Metabolic power and cardiovascular response of a low cadence-high height bench stepping exercise in healthy young people.

AIM: The aim of this paper was to study the feasibility of bench stepping at a low cadence as a safe exercise that can provide enough cardiovascular fitness that be performed by any person. METHODS: Thirty-three men and twenty-one young women (age =23±3 yrs; weight =70±13 kg; height 170±9 cm) participated in this study. Each one held a continuous 20 minute (4 stages /5 min each) bench stepping workout session with two different step heights (31 and 41 cm) and two different intensities (60 and 90 steps∙min-1). Body weight (bw), total & trochanteric height, heart rate (HR, beats∙min-1), rated perceived exertion (RPE) and O2 consumption (VO2) were recorded. RESULTS: From the 1st through the 4th stage, the vertical distance (VD, m), RPE, HR and VO2 values were 4.6-9.23 m, 2.5-6.7, 118-168 beats∙min-1 and 20.8-34.0 ml∙kg-1∙min-1, respectively. The best regression model to calculate the O2 consumption (VO2) was: VO2 (L∙min-1) =-1.264+0.026∙bw (kg)+0.195∙VD (m). VD, bw, and gender determined, independently, the changes of caloric expenditure (R2=0.92). CONCLUSION: The energy expenditure of a low cadence stepping exercise (15-22 cycles∙min-1) at 31-41 cm bench height, is enough to improve aerobic fitness which in turn may benefit cardiovascular health.

Effects of single sessions of low-intensity continuous and moderate-intensity intermittent exercise on blood lipids in the same endurance runners.

The factors responsible for the acute effects of exercise on blood lipids are not well known, and there have been few studies comparing different kinds of exercise in the same population. The concentration of blood lipids was evaluated in this study at the end and at post-24h of two 14km/90min single exercise sessions: continuous exercise (CE) at 44.5+/-5.6% VO(2max) and intermittent exercise (IE) at 39-72% VO(2max), in subjects with high levels of aerobic training. Fourteen male athletes (endurance runners) took part in this study and each completed a 24h dietary record. The O(2) uptake and CO(2) production were recorded, and blood lactate and blood lipids were measured. The results showed that triacylglycerols were not modified by any kind of exercise. Total cholesterol was increased at the end of both exercises: 7.04% for CE (p<0.001) and 4.23% for IE (p=0.001). High-density lipoprotein cholesterol was increased at the end of IE: 11.38% (p=0.03) and low-density lipoprotein cholesterol was increased only at the end of CE: 7.45% (p=0.006). The increase of lipids for CE was negatively correlated with aerobic fitness indicators (heart rate and %HRmax at lactate threshold), and was positively associated with energy expenditure. For IE, %HRmax and lactate were negatively correlated, and the respiratory exchange ratio was positively correlated, with the lipid increase. We conclude that in trained male athletes, a 14km run in 90min induced different changes of lipid profile if the exercise was done continuously or intermittently, and that in CE the extent of these increases was influenced by aerobic fitness.

Acute physiological response to indoor cycling with and without hydration; case and self-control study.

INTRODUCTION: Oral rehydration drinks help maintain physical capacity and hydration during exercise. OBJECTIVE: Evaluate, in a case and self-control study, the effectiveness of three hydration and exercise protocols on work capacity and physical and psychosomatic stress during indoor cycling (InC). METHODS: 14 middle-aged eutrophic men participated in three controlled randomly and not sequentially hydration (~278 mL 6/c 15 min) and exercise (InC/90 min) protocols: No liquids, plain water, or sports drinks (SD). The response variables were: Body temperature (BT), heart rate (HR), and mean blood pressure (MBP). The covariables: Distance traveled (DT), ergometer resistance (R), body fat (BF), difference in body weight between tests (rBW), and age of the participants. The differences between protocols were evaluated using GLM Repeated Measures, the independence of associations by multiple linear regression. RESULTS: In non-liquids, the subjects showed higher BT, HR, and MBP than when they drank plain water or SD (p < 0.01). Work capacity was the same in the three hydration protocols. BT was the most sensitive variable detected by the hydration status of the subjects. 34%, 99%, and 21% of the associated variance to HR, MBP, and BT was explained by DT + BT, BT + BF, and ΔBW + age + R + DT + BF, respectively. CONCLUSIONS: Liquid intake with or without electrolytes does not affect work capacity, and they are equally effective as hydration sources during =?90 min of InC at strong and very strong intensities. Body temperature is the most sensitive variable detected by the subject's hydration status during exercise.

