 and -0.8 kg; 95% CI: -0.17 to -1.47). Compared to the HIIT programme, MICT significantly reduced android FM (-0.14 kg; 95% CI: -0.02 to -0.26). Lean mass (LM) increased post-training in MICT (+0.7 kg; 95% CI: 0.01-1.41) and HIIT groups (+0.9 kg; 95% CI: 0.12-1.64), but only HIIT increased the trunk LM (+0.6 kg; 95% CI: 0.06-1.20). CONCLUSIONS: Both MICT and HIIT reduced FM without changing body weight in adults with MS. MICT had additional benefits by reducing the android FM, whereas HIIT seemed to increase LM. Given the characteristics of the post hoc analysis, further research is required to confirm these results.

[Predictive validity of a functional classification method in older adultsValidação preditiva de método de classificação funcional em idosos]. / Validación predictiva de un método de clasificación funcional en adultos mayores.

OBJECTIVE: Evaluate the predictive validity of a functional classification (FC) method for the use of emergency services and hospitalization, mortality, and health care costs among older adults. METHODS: Retrospective cohort study that included 2 168 older adults in a chronic noncommunicable disease (CNCD) care program in Medellin, Colombia. Patients were stratified according to a FC method based on functional status, presence of risk factors, and control of comorbidity. During one year of follow-up, the predictive validity of the FC method was assessed for the studied outcomes. Discrimination and calibration were measured with the C-statistic and Hosmer-Lemeshow (HL) test, respectively. RESULTS: The average age was 74.6 ± 7.9 years; 40.8% (n = 884) were men and 7.7% (n = 168) died. The risk of death (odds ratio [OR]: 1.767; 3.411; 8.525), hospitalization (OR: 1.397; 2.172; 3.540) and high cost of health care (OR: 1.703; 2.369; 5.073) increased in proportion to a deterioration in functional classification (classes 2B, 3, and 4, respectively). The predictive model for the outcome of death showed good capacity for discrimination (C-statistic = 0.721) and calibration (HL statistic 10.200; P = 0.251). CONCLUSION: There is a dose-response relationship between deterioration in FC and a higher risk of death, hospitalization, and high cost. FC has predictive validity for the mortality rate and could be used to stratify older adults in CNCD care programs with a view to guiding interventions.

OBJETIVO: Avaliar a validade preditiva de um método de classificação funcional (CF) para a utilização de serviços de emergência e internação hospitalar, mortalidade e custos da atenção de saúde em idosos. MÉTODOS: Estudo de coorte retrospectivo com 2 168 idosos atendidos em um programa de atenção de doenças crônicas não transmissíveis (DCNT) em Medellín, Colômbia. Um método de CF foi usado para estratificar os participantes segundo o estado funcional, presença de fatores de risco e controle de comorbidades. No período de acompanhamento de um ano, a validade preditiva da CF foi avaliada para os desfechos de interesse. A capacidade discriminatória (estatística C) e a calibração (teste de Hosmer-Lemeshow [H-L]) do modelo foram avaliadas. RESULTADOS: A média de idade dos participantes do estudo foi 74,6 ± 7,9 anos, 40,8% (n = 884) eram do sexo masculino e 7,7% (n = 168) vieram a óbito. Houve aumento do risco de óbito (odds ratio [OR] 1,767; 3,411­8,525), internação hospitalar (OR 1,397; 2,172-3,540) e custo elevado da atenção de saúde (OR 1,703; 2,369­5,073) com o declínio funcional ­ classes funcionais 2B, 3 e 4, respectivamente. O modelo preditivo para o desfecho de óbito demonstrou boa capacidade discriminatória (estatística C = 0,721) e calibração (estatística H-L = 10,200; P = 0,251). CONCLUSÃO: Há uma relação de dose-resposta entre o declínio da CF e risco maior de óbito, internação hospitalar e custo elevado da atenção. A CF tem validade preditiva para a taxa de mortalidade e poderia ser utilizada na estratificação de idosos em programas de atenção de DCNT para ajudar a direcionar as medidas de intervenção.

Pulse wave velocity reference values in 3,160 adults referred to a hypertension clinic for 24-hour ambulatory blood pressure monitoring.

