High-intensity interval training prevents muscle mass loss in overweight Chilean young adults during a hypocaloric-Mediterranean diet: a randomized trial.

The hypocaloric Mediterranean diet (MD) mainly reduces fat mass but inevitably causes a loss of skeletal muscle mass. High-intensity interval training (HIIT) seems to have advantages in preserving muscle mass during a hypocaloric regime. Our study compares body composition and metabolic changes in overweight and obese Chilean women and men after 3 months of weight loss treatment with a Mediterranean-type hypocaloric diet, HIIT, or a combination of both. The study included 83 overweight or obese women and men between the ages of 25 and 50. The subjects were randomly assigned to one of the three intervention groups: (1) MD, (2) EX, and (3) MD + EX. Baseline and post-intervention measurements included: (a) body composition by dual-beam densitometry, muscle, and fat measurements by thigh ultrasound and computed tomography; (b) handgrip and quadriceps muscle strength; (c) exercise performance by peak oxygen consumption, peak load, work efficiency, and exercise energy expenditure; and (d) metabolic parameters. Out of 83 participants, the retention rate was 49% due to low compliance with the interventions. As expected, the MD group resulted in significantly greater weight loss (MD -7%, EX -0.6% and MD + EX -5.3%) and appendicular fat mass loss (MD -11.1%, EX -2.9, MD + EX -10.2%) but was associated with significant lean tissue loss (2.8%), which was prevented by HIIT (EX -0.1 and MD + EX -0.6%). Metabolic and glycoxidative parameters remained unchanged, irrespective of changes in body composition. Hypocaloric diets remain the most effective means to lose weight and body fat. However, it induces a loss of lean body mass when not accompanied by exercise training. This study shows that HIIT prevents the loss of muscle mass caused by a hypocaloric Mediterranean diet.

Ultrasound assessment of rectus femoris pennation angle and echogenicity. Their association with muscle functional measures and fat infiltration measured by CT scan.

BACKGROUND & AIMS: Ultrasound can be used to measure the pennation angle between muscle fiver and the presumed axis of force generation and muscle echogenicity as an indicator of muscle fat infiltration. We aimed to assess the association of the rectus femoris pennation angle and echogenicity with muscle functional measures. Also, to assess the concordance of rectus femoris echogenicity with muscle fat infiltration as determined by CT scan. METHODS: Rectus femoris ultrasound pennation angle and thickness were measured in 78 participants aged 69 (65,73) years (37 women). Also hand grip strength, gait speed in 4 m, the 12 min' walk and body composition by DEXA were measured. In a different group of 114 participants aged 44 (31,52) years (80 females), non-dominant rectus femoris echogenicity and thickness were measured by ultrasound and muscle fat infiltration was assessed by CT scan. Handgrip strength and quadriceps torque were also measured. RESULTS: There was a weak correlation between the pennation angle and rectus femoris thickness in men (r = 0.31 p = 0.05) but not in women (r = 0.29 NS). Women, but not men with a low pennation angle covered a longer distance during the 12 min' walk. The concordance between the z scores of rectus femoris echogenicity and CT radiological density was 0.43 (p < 0.01) and 0.01 (NS) in men and women, respectively. Men and women with an echogenicity below the 25th percentile had a higher quadriceps torque. Men with an echogenicity 25th percentile below 25th percentile had also a higher handgrip strength. CONCLUSIONS: Rectus femoris pennation angle had a weak or absent association with muscle performance. Rectus femoris echogenicity had a moderate overall concordance with radiological density by CT scan and was inversely associated with quadriceps torque. Therefore, echogenicity was associated with muscle strength, but pennation angle measurement did not contribute to the assessment of muscle function.

Obesity and impairment of pancreatic ß-cell function in early adulthood, independent of obesity age of onset: The Santiago Longitudinal Study.

AIM: We investigated the relation of time of onset and length of obesity with biomarkers of ß-cell function in early adulthood in an infancy cohort. MATERIAL AND METHODS: In 1039 23-year-olds, body-mass index (BMI) was measured at multiple time-points from enrollment. BMI trajectories were interpolated with cubic polynomials. Fasting glucose, insulin and adiponectin were measured at 23 years. Homeostatic model assessment-insulin resistance (HOMA-IR), HOMA-S, HOMA-ß, HOMA-adiponectin (AD) and disposition index (DI) were estimated. IR and non-alcoholic fatty liver (NAFL) were diagnosed. According to the BMI trajectory, five groups were defined: participants who were never obese (NOB); participants with obesity starting in adolescence and remained obese into adulthood (recent-onset obesity, ROB); participants who were obese in early childhood but transitioned to non-obesity as preadolescents (former obesity, FOB); participants who were obese in early childhood and remained obese into adulthood (persistent obesity, POB); participants with obesity starting in preadolescence and transitioned to non-obesity as adolescents (transient obesity; TOB). RESULTS: Obesity was present in 47% of participants during at least one time-point. ROBs and POBs had higher insulin, HOMA-IR and HOMA-ß, lower HOMA-S and DI, and higher prevalence of IR and NAFL at 23 years than NOBs, TOBs and FOBs. No differences were found in the ß-cell functionality of NOBs, TOBs and FOBs. CONCLUSIONS: Persistent and recent obesity are both related to IR, NAFL and a decline of ß-cell function in emerging adulthood. Defeating obesity in childhood or adolescence allows reaching emerging adulthood with ß-cell functioning similar to that of subjects who were NOB.