Introducción: Las bebidas de re-hidratación oral ayudan a mantener la capacidad física y el nivel de hidratación durante el ejercicio. Objetivo: Evaluar en un estudio de casos y autocontroles la efectividad de tres protocolos de hidratación y ejercicio sobre la capacidad de trabajo, estrés físico y psicosomático durante el ciclismo de sala (CiS). Métodos: 14 varones eutróficos de mediana edad participaron de manera aleatoria y no consecutiva en tres protocolos de hidratación controlada (~278 mL 6/c 15 min) y ejercicio (CiS/90 min): No líquidos, agua corriente o bebida deportiva (BD). Las variables respuesta fueron: Temperatura corporal (TC), frecuencia cardiaca (FC) y presión sanguínea media (PSM). Las covariables: distancia recorrida (DR), resistencia del ergómetro (R) grasa corporal (GC), pérdida de peso al final del ejercicio ( PC) y edad de los participantes. Las diferencias entre los protocolos fueron evaluadas por GLM de Medidas Repetidas, la independencia de las asociaciones por regresión lineal múltiple. Resultados: En no líquidos, los sujetos presentaron mayor TC, FC y PSM que cuando ingirieron agua corriente o BD (p < 0,01). La capacidad de trabajo fue igual en los tres protocolos de hidratación. La TC fue la variable más sensible que detectó el estado de hidratación de los sujetos. El 34%, 99% y 21% de la varianza asociada a FC, PSM y TC lo explicaron DR + TC, TC + GC, y ?PC + edad + R + DR + GC respectivamente. Conclusiones: La ingesta de líquidos con o sin electrolitos no afecta la capacidad de trabajo y son igualmente efectivos como medios de hidratación durante =?90 min de Cis a intensidades pesadas y muy pesadas. La TC es la variable más sensible que detecta el estado de hidratación de los sujetos durante el ejercicio.

[Physiological and social factors associated with increments of body mass of Mexican young people with intellectual disabilities]. / Factores fisiológicos y sociales asociados a la masa corporal de jóvenes Mexicanos con discapacidad intelectual.

INTRODUCTION: Studies on the state of health and nutrition of Mexicans with intellectual disability (ID) including those with Down syndrome (DS), are scarce. OBJECTIVE: To analyze some physiological and social factors associated with the body mass of young people with ID from northern México. METHODS: Body weight, height and other anthropometric values were measured in fifty seven young (17 ± 5 years) participants with ID (DS,16%) and at least one guardian. BMI (kg/m²), somatotype and nutritional status were established by three international standards and total blood glucose, cholesterol & triacylglycerides, were also analyzed. Guardian's socio-economic, household food insecurity and nutrition literacy status were estimated with validated questionnaires by direct interview. RESULTS: Participants with SD were 12 cm smaller but subscapular skinfold (SECPS) was 6 mm thicker than that from other ID participants (p < 0.05). Prevalence of overweight/obesity was 70 and 44%, respectively. Blood biochemicals were similar between groups, but 25% had dyslipidemias. Participant's BMI correlated (p < 0,01) with several anthropometric & adiposity indicators (r = 0,40 a 0,88 ), blood triglycerides (r = 0,48 ) and cholesterol (r = 0,44) and guardians & participants' age (r = 0,35). The spending in food correlated (p < 0.05) with participant's SECPS (r = -0.33). The circumference of the waist, hip, calf and PSECP, 89% of the variance of the BMI explained. CONCLUSION: The body mass of young people with DI from northern Mexico, is strongly related to the degree of body adiposity, dyslipidemias, and some socio-economic factors of their family environment.