Background: Carotid-femoral pulse wave velocity (PWV) is a direct measure of aortic stiffness used in the stratification of cardiovascular risk. Its clinical application in Latin America has been limited by the absence of reference values. The objective of this study was to establish PWV reference values among adults referred to a specialized cardiology center for 24-hour ambulatory blood pressure monitoring (ABPM) in Medellín, Colombia.Methods: A descriptive study of 3,160 records of adult (older than 18 years) patients without pharmacological treatment assessed for PWV using a Mobil-O-Graph® 24-hour PWA device (IEM, Stolberg, Germany) and 24-hour ABPM with hemodynamic parameters based on suspected hypertension or hypotension was conducted. Patient records were categorized by decade of age and sub-divided based on the following 24-hour ABPM categories: normal (< 130/80 mmHg), grade I hypertension (between 130-150/80-90 mmHg), and grade II hypertension (> 150/90 mmHg).Results: PWV increased with age (r = 0,894; p < 0,001) and blood pressure category (ρ = 0,081; p < 0,001); the age-related increase was more pronounced among the patients in the higher blood pressure categories. Measures of central tendency and dispersion regarding PWV are presented, and reference values are proposed from the 90th percentile based on the age and 24-hour ABPM categories.Conclusions: PWV is directly related to age and blood pressure and can be predicted using a simple equation that includes these two variables. To stratify the cardiovascular risk of patients and make clinical decisions, the 90th percentile based on the age and 24-hour ABPM categories is recommended as a cut-off.

[Evaluation of the cost-effectiveness of an integral model of ambulatory treatment in patients with acute coronary syndrome: application of a probabilistic Markov modelAvaliação da relação custo-eficácia de um modelo integral de tratamento ambulatorial em pacientes com síndrome coronariana aguda: aplicação de um modelo probabilístico de Markov]. / Evaluación de la costo-efectividad de un modelo integral de tratamiento ambulatorio en pacientes con síndrome coronario agudo: aplicación de un modelo de Markov probabilístico.

OBJECTIVE: To evaluate the cost-effectiveness of an integral model of ambulatory treatment in patients who presented an acute coronary syndrome. METHODS: An economic evaluation was made from a quasi-experimental intervention study, which included 442 patients aged 30 to 70 years who presented an acute coronary syndrome. The intervention group (n = 165) received an integral model of ambulatory treatment based on managed care (disease management), while the control group (n = 277) received conventional cardiovascular rehabilitation. During one year of follow-up, the presentation of cardiovascular events and hospitalizations was evaluated. A probabilistic Markov model was developed. The study perspective was applied within the General System of Health Social Security in Colombia, including the direct health costs; the time horizon was 50 years with discounts of 3.42% for costs and effectiveness; and the measure of effectiveness was quality-adjusted life years (QALYs). A probabilistic and multivariate sensitivity analysis was performed using the Montecarlo simulation. RESULTS: During the year of follow-up, the direct costs related to the value paid were, on average, USD 2 577 for the control group and USD 2 245 for the intervention group. In the probabilistic sensitivity analysis, 91.3% of the simulations were located in the quadrant corresponding to incremental negative costs and positive incremental effectiveness (evaluated intervention at a lower cost, more effective). In the simulations, an average annual savings per patient of USD 1 215 per QALY was observed. CONCLUSIONS: The integral model of ambulatory treatment implemented in patients who suffered an acute coronary syndrome was found to be less expensive and more effective compared to conventional care. Considering it is a dominant alternative, it is recommended as a model of care in this population.