A Randomized, Double-Blind, Placebo-Controlled Clinical Trial of an Omega-3 Fatty Acid Supplement in Patients With Predialysis Chronic Kidney Disease.

OBJECTIVE: Omega-3 fatty acids may reduce albuminuria and cardiovascular risk factors in patients with chronic kidney disease (CKD). We aimed to assess the effects of omega-3 fatty acid supplementation on albuminuria, blood pressure, pulse wave velocity, and inflammatory markers in patients with CKD. METHODS: Patients with CKD and a urine albumin excretion of at least 30 mg/g creatinine were supplemented for 3 months with 3,666 mg/day of docosahexaenoic and eicosapentaenoic acids or a corn oil supplement. The study was double blind. At baseline, 6 weeks, and 12 weeks, fasting blood and morning spot urine samples were obtained. Blood pressure, carotid intima media thickness, and pulse wave velocity were measured. The main outcome measure was a reduction of ≥20% in urine albumin. RESULTS: One hundred patients were randomized (50 received omega-3 fatty acids and 50 received corn oil). Four patients who received omega-3 fatty acids and 5 who received vegetable oil were lost to follow-up. In patients receiving omega-3 fatty acids, the omega-3 index increased from 3.08 (2.32-3.81) to 5.48 (3.045-7.04) percent. A 20% reduction in urine albumin excretion was observed in 13 participants of the control group and 19 participants of omega-3 group (Fisher's exact P = .274). However, the supplement had a significant and positive effect on pulse wave velocity and triglyceride level. CONCLUSION: An omega-3 fatty acid supplement of 3,666 mg/day did not modify urine albumin excretion in patients with CKD but did improve pulse wave velocity and serum triglyceride levels.

Accuracy of a Semi-Quantitative Ultrasound Method to Determine Liver Fat Infiltration in Early Adulthood.

An inexpensive and simple method to determine non-alcoholic fatty liver disease (NAFLD) is the abdominal ultrasound, but there are still doubts about its accuracy. We assessed the precision of a semi-quantitative ultrasound method to determine liver fat infiltration, using magnetic resonance spectroscopy (MRS) as the reference. The study was conducted in youths from an ongoing cohort study. Clinical validation was performed, using receiver operating characteristic analysis, in n = 60 participants (22.6y; 50% males). Abdominal ultrasound was carried out with liver brightness (score 0-3), diaphragm attenuation (0-2) and liver vessel blurring (0-1) scored by two observers. Liver fat was estimated using MRS. Then, analytical validation was conducted in the remaining participants (n = 555; 22.7y; 51% males) using effects size estimates. An ultrasound score ≥4.0 had the highest sensitivity (78%) and specificity (85%) for NAFLD diagnosis. An area under the curve of 86% denotes a good diagnostic performance of the test, whereas a Kappa of 0.63 suggests substantial agreement of ultrasound vs. MRS. The analytical validation showed that participants having NAFLD according to ultrasound had an unhealthier cardiometabolic profile than participants without the condition. Abdominal ultrasound, combined with a semi-quantitative score system, is a reliable method to determine liver fat infiltration in young adults and should be encouraged whenever MRS is unavailable.

Efficacy of urine urea nitrogen measurement to assess the compliance with protein restricted diets / Eficacia de la medición de nitrógeno ureico urinario para evaluar la adherencia a dietas restringidas en proteínas

Background: protein restriction is the mainstay of dietary management of chronic kidney disease. Aim: to assess the usefulness of urine urea nitrogen measurement as a marker of protein restriction. Methods: healthy young participants were randomly divided in two groups. During 14 days, one group received a diet containing 30 kcal/kg body weight and 1 g protein/kg body weight and the other group received a diet with the same amount of calories and 0.6 g/kg of proteins. At baseline, seven days and 14 days, 24 h dietary recalls were answered by the participants. They collected 24 hour urine and provided spot urine samples at baseline and at the end of the intervention, to measure creatinine and urea nitrogen. Results: forty-one participants aged 29 ± 5 years completed the follow-up. According to 24h dietary recalls, the group receiving 0.6 g/kg protein reduced significantly the protein intake during the intervention from 0.88 ± 0.06 to 0.59 ± 0.05 g/kg/day. A significant reduction in 24 h urea nitrogen excretion was also observed in this group. In the group receiving 1 g/kg of protein, no significant changes in 24 h urea nitrogen excretion were observed. Among all participants, the odds ratio of observing a reduction in protein intake in the dietary survey was 5.75 (95% confidence intervals 1.29-25.55, p = 0.02), when a reduction in 24 h urea nitrogen excretion corrected by creatinine was observed. No changes were observed in urea nitrogen excretion in spot urine samples. Conclusions: repeated urea nitrogen excretion measured in 24 h urine samples can be a reliable indicator of dietary protein restriction

