Overweight and Obese Adult Patients Show Larger Benefits from Concurrent Training Compared with Pharmacological Metformin Treatment on Insulin Resistance and Fat Oxidation.

Metformin, a drug widely used to treat insulin resistance, and training that combines aerobic and strength exercise modalities (i.e., concurrent training) may improve insulin sensitivity. However, there is a paucity of clinical trials investigating the effects of concurrent training, particularly on insulin resistance and fat oxidation in overweight and obese patients. Furthermore, only a few studies have compared the effects of concurrent training with metformin treatment. Therefore, the aim of this study was to examine the effects of a 12-week concurrent training program versus pharmaceutical treatment with metformin on maximum fat oxidation, glucose metabolism, and insulin resistance in overweight or obese adult patients. Male and female patients with insulin resistance were allocated by convenience to a concurrent training group (n = 7 (2 males); age = 32.9 ± 8.3 years; body mass index = 30 ± 4.0 kg·m-2) or a metformin group (n = 7 (2 males); age = 34.4 ± 14.0 years; body mass index = 34.4 ± 6.0 kg·m-2). Before