OBJETIVO: Avaliar a relação custo-eficácia de um modelo integral de tratamento ambulatorial em pacientes que apresentaram síndrome coronariana aguda. MÉTODOS: Uma avaliação econômica foi feita a partir de um estudo de intervenção quase experimental, que incluiu 442 pacientes com idade entre 30 a 70 anos que apresentaram síndrome coronariana aguda. O grupo de intervenção (n = 165) recebeu um modelo integral de tratamento ambulatorial com base em cuidados gerenciados (gerenciamento de doenças), enquanto o grupo controle (n = 277) recebeu reabilitação cardiovascular convencional. Durante um ano de acompanhamento, foi avaliada a apresentação de eventos cardiovasculares e hospitalizações. Um modelo probabilístico de Markov foi desenvolvido. A perspectiva do estudo foi aplicada no Sistema Geral de Segurança Social na Saúde da Colômbia, incluindo os custos diretos de saúde; o horizonte temporal foi de 50 anos com descontos de 3,42% em custos e efetividade; e a medida de eficácia foi os anos de vida ajustados pela qualidade (QALY). Uma análise de sensibilidade probabilística e multivariada foi realizada utilizando a simulação de Montecarlo. RESULTADOS: Durante o ano de acompanhamento, os custos diretos relacionados ao valor pago foram, em média, USD 2 577 para o grupo controle e USD 2 245 para o grupo de intervenção. Na análise de sensibilidade probabilística, foram localizadas 91,3% das simulações no quadrante correspondente a custos negativos incrementais e eficácia incremental positiva (intervenção avaliada a menor custo, mais efetiva). Nas simulações, observou-se uma economia anual média por paciente de US $ 1 215 por QALY. CONCLUSÕES: O modelo integral de tratamento ambulatorial implementado em pacientes que sofreram síndrome coronariana aguda foi considerado menos caro e mais eficaz em comparação com os cuidados convencionais. Por ser uma alternativa dominante, é recomendado como modelo de cuidados nesta população.

[Intervention with rumba and nutrition education to modify cardiovascular risk factors in adults with metabolic syndrome]. / Intervención con rumba y educación nutricional para modificar factores de riesgo cardiovascular en adultos con síndrome metabólico.

OBJECTIVE: Evaluate the effect of an intervention with rumba dance and nutrition education on the cardiovascular risk factors in a group of people with metabolic syndrome in a rural area of Colombia. METHODS: Controlled, randomized clinical trial that included 59 people between 30 and 60 years of age with metabolic syndrome. The intervention group (n = 30) participated in a 12-week exercise program of aerobic rumba (60 minutes, 3 days per week) and muscle-strengthening work (30 minutes, twice a week). Each week the group also received two hours of nutrition education. The control group (n = 29) continued with conventional care. An assessment was made of the effect on the cardiovascular risk factors (physiological, metabolic, anthropometric, and nutritional) in the intervention group. RESULTS: The intervention group showed a reduction in systolic blood pressure (-10.0 mmHg; CI95%: -14.3 to -5.6, P < 0.001), diastolic blood pressure (-4.8 mmHg; CI95%: -8.4 to -1.1, P < 0.05) and overall cardiovascular risk at 10 years (-1.5%; CI95%: -2.7 to -0.3, P < 0.05). Furthermore, there was an increase in peak oxygen con-sumption (1.7 ml O2∙kg-1∙min-1; CI95%: 0.1 to 3.3, P < 0.05) and muscular strength (P < 0.001). Positive changes were also observed in body composition, caloric intake, and consumption of macro and micronutrients (P < 0.05). No differences were detected between metabolic variables in the two groups or in inflammatory markers (P < 0.05). CONCLUSIONS: An exercise program with rumba and muscular strengthening, combined with nutrition education, favorably modifies cardiovascular risk factors in people with metabolic syndrome.

Sympathovagal quotient and resting-state functional connectivity of control networks are related to gut Ruminococcaceae abundance in healthy men.