Introducción: la restricción proteica es fundamental en el manejo de la enfermedad renal crónica. Objetivo: evaluamos la utilidad de la medición de nitrógeno ureico urinario como marcador de restricción proteica. Métodos: participantes jóvenes sanos fueron divididos aleatoriamente en dos grupos. Un grupo recibió una dieta con 30 kcal/día/kg peso corporal y 1 g/proteína/día/kg peso corporal y el otro recibió una dieta con la misma cantidad de calorías pero con 0,6 g/kg peso corporal de proteína. Al inicio, a los siete y a los 14 días, los participantes respondieron una encuesta dietaria de recordatorio de 24 horas. Además, recolectaron orina de 24 horas y se les tomó una muestra aislada de orina al comienzo y a los 14 días de la intervención para medir creatinina y nitrógeno ureico. Resultados: cuarenta y un participantes de 29 ± 5 años completaron el estudio. El grupo que consumió 0,6 g/kg de proteínas redujo su ingesta proteica de 0,88 ± 0,06 a 0,59 ± 0,05 g/kg/día durante la intervención. En este grupo se observó una reducción significativa en la excreción urinaria de nitrógeno ureico en 24 horas. No se observó tal reducción en el grupo que consumió 1 g/kg de proteínas. La tasa de probabilidad de detectar una reducción en la ingesta proteica en las encuestas dietarias, cuando se observaba una disminución en la excreción urinaria de nitrógeno ureico/mg creatinina de 24 horas, fue de 5,75 (intervalos de confianza de 95% = 1,29-25,55, p = 0,02). No hubo cambios significativos en la excreción de nitrógeno ureico en las muestras aisladas de orina. Conclusión: las mediciones repetidas de nitrógeno ureico urinario en 24 horas son un marcador de restricción dietaria de proteínas

Efficacy of urine urea nitrogen measurement to assess the compliance with protein restricted diets.

INTRODUCTION: Background: protein restriction is the mainstay of dietary management of chronic kidney disease. Aim: to assess the usefulness of urine urea nitrogen measurement as a marker of protein restriction. Methods: healthy young participants were randomly divided in two groups. During 14 days, one group received a diet containing 30 kcal/kg body weight and 1 g protein/kg body weight and the other group received a diet with the same amount of calories and 0.6 g/kg of proteins. At baseline, seven days and 14 days, 24 h dietary recalls were answered by the participants. They collected 24 hour urine and provided spot urine samples at baseline and at the end of the intervention, to measure creatinine and urea nitrogen. Results: forty-one participants aged 29 ± 5 years completed the follow-up. According to 24h dietary recalls, the group receiving 0.6 g/kg protein reduced significantly the protein intake during the intervention from 0.88 ± 0.06 to 0.59 ± 0.05 g/kg/day. A significant reduction in 24 h urea nitrogen excretion was also observed in this group. In the group receiving 1 g/kg of protein, no significant changes in 24 h urea nitrogen excretion were observed. Among all participants, the odds ratio of observing a reduction in protein intake in the dietary survey was 5.75 (95% confidence intervals 1.29-25.55, p = 0.02), when a reduction in 24 h urea nitrogen excretion corrected by creatinine was observed. No changes were observed in urea nitrogen excretion in spot urine samples. Conclusions: repeated urea nitrogen excretion measured in 24 h urine samples can be a reliable indicator of dietary protein restriction.

INTRODUCCIÓN: Introducción: la restricción proteica es fundamental en el manejo de la enfermedad renal crónica. Objetivo: evaluamos la utilidad de la medición de nitrógeno ureico urinario como marcador de restricción proteica. Métodos: participantes jóvenes sanos fueron divididos aleatoriamente en dos grupos. Un grupo recibió una dieta con 30 kcal/día/kg peso corporal y 1 g/proteína/día/kg peso corporal y el otro recibió una dieta con la misma cantidad de calorías pero con 0,6 g/kg peso corporal de proteína. Al inicio, a los siete y a los 14 días, los participantes respondieron una encuesta dietaria de recordatorio de 24 horas. Además, recolectaron orina de 24 horas y se les tomó una muestra aislada de orina al comienzo y a los 14 días de la intervención para medir creatinina y nitrógeno ureico. Resultados: cuarenta y un participantes de 29 ± 5 años completaron el estudio. El grupo que consumió 0,6 g/kg de proteínas redujo su ingesta proteica de 0,88 ± 0,06 a 0,59 ± 0,05 g/kg/día durante la intervención. En este grupo se observó una reducción significativa en la excreción urinaria de nitrógeno ureico en 24 horas. No se observó tal reducción en el grupo que consumió 1 g/kg de proteínas. La tasa de probabilidad de detectar una reducción en la ingesta proteica en las encuestas dietarias, cuando se observaba una disminución en la excreción urinaria de nitrógeno ureico/mg creatinina de 24 horas, fue de 5,75 (intervalos de confianza de 95% = 1,29-25,55, p = 0,02). No hubo cambios significativos en la excreción de nitrógeno ureico en las muestras aisladas de orina. Conclusión: las mediciones repetidas de nitrógeno ureico urinario en 24 horas son un marcador de restricción dietaria de proteínas.