INTRODUCTION: Heart rate variability (HRV), brain resting-state functional connectivity (rsFC), and gut microbiota (GM) are three recognized indicators of health status, whose relationship has not been characterized. We aimed to identify the GM genera and families related to HRV and rsFC, the interaction effect of HRV and rsFC on GM taxa abundance, and the mediation effect of diet on these relationships. METHODS: Eighty-eight healthy, young Colombian men were included in this cross-sectional study. HRV metrics were extracted from 24-hour Holter monitoring data and the resting functional connectivity strength (FCS) of 15 networks were derived from functional magnetic resonance imaging. Gut microbiota composition was assessed using the sequences of the V3-V4 regions of the 16 S rRNA gene, and diet was evaluated using a food frequency questionnaire. Multivariate linear regression analyses were performed to evaluate the correlations between the independent variables (HRV metrics and FCS) and the dependent variables (GM taxa abundance or alpha diversity indexes). Mediation analyses were used to test the role of diet in the relationship between HRV and GM. RESULTS: The sympathovagal quotient (SQ) and the FCS of control networks were positively correlated with the abundance of the gut Ruminococcaceae family and an unclassified Ruminococcaceae genus (Ruminococcaceae_unc). Additionally, the interaction between the FCS of the control network and SQ reduced the individual main effects on the Ruminococcaceae_unc abundance. Finally, reduced habitual fiber intake partially mediated the relationship between SQ and this genus. CONCLUSION: Two indicators of self-regulation, HRV and the rsFC of control networks, are related to the abundance of gut microbiota taxa in healthy men. However, only HRV is related to habitual dietary intake; thus, HRV could serve as a marker of food choice and GM composition in the future.

Regrowth of the psoas tendon after arthroscopic tenotomy: a magnetic resonance imaging study.

PURPOSE: The purpose of this study was to evaluate whether the psoas tendon regenerates after arthroscopic tenotomy through the central compartment of the hip in patients with internal snapping hip. METHODS: Twenty-seven patients with a snapping hip, aged 18 to 54 years (mean, 37.47 years), underwent arthroscopic tenotomy through the central compartment of the hip; all patients had symptomatic femoroacetabular impingement as well. The degree of regeneration was evaluated by preoperative and postoperative measurements of the tendon perimeter with a magnetic resonance imaging protocol in patients with more than 6 months' follow-up. In addition, function was assessed preoperatively and postoperatively with the Western Ontario and McMaster Universities Osteoarthritis Index score. Postoperative active flexion force was graded clinically between 1 and 5 with the Medical Research Council score. RESULTS: Eight patients had less than 6 months' follow-up, and they were excluded. The remaining 19 patients were evaluated after a mean follow-up period of 23.16 months (SD, 12.95 months). Tendon regeneration occurred in all patients. Compared with preoperative measurement, the psoas tendon circumference had recovered by 84.3% on average (55.44 ± 5.68 mm v 46.71 ± 6.05 mm, P < .001). Pain improved in all patients, and the mean Western Ontario and McMaster Universities Osteoarthritis Index score fell from 49 ± 15.9 points to 10.74 ± 11.35 points (P < .001). Muscle force recovered completely in all cases. CONCLUSIONS: There is a process of tissular repair after psoas tenotomy, and the findings on magnetic resonance imaging suggest that tendon tissue regrowth occurs. LEVEL OF EVIDENCE: Level IV, therapeutic case series.

Hemodynamic profiles of arterial hypertension with ambulatory blood pressure monitoring.

Blood pressure (BP) measurements obtained during a twenty-four-hour ambulatory blood pressure monitoring (24 h ABPM) have not been reliably applied to extract arterial hemodynamics. We aimed to describe the hemodynamic profiles of different hypertension (HT) subtypes derived from a new method for total arterial compliance (Ct) estimation in a large group of individuals undergoing 24 h ABPM. A cross-sectional study was conducted, which included patients with suspected HT. Cardiac output, Ct, and total peripheral resistance (TPR) were derived through a two-element Windkessel model without having a pressure waveform. Arterial hemodynamics were analyzed according to HT subtypes in 7434 individuals (5523 untreated HT and 1950 normotensive controls [N]). The individuals mean age was 46.2 ± 13.0 years; 54.8% were male, and 22.1% were obese. In isolated diastolic hypertension (IDH), the cardiac index (CI) was greater than that in normotensive (N) controls (CI: IDH vs. N mean difference 0.10 L/m/m2; CI 95% 0.08 to 0.12; p value <0.001), with no significant clinical difference in Ct. Isolated systolic hypertension (ISH) and divergent systolic-diastolic hypertension (D-SDH) had lower Ct values than nondivergent HT subtype (Ct: divergent vs. nondivergent mean difference -0.20 mL/mmHg; CI 95% -0.21 to -0.19 mL/mmHg; p value <0.001). Additionally, D-SDH displayed the highest TPR (TPR: D-SDH vs. N mean difference 169.8 dyn*s/cm-5; CI 95% 149.3 to 190.3 dyn*s/cm-5; p value <0.001). A new method is provided for the simultaneous assessment of arterial hemodynamics with 24 h ABPM as a single diagnostic tool, which allows a comprehensive assessment of arterial function for hypertension subtypes. Main hemodynamic findings in arterial HT subtypes with regard to Ct and TPR. The 24 h ABPM profile reflects the state of Ct and TPR. Younger individuals with IDH present with a normal Ct and frequently increased CO. Patients with ND-SDH maintain an adequate Ct with a higher TPR, while subjects with D-SDH present with a reduced Ct, high PP and high TPR. Finally, the ISH subtype occurs in older individuals with significantly reduced Ct, high PP and a variable TPR proportional to the degree of arterial stiffness and MAP values. There was an observed increase in PP with age in relation to the changes in Ct (see also text). SBP: systolic blood pressure; DBP: diastolic blood pressure; MAP: mean arterial pressure; PP: pulse pressure; N: normotension; HT: hypertension; IDH: isolated diastolic hypertension; ND-SDH: nondivergent systole-diastolic hypertension; D-SDH: divergent systolic-diastolic hypertension; ISH: isolated systolic hypertension; Ct: total arterial compliance; TPR: total peripheral resistance; CO: cardiac output; 24 h ABPM: 24 h ambulatory blood pressure monitoring.

Normative values for handgrip strength in Colombian children and adolescents from 6 to 17 years of age: estimation using quantile regression.

OBJECTIVE: The objective of this study is twofold: i) to estimate the normative values for handgrip strength and relative handgrip strength, specific to sex and age, for Colombian children and adolescents from 6 to 17 years of age using quantile regression models and ii) to compare the normative values for handgrip strength and relative handgrip strength in Colombian children and adolescents with those in children and adolescents in different countries. METHOD: This was a cross-sectional analysis of a sample of 2647 youngsters. Handgrip strength was evaluated with a TKK 5101 digital dynamometer (Takei Scientific Instruments Co., Ltd., Tokyo, Japan). The relative handgrip strength was estimated according to weight in kilograms. The normative values were estimated to handgrip strength and relative handgrip strength through quantile regression models for the percentiles P5, P10, P25, P50, P75, P90, and P95 developed independently for each sex. All analyses were adjusted for the expansion factor. RESULTS: The values for handgrip strength were considerably higher in males than in females in all age ranges. Additionally, as age increased for both sexes, the values for handgrip strength increased. The percentiles by sex and age for relative handgrip strength show for males a proportional increase according to age; for females, this did not occur. CONCLUSIONS: When making comparisons with international studies, variability is observed in the methodologies used to evaluate handgrip strength and estimation methods, which could influence the discrepancies between the different reports.

[Anthropometric and body composition characteristics associated with handgrip strength in children and adolescents. A scoping review]. / Características antropométricas y de composición corporal asociadas a la fuerza prensil manual en niños y adolescentes. Una Revisión Sistemática Exploratoria.

Handgrip strength is a robust indicator of the biological health of children and adolescents. Objecti ves: to identify the anthropometric characteristics and body composition related to handgrip stren gth, and to describe the main characteristics of the protocols used for its evaluation. METHODOLOGY: A scoping review was developed; the search was carried out in 1.) Medline; 2.) Web of Science; 3.) Science Direct; 4.) Scielo; and 5.) EBSCO's Sportdiscus. Original investigations were included if they have handgrip strength data, anthropometric characteristics, and body composition. RESULTS: 59 reports published between 2005 and 2020 were selected. Among them, nutritional classification was the most studied characteristic (n = 25; 42.3%), followed by body mass index (n = 23; 38.9%). In 47.5% (28 reports), the number of tests performed on each individual to estimate the handgrip strength value was not clear. The dynamometer brand Takei Scientific Instrument Co. Ltd. was the most used, with 49.2 %. The most widely used indicator was absolute handgrip (86.4%, 51 reports). CONCLUSIONS: There is a wide variety of protocols used for handgrip strength assessment with va riations in body position, arm and hand selection, number of repetitions, and intervals between measurements. A proportional pattern of values was found between absolute handgrip strength and body mass index, Σ skinfolds, however, when adjusted by mass (relative handgrip strength), the relationship is inverse.