Sarcopenia: The need to establish different cutoff points of fat-free mass for the Chilean population.

OBJECTIVES: International cutoff points for the diagnosis of sarcopenia are not applicable to the Chilean population due to previous evidence of a lower lean mass and strength in this population. Dual-energy x-ray absorptiometry is used to establish fat-free mass cutoff points to define sarcopenia in the Chilean population and analyze its association with handgrip strength in older adults. METHODS: Appendicular fat-free mass (AFFM) was calculated from 4062 dual-energy x-ray absorptiometries of healthy Chileans, ages 18 to 99 y. Possible cutoff points for sarcopenia were obtained using four methods: A) Normative, -2 standard deviation (SD) below mean AFFM/height2 (AFFMI) of adults age <40 y; B) normative -1 SD, -1 SD under the average AFFMI of adults age <40 y; C) stratification, 25th percentile of the residual distribution obtained with the regression equation to predict AFFM in the entire sample; and D) percentage, -2 SD under the average skeletal muscle mass/total body mass of individuals age <40 y. Additionally, in a subsample of elderly subjects, the correlation between handgrip strength and the four calculated cutoff points was analyzed. RESULTS: Using the normative method, sarcopenia was defined as an AFFMI <6.4 kg/m2 in men and <4.8 kg/m2 in women and at -1 SD, the cutoff points were <7.5 kg/m2 and <5.6 kg/m2, respectively. With the stratification method, sarcopenia was defined as -1.33 kg and -1.05 kg of AFFM with respect to the expected value according to the regression equation in men and women, respectively. According to the percentage method, the cutoff points for sarcopenia were <30% and <22.9% in men and women, respectively. The concordance of the four methods was slight to moderate. Only the percentage method showed a progressive increase in the proportion of subjects with sarcopenia as age increased. The latter and the normative -1 DS predicted lower handgrip strength in elderly women, unlike the other diagnostic methods. For elderly men, only the normative -1 DS method predicted weaker handgrip strength. CONCLUSIONS: The AFFM of young Chileans is lower than that reported in Western countries but similar to Latin American data; therefore, the use of the traditional normative method would not be appropriate with -2 SD to establish cutoff points, and using -1 DS resulted in values that are higher than Baumgartner's. Stratification is advantageous because this method throws expected values of AFFM for each population; however, overdiagnosis of sarcopenia is a possibility and thus the method requires a representative sample. The percentage method is simple and showed the expected decrease of muscle mass with age, and also correlated well with handgrip strength in elderly women. Thus, this method represented our method of choice to detect sarcopenia.

Association between activity energy expenditure and peak oxygen consumption with sarcopenia.

BACKGROUND: Sedentariness may be an important risk factor for sarcopenia. The aim of this work was to assess the association between muscle mass and strength and markers of usual physical activity such as activity energy expenditure and peak oxygen uptake. METHODS: Young and old participants were assessed measuring body composition by DEXA (double beam X ray absorptiometry), handgrip strength, peak oxygen consumption and workload during an exercise calorimetry in a braked cycle ergometer and a 72 h activity energy expenditure using Actiheart actigraphs. A heart rate/energy expenditure curve derived from the exercise calorimetry was used to calibrate each actigraph. Sarcopenia was defined as having an appendicular fat free mass index below 7.5 kg/m2 and 5.6 kg/m2 in men and women respectively, or a handgrip strength z score below 1, using local normal data or having both parameters below the cutoff points. RESULTS: We analyzed data from 192 assessments performed in participants aged 22 to 88 years (106 women). Sarcopenic participants (as determined by muscle mass, strength or both) had a significantly lower peak oxygen uptake and work load and a significantly lower activity energy expenditure. When analyzing lean mass and strength as continuous variables, peak oxygen consumption was a significant predictor of fat free mass in men. Among women, the association was observed only when percentage of muscle mass was expressed as a z score. CONCLUSIONS: Activity energy expenditure and peak oxygen consumption are associated with a lower muscle mass and the presence of sarcopenia and should be considered as risk factors for this condition.

Maximal expiratory pressure predicts mortality in patients hospitalized in medical and surgical wards.

BACKGROUND: the prognostic value of maximal inspiratory and expiratory pressures on functional capacity and mortality of hospitalized patients are not well established. AIM: to evaluate the prognostic value of respiratory pressures in hospitalized patients. METHODS: patients admitted to a general hospital in Santiago-Chile were prospectively studied. Within 48 hours of admission, handgrip strength and inspiratory and expiratory pressures were measured. Subjective global assessment of nutritional status (SGA) was determined and Apache II score was calculated. Functional status was assessed using the Karnofski index. Patients were followed for a period of 30 days. Mortality and decline in functional capacity, defined as a reduction in at least two stages of the Karnofski index were determined. Normal values for handgrip strength and respiratory pressures were obtained in 366 healthy subjects aged 20 to 89 years, thus the results obtained in patients were expressed as age and sex matched z-scores. RESULTS: one hundred and eight patients were recruited and 18 had to be excluded. Thus, 90 patients aged 58 ± 16 years (46 females) were studied. During the observation period, six patients died and nine experienced a decline in functional status. Patients who died had significantly lower maximal inspiratory and expiratory pressures, hand grip strength and worse SGA. Logistic regression analysis only accepted maximal expiratory pressure expressed as z-score as a predictor of mortality. In addition, it was the only significant predictor of death or functional decline. CONCLUSIONS: maximal expiratory pressure on admission was a predictor of death or functional decline at 30 days.

Maximal expiratory pressure predicts mortality in patients hospitalized in medical and surgical wards / La presión espiratoria máxima es un predictor de mortalidad en pacientes hospitalizados en servicios de medicina o cirugía

Background: the prognostic value of maximal inspiratory and expiratory pressures on functional capacity and mortality of hospitalized patients are not well established. Aim: to evaluate the prognostic value of respiratory pressures in hospitalized patients. Methods: patients admitted to a general hospital in Santiago-Chile were prospectively studied. Within 48 hours of admission, handgrip strength and inspiratory and expiratory pressures were measured. Subjective global assessment of nutritional status (SGA) was determined and Apache II score was calculated. Functional status was assessed using the Karnofski index. Patients were followed for a period of 30 days. Mortality and decline in functional capacity, defined as a reduction in at least two stages of the Karnofski index were determined. Normal values for handgrip strength and respiratory pressures were obtained in 366 healthy subjects aged 20 to 89 years, thus the results obtained in patients were expressed as age and sex matched z-scores. Results: one hundred and eight patients were recruited and 18 had to be excluded. Thus, 90 patients aged 58 ± 16 years (46 females) were studied. During the observation period, six patients died and nine experienced a decline in functional status. Patients who died had significantly lower maximal inspiratory and expiratory pressures, hand grip strength and worse SGA. Logistic regression analysis only accepted maximal expiratory pressure expressed as z-score as a predictor of mortality. In addition, it was the only significant predictor of death or functional decline. Conclusions: maximal expiratory pressure on admission was a predictor of death or functional decline at 30 days

Antecedentes: el valor pronóstico de las presiones inspiratoria y espiratoria máximas para determinar pérdida de capacidad funcional y mortalidad en pacientes hospitalizados, no está bien establecido. Objetivo: determinar el valor pronóstico de presiones respiratorias en pacientes hospitalizados. Métodos: se estudiaron pacientes ingresados a un hospital general en Santiago, Chile. Dentro de las primeras 48 horas de internación se midió fuerza de agarre de la mano, presión inspiratoria y espiratoria máximas. Se efectuó una evaluación global subjetiva del estado nutritivo (EGS) y se calculó el puntaje Apache II. El estado funcional se evaluó con el índice de Karnofski. Los pacientes fueron seguidos durante 30 días. Se determinó mortalidad y declinación de la capacidad funcional, definida como una pérdida de 2 o más etapas del índice de Karnofski. Se determinaron valores normales de presiones respiratorias y fuerza de agarre de la mano en 366 personas sanas con edades entre 20 y 89 años. Los resultados obtenidos en los pacientes se expresaron como puntaje z de estos valores, de acuerdo a sexo y edad. Resultados: se reclutaron 108 pacientes y 18 fueron excluidos. Por lo tanto se estudiaron 90 pacientes con una edad de 58 ± 16 años (46 mujeres). Durante el periodo de observación, seis pacientes murieron y nueve tuvieron un deterioro de y capacidad funcional. Los pacientes que murieron tuvieron presiones inspiratorias y espiratorias, y fuerza de agarre de la mano más baja y una EGS menor. La regresión logística solo aceptó a la presión espiratoria máxima expresada como puntaje z, como predictor de mortalidad. También fue el único predictor de mortalidad o declinación funcional. Conclusiones: la presión espiratoria máxima al ingreso, fue un predictor de mortalidad o declinación funcional a 30 días en pacientes hospitalizados

Effects of Two Training Modalities on Body Fat and Insulin Resistance in Postmenopausal Women.