Safety of High-Intensity, Low-Volume Interval Training or Continuous Aerobic Training in Adults With Metabolic Syndrome.

OBJECTIVE: The aim of the study was to evaluate the safety of high-intensity, low-volume interval training (HIIT-low volume) compared with moderate-intensity continuous aerobic training (MICT) in adults with metabolic syndrome. METHODS: This is a controlled, randomized, clinical trial in patients without history of ischemic heart disease or diabetes, who underwent a supervised, 3 sessions/week, 12-week treadmill exercise program. The HIIT-low volume (n = 29) sessions consisted of 6 intervals with 1-minute, high-intensity phases at 90% of peak oxygen consumption (VO2peak). The MICT (n = 31) trained at 60% of VO2peak for 30 minutes. A new approach to record and classify all clinical events according to possible causality based on Naranjo's algorithm was developed. RESULTS: Patients were 50.8 ± 6.0 years old, 70% women, with body mass index of 30.6 ± 4.0 kg/m2 and VO2peak of 29.0 ± 6.3 mL·kg-1·min-1. In total, 60 clinical events were recorded in the HIIT-low volume group and 48 in the MICT group, with 59.3% classified as general disease. Only 21 events were classified as adverse reactions possibly related to exercise, without any serious adverse reactions. Both interventions had a similar incidence of musculoskeletal events (incidence rate ratio, 1.1; 95% confidence interval, 0.6-1.8), but HIIT-low volume had a higher incidence of cardiovascular events (incidence rate ratio, 2.9; 95% CI, 0.4-22.8) after adjusting for age, sex, and body mass index (HIIT-low volume: chest pain [n = 1] and symptoms of venous insufficiency of lower limbs [n = 2]; MICT: chest pain [n = 1]). CONCLUSIONS: The HIIT-low volume and MICT are safe in patients with metabolic syndrome. We recommend a muscle-conditioning program prior to both and to avoid HIIT-low volume in treadmill in patients with venous insufficiency of the lower limbs.Trial registration number NCT03087721.

Validity and reproducibility of a method to estimate cardiorespiratory fitness in college adults / Validez y reproducibilidad de un método para estimar la capacidad cardiorrespiratoria en adultos universitarios

Introduction: Cardiorespiratory fitness is a predictor of cardiovascular and all-cause mortality. Its assessment in different groups has clinical and public health usefulness. Objective: To evaluate the validity and reproducibility of a no-exercise method [National Aeronautics and Space Administration (NASA) method] to estimate the maximum oxygen consumption (VO2máx) in college adults. Materials and methods: This study included 94 healthy individuals of both sexes (18-55 years). The gold standard was ergospirometry. The validity and reproducibility were evaluated with the intraclass correlation coefficient (ICC) and the Bland-Altman method. Results: Among the participants, we found a mean age of 30.54 ± 9.33 years and a VO2máx of 41.29 ± 9.54 ml O2.kg-1.min-1; 48.9 % were women. A mean difference of VO2máx between ergospirometry and that estimated by the NASA method of 3.41 ± 5.64 ml O2.kg-1.min-1 was found. The concordance between the two methods was good, with an ICC of 0.858 (CI95% 0.672-0.926). The percentage of error was 29.70 %. The reproducibility of the two estimates by the NASA method was excellent, with an ICC of 0.986 (CI95% 0.927-0.995). Conclusions: The NASA method is valid and reproducible to estimate VO2máx in college adults. In addition, it is safe and easy to apply. Estimating cardiorespiratory fitness is recommended to improve screening in cardiometabolic risk programs and to implement timely interventions.