Henríquez, S, Monsalves-Alvarez, M, Jimenez, T, Barrera, G, Hirsch, S, de la Maza, MP, Leiva, L, Rodriguez, JM, Silva, C, and Bunout, D. Effects of two training modalities on body fat and insulin resistance in postmenopausal women. J Strength Cond Res 31(11): 2955-2964, 2017-Our objective was to compare the effects of a low-load circuit resistance training protocol and usual aerobic training in postmenopausal women. Postmenopausal women with at least 1 feature of the metabolic syndrome were randomly allocated to a low-load circuit resistance training protocol or traditional aerobic training in a braked cycle ergometer. The intervention consisted in supervised sessions lasting 40 minutes, 3 times per week, during 6 months. At baseline and at the end of the intervention, fasting serum lipid levels, serum interleukin 6, C-reactive protein, 8 isoprostanes, and insulin resistance (assessed through QUICKI and HOMA-IR) were measured. Body fat was measured by double-beam X-ray absorptiometry and by computed tomography densitometric quantification at lumbar 3 vertebral level. Twenty-one women aged 58 (54-59) years were allocated to aerobic training and 21 women aged 55 (52-61) years were allocated to the low-load circuit resistance training protocol. Eighteen and 16 women in each group completed the 6 months training period. Women in both groups experienced significant reductions in blood pressure, total body, subcutaneous, and intraabdominal body fat. Reductions in total cholesterol and triacylglycerol levels were also observed. No changes in insulin resistance indexes, 8 isoprostanes, C-reactive protein, or interleukin 6 were observed in either group. No significant differences between treatment groups were observed in any of the measured parameters. We conclude that low-load circuit resistance training and aerobic training resulted in the same reductions in body fat and serum lipid levels.

Irisin is weakly associated with usual physical activity in young overweight women

PURPOSE: To determine if irisin plasma levels are associated with regular physical activity, body composition and metabolic parameters in women subjected to calorie restriction. SUBJECTS AND METHODS: We studied 42 women aged 34 ± 13 years with a body mass index of 27.7 ± 1.8 kg/m2, who were subjected to a calorie restriction for three months. At baseline and at the end of the study, weight, waist and hip circumference, laboratory parameters, body composition by DEXA, resting and activity energy expenditure by indirect calorimetry and 72 hours actigraphy were measured. Fasting serum irisin was quantified using an ELISA kit. RESULTS: After the intervention period, participants lost 1.5 (0.4-3.4) kg and irisin levels did not change. Irisin baseline levels were positively but weakly correlated with the level of physical activity. This association was lost at the end of the intervention. No association was found between irisin levels and body composition or insulin sensitivity or their changes after calorie restriction. No association between serum irisin levels and PGC-1αexpression in peripheral blood mononuclear cells and serum irisin was observed. CONCLUSIONS: Fasting serum irisin was weakly associated with usual physical activity and did not change after calorie restriction.

Irisin is weakly associated with usual physical activity in young overweight women / La irisina se asocia débilmente con la actividad física habitual en mujeres jóvenes con sobrepeso

Purpose: To determine if irisin plasma levels are associated with regular physical activity, body composition and metabolic parameters in women subjected to calorie restriction. Subjects and methods: We studied 42 women aged 34 ± 13 years with a body mass index of 27.7 ± 1.8 kg/m2, who were subjected to a calorie restriction for three months. At baseline and at the end of the study, weight, waist and hip circumference, laboratory parameters, body composition by DEXA, resting and activity energy expenditure by indirect calorimetry and 72 hours actigraphy were measured. Fasting serum irisin was quantified using an ELISA kit. Results: After the intervention period, participants lost 1.5 (0.4-3.4) kg and irisin levels did not change. Irisin baseline levels were positively but weakly correlated with the level of physical activity. This association was lost at the end of the intervention. No association was found between irisin levels and body composition or insulin sensitivity or their changes after calorie restriction. No association between serum irisin levels and PGC-1α expression in peripheral blood mononuclear cells and serum irisin was observed. Conclusions: Fasting serum irisin was weakly associated with usual physical activity and did not change after calorie restriction (AU)

Objetivo: determinar si los niveles plasmáticos de irisina se asocian con la actividad física regular, composición corporal y parámetros metabólicos en mujeres sometidas a restricción calórica. Material y métodos: estudiamos 42 mujeres de 34 ± 13 años con un índice de masa corporal de 27,7 ± 1,8 kg/m2, quienes fueron sometidas a una restricción calórica durante tres meses. Al comienzo y final del estudio, se midieron peso, circunferencias de cintura y cadera, parámetros de laboratorio, composición corporal usando DEXA y gasto energético en reposo y en actividad mediante calorimetría indirecta y actigrafía. La irisina en ayunas se midió utilizando un kit ELISA. Resultados: después del periodo de intervención, las participantes bajaron 1,5 (0,4-3,4) kg y los niveles de irisina no cambiaron. La irisina basal se relacionó de forma positiva pero débil con el nivel de actividad física de las participantes. Esta asociación se perdió al final de la intervención. No se encontró una asociación entre los niveles de irisina y la composición corporal o sensibilidad a insulina o el cambio de estos parámetros después del periodo de restricción calórica. No se observó asociación entre los niveles de irisina y la expresión de PGC-1α en monocitos periféricos. Conclusiones: La irisina en ayunas se asoció débilmente con la actividad física habitual y no cambió después de la restricción calórica (AU)

Admission handgrip strength predicts functional decline in hospitalized patients.

PROBLEM: Up to 35% of hospitalized patients may experience functional decline during or after hospitalization. Subjective Global Assessment (SGA) and handgrip strength at admission, have been proposed as simple and accessible tools to predict functional decline, but there are few studies in hospitalized patients to confirm these findings. OBJECTIVE: To assess the predictive value of handgrip strength at hospital admission, on functional decline after 30 days. METHODS: 125 non-critical patients hospitalized for medical and surgical conditions, were studied in El Pino hospital in Santiago, Chile. Upon admission, nutritional status was assessed by SGA, functional status through the Karnofsky index (KI), and handgrip strength by dynamometry. Change in functionality was assessed by the difference between KI at admission and 30 days later. Multivariate logistic regression models were used to establish associations between the variables at hospital admission, and subsequent functional decline. RESULTS: Thirty days post-hospital admission, 28.8% of the sample showed functional decline. In a multivariate analysis, only handgrip strength was associated with this decline (ß = -0.025, OR = 0.974 (CI 0.956-0.992), p = 0.007). CONCLUSIONS: Handgrip strength upon hospital admission can be a useful independent and early method to predict deterioration of functional status during hospitalization.

Associations between socioeconomic status, aging and functionality among older women.

To assess if there is an association between socioeconomic status and quality of life, functional status and markers of aging, we studied 86 women aged 73 ± 7 years, who answered the WHO Qol Bref quality of life survey. Mini mental state examination, timed up and go test, 12 minutes' walk, hand grip and quadriceps strength, dual X-ray absorptiometry (DEXA), carotid intima-media thickness and telomere length in peripheral leukocytes were measured. Successful aging was defined as a walking speed, handgrip strength, appendicular lean body mass, timed up and go and minimental values above cutoff points for disability. Participants with successful aging had a higher quality of life score and were more likely to live in rich municipalities. There was a positive correlation between telomere length, right handgrip strength and total fat free mass. Therefore, there is an association between socioeconomic status, successful aging and quality of life.

FACTORS RELATED TO TOTAL ENERGY EXPENDITURE IN OLDER ADULTS (CHILE).

AIM: to asses Total Energy Expenditure (TEE) in healthy Chilean institutionalized or independently older people Methods: twenty seven young (27-30 years), 27 institutionalized (> 65 years old) and 27 free-living older (> 65 years old) participants were studied. Body composition was estimated by dual energy X-ray absorptiometry. Physical activity energy expenditure (AEE) and TEE were assessed using Actiheart accelerometers. The Mini Nutritional Assessment (MNA) was applied and Timed Up and Go (TUG) was measured. RESULTS: AEE was 171, 320 and 497 kcal/day in institutionalized, free living older and young participants, respectively (p < 0.01 between young and older participants). Both absolute TEE and TEE/RMR was higher in young people. Multiple regression analysis accepted age, MNA and TUG as significant predictors of AEE (r2 = 0.24 p < 0.01). CONCLUSION: AEE and PAL were lower among older people, with no differences by institutionalization.

Objetivo: evaluar el Gasto Energético Total (GET) en ancianos sanos que viven institucionalizados o independientes en Chile. Método: se evaluaron veintisiete jovenes (27-30 años), 27 adultos mayores institucionalizados (> 65 años ) y 27 ancianos independientes (> 65 años). Se midió la composición corporal utilizando absorciometría bifotónica de rayos X. Se calculó el gasto energético por actividad física (GEAF) y el gasto energético total (GET) utilizando acelerómetros Actiheart; se aplicó Mini Nutritional Assessment (MNA) y se midió el Timed Up and Go (TUG). Resultados: el GEAF fue 171, 320 y 497 kcal/día en ancianos institucionalizados, independientes y jóvenes, respectivamente (p.

Factors related to total energy expenditure in older adults (Chile) / Factores relacionados con el gasto energético total en adultos mayores (Chile)

Aim: to asses Total Energy Expenditure (TEE) in healthy Chilean institutionalized or independently older people Methods: twenty seven young (27-30 years), 27 institutionalized (> 65 years old) and 27 free-living older (> 65 years old) participants were studied. Body composition was estimated by dual energy X-ray absorptiometry. Physical activity energy expenditure (AEE) and TEE were assessed using Actiheart accelerometers. The Mini Nutritional Assessment (MNA) was applied and Timed Up and Go (TUG) was measured. Results: AEE was 171, 320 and 497 kcal/day in institutionalized, free living older and young participants, respectively (p< 0.01 between young and older participants). Both absolute TEE and TEE/RMR was higher in young people. Multiple regression analysis accepted age, MNA and TUG as significant predictors of AEE (r2 = 0.24 p< 0.01). Conclusion: AEE and PAL were lower among older people, with no differences by institutionalization (AU)