Introducción. La capacidad física cardiorrespiratoria es un predictor de mortalidad por enfermedad cardiovascular y por todas las causas. Su diagnóstico en diferentes grupos tiene utilidad clínica y en salud pública. Objetivo. Evaluar la validez y reproducibilidad de un método sin ejercicio implementado por la NASA (National Aeronautics and Space Administration), para estimar el volumen máximo de oxígeno (VO2máx) consumido en adultos universitarios. Materiales y métodos. Estudio de validación de una prueba que incluyó 94 individuos sanos de ambos sexos (18 a 55 años). La prueba de referencia fue la ergoespirometría. La validez y la reproducibilidad se evaluaron mediante el coeficiente de correlación intraclase (Intraclass Correlation Coefficient, CCI) y el método de Bland-Altman. Resultados. Del total de los individuos incluidos en el estudio, 48,9 % fueron mujeres. La media de edad de los participantes fue de 30,54 ± 9,33 años y, la del VO2máx, fue de 41,29 ± 9,54 mlO2.kg-1.min-1. Se encontró una diferencia de medias de VO2máx entre la ergoespirometría y el estimado por el método implementado por la NASA de 3,41 ± 5,64 mlO2.kg-1.min-1. La concordancia entre los dos métodos fue buena, con un coeficiente de correlación intraclase de 0,858 (IC95% 0,672-0,926). El porcentaje de error fue del 29,70 %. La reproducibilidad de las dos estimaciones por el método implementado por la NASA fue excelente, con un coeficiente de correlación intraclase de 0,986 (IC95% 0,927-0,995). Conclusiones. El método NASA es válido y reproducible para estimar el VO2máx en adultos universitarios; además, es seguro y de fácil aplicación. Se recomienda la estimación de la capacidad física cardiorrespiratoria para mejorar la tamización en los programas de riesgo cardiometabólico e implementar intervenciones oportunas.

A novel method for the noninvasive estimation of cardiac output with brachial oscillometric blood pressure measurements through an assessment of arterial compliance.

OBJECTIVE: To propose and validate a new method for estimating cardiac output based on the total arterial compliance (Ct) formula that does not need an arterial waveform and to apply it to brachial oscillometric blood pressure measurements (OBPMs). METHODS: One hundred subjects with normal heart anatomy and function were included. Reference values for cardiac output were measured with echocardiography, and Ct was calculated with a two-element Windkessel model. Then, a statistical model of arterial compliance (Ce) was used to estimate cardiac output. Finally, the measured and estimated cardiac output values were compared for accuracy and reproducibility. RESULTS: The model was derived from the data of 70 subjects and prospectively tested with the data from the remaining 30 individuals. The mean age of the whole group was 43.4 ± 12.8 years, with 46% women. The average blood pressure (BP) was 107.1/65.0 ± 15.0/9.6 mmHg and the average heart rate was 67.7 ± 11.4 beats/min. The average Ct was 1.39 ± 0.27 mL/mmHg and the average cardiac output was 5.5 ± 1.0 L/min. The mean difference in the cardiac output estimated by the proposed methodology vs. that measured by Doppler echocardiography was 0.022 L/min with an SD of 0.626 L/min. The intraclass correlation coefficient was 0.93, and the percentage error was 19%. CONCLUSION: Cardiac output could be reliably and noninvasively obtained with brachial OBPMs through a novel method for estimating Ct without the need for an arterial waveform. The new method could identify hemodynamic factors that explain BP values in an ambulatory care setting.

Efficacy of high-intensity interval training compared with moderate-intensity continuous training on maximal aerobic potency in dogs: Trial protocol for a randomised controlled clinical study.

BACKGROUND: High-intensity interval training (HIIT) is a more efficient method to improve exercise capacity than moderate-intensity continuous training (MICT) because of its greater physiological stimulus. OBJECTIVE: The aim of this protocol is to evaluate the efficacy of HIIT on maximal aerobic potency in dogs as compared to MICT. METHODS: This protocol is for a randomised, blinded controlled clinical trial, with three parallel groups for the purpose of demonstrating superiority. Thirty dogs aged between 12 and 84 months of both sexes and different breeds will be included. Dogs, before initiating and after finalising the training will perform an incremental exercise test on a treadmill to obtain maximal speed and lactate threshold; resting parameters of heart and respiratory rate, left ventricle chamber and systolic function will be measured. Dogs assigned to each intervention will endure a 42-min session of HIIT or MICT during 12 weeks. HIIT comprises four intervals of 4 min each at a load of 85%, alternating with a 4-min resting period. MICT group will have a continuous load of 60%. The control group will remain in a cage. An intention-to-treat statistical analysis will be implemented. Analysis of covariance will be used to estimate the effect of HIIT compared with MICT training on maximal aerobic potency, aerobic resistance, systolic function at rest, left ventricle chamber measurements and indexes, respiratory rate and HR at rest. CONCLUSION: Significant time and effort are invested into training sports/working dogs, which could benefit from improving physical capacity by means of the HIIT methodology.

Musclin Is Related to Insulin Resistance and Body Composition, but Not to Body Mass Index or Cardiorespiratory Capacity in Adults.

BACKGROUND: We studied whether musclin function in humans is related to glycemic control, body composition, and cardiorespiratory capacity. METHODS: A cross-sectional study was performed in sedentary adults with or without metabolic syndrome (MS). Serum musclin was measured by enzyme-linked immunosorbent assay. Insulin resistance (IR) was evaluated by the homeostatic model assessment (HOMA-IR). Body composition was determined by dual-energy X-ray absorptiometry and muscle composition by measuring carnosine in the thigh, a surrogate of fiber types, through proton magnetic resonance spectroscopy. Cardiorespiratory capacity was assessed through direct ergospirometry. RESULTS: The control (n=29) and MS (n=61) groups were comparable in age (51.5±6.5 years old vs. 50.7±6.1 years old), sex (72.4% vs. 70.5% women), total lean mass (58.5%±7.4% vs. 57.3%±6.8%), and peak oxygen consumption (VO2peak) (31.0±5.8 mL O2./kg.min vs. 29.2±6.3 mL O2/kg.min). Individuals with MS had higher body mass index (BMI) (30.6±4.0 kg/m2 vs. 27.4± 3.6 kg/m2), HOMA-IR (3.5 [95% confidence interval, CI, 2.9 to 4.6] vs. 1.7 [95% CI, 1.1 to 2.0]), and musclin (206.7 pg/mL [95% CI, 122.7 to 387.8] vs. 111.1 pg/mL [95% CI, 63.2 to 218.5]) values than controls (P˂0.05). Musclin showed a significant relationship with HOMA-IR (ß=0.23; 95% CI, 0.12 to 0.33; P˂0.01), but not with VO2peak, in multiple linear regression models adjusted for age, sex, fat mass, lean mass, and physical activity. Musclin was significantly associated with insulin, glycemia, visceral fat, and regional muscle mass, but not with BMI, VCO2peak, maximum heart rate, maximum time of work, or carnosine. CONCLUSION: In humans, musclin positively correlates with insulinemia, IR, and a body composition profile with high visceral adiposity and lean mass, but low body fat percentage. Musclin is not related to BMI or cardiorespiratory capacity.

Hypertension and the roles of the 9p21.3 risk locus: Classic findings and new association data.

BACKGROUND: The band 9p21.3 contains an established genomic risk zone for cardiovascular disease (CVD). Since the initial 2007 Wellcome Trust Case Control Consortium study (WTCCC), the increased CVD risk associated with 9p21.3 has been confirmed by multiple studies in different continents. However, many years later there was still no confirmed report of a corresponding association of 9p21.3 with hypertension, a major CV risk factor, nor with blood pressure (BP). THEORY: In this contribution, we review the bipartite haplotype structure of the 9p21.3 risk locus: one block is devoid of protein-coding genes but contains the lead CVD risk SNPs, while the other block contains the first exon and regulatory DNA of the gene for the cell cycle inhibitor p15. We consider how findings from molecular biology offer possibilities of an involvement of p15 in hypertension etiology, with expression of the p15 gene modulated by genetic variation from within the 9p21.3 risk locus. RESULTS: We present original results from a Colombian study revealing moderate but persistent association signals for BP and hypertension within the classic 9p21.3 CVD risk locus. These SNPs are mostly confined to a 'hypertension island' that spans less than 60 kb and coincides with the p15 haplotype block. We find confirmation in data originating from much larger, recent European BP studies, albeit with opposite effect directions. CONCLUSION: Although more work will be needed to elucidate possible mechanisms, previous findings and new data prompt reconsidering the question of how variation in 9p21.3 might influence hypertension components of cardiovascular risk.