Objetivo: evaluar el Gasto Energético Total (GET) en ancianos sanos que viven institucionalizados o independientes en Chile. Método: se evaluaron veintisiete jóvenes (27-30 años), 27 adultos mayores institucionalizados (> 65 años) y 27 ancianos independientes (> 65 años). Se midió la composición corporal utilizando absorciometría bifotónica de rayos X. Se calculó el gasto energético por actividad física (GEAF) y el gasto energético total (GET) utilizando acelerómetros Actiheart; se aplicó Mini Nutritional Assessment (MNA) y se midió el Timed Up and Go (TUG). Resultados: el GEAF fue 171, 320 y 497 kcal/día en ancianos institucionalizados, independientes y jóvenes, respectivamente (p <0,01 entre jóvenes y ancianos). Tanto el valor absoluto de GET como GET/GER fue más alto entre los jóvenes. El análisis de regresión múltiple aceptó la edad, el MNA y el TUG como predictores significativos de GEA (r2 = 0,24 p < 0,01). Conclusión: el GEAF y el nivel de actividad física (PAL) fueron más bajos en los adultos mayores, sin diferencias por institucionalización (AU)

Rectus femoris (RF) ultrasound for the assessment of muscle mass in older people.

BACKGROUND: Simple and reliable methods to evaluate muscle mass in older people are lacking. AIM: To evaluate ultrasound as a measure of RF muscle mass and quality in healthy subjects of different ages and gender, assessing its concordance with dual energy X-ray densitometry (DEXA) and association with muscle strength and walking capacity. METHODS: We selected 54 adults of both genders, aged 20-55 years and 51 adults older than 60 years. Ultrasound images of the RF were obtained at the mid-thigh to measure its thickness and ultrasonographic density using a GE Logiq e equipment. Body composition was assessed by DEXA. Quadriceps isometric strength and 12 minutes' walk were also measured and gender specific t scores for older adults were calculated using the values obtained in adults. RESULTS: RF ultrasound measurements correlated significantly with lean body mass assessed by DEXA (Double energy X-ray absorptiometry). The concordance between both measures was also adequate. Older people had lower muscle mass and worse ultrasound parameters than adults. Older males with a t score for quadriceps strength of -2 or less, had a significantly higher RF grayscale density. Older males with a 12 minutes' walk t score of -2 or less and old males and females with a walking speed of 1m/s or less had a lower RF thickness. DISCUSSION: There is a good concordance between RF ultrasound and DEXA. CONCLUSIONS: Assessment of RF using ultrasound appears to be a reliable and accurate method to evaluate muscle mass in older people.

Long-term fat redistribution in ARV-naïve HIV+ patients initiating a non-thymidine containing regimen in clinical practice.

INTRODUCTION: Lipodystrophy is still a matter of concern in HIV+ patients receiving ART. However, long-term fat change in patients taking non-thymidine regimens is not well known. MATERIALS AND METHODS: A prospective ongoing fat change assessment including clinical evaluation and dexa scans (Hologic QDR 4500) is being conducted in all consecutive patients initiating ART from January 2008. Arm, leg, trunk and total fat as well as fat mass ratio (FMR=% trunk fat/% leg fat) were determined. Patients with data at baseline (BL), 12 and 36 m are included in this analysis. ITT and OT were performed. Multivariate general linear models were used to assess changes in fat measures. RESULTS: One hundred patients were included. 81% men, 42.9 years, 18% AIDS, CD4 218.5 (6-756), viral load 5 log (2.9-6.8), leg fat 4644g, trunk fat 6693g, FMR 0.94. Around 40 patients (40%) initiated a PIr (17 LPVr, 11 ATVr, 9 DRVr, 3 FPVr), 34 (34%) NVP and 21 (21%) EFV. About 83% received TDF/FTC and 10% ABC/3TC. Groups were comparable at BL except for a lower viral load in NVP patients (p=0.047) and lower c-LDL in PI patients (p=0.043). After 36 m, no patient presented a clinically evident lipodystrophy. At 12 m, an overall significant increase was found from baseline in trunk, leg and FMR (median 759 g, 479.4 g and 0.03, respectively, p<0.05) and at 36 m in trunk and leg fat (median 989.9 g, 566 g, respectively, p<0.05). According to ART, at 12 m a significant increase in trunk and leg fat was observed in EFV and PIr. At 36 m, in NVP patients trunk and leg fat as well as FMR increased, whereas in PIr patients only leg fat increased (see figure). In ITT analysis, adjusted by age, sex, risk practice and BL CD4, EFV was associated with a greater increase in FMR (p=0.036) at 36 m vs PIr. In OT analysis, at 12 m, NVP was associated with a smaller percentage increase in trunk fat (vs PIr and EFV, p=0.006) and in leg fat (vs PIr, p=0.046). These differences did not persist at 36 m. CONCLUSIONS: In this cohort of patients taking non-thymidine-based regimens, after 36 m without a clinically evident lipodystrophy, no significant changes in FMR were observed. However, some differences in fat redistribution according to ART were present: PIr was associated with an initial and continuous increase in trunk and leg fat, NVP with a slower and progressive increase in both fat compartments, while in EFV patients, the initial fat increase was followed by a decrease in peripheral fat at 36 m. Longer follow up will help to confirm these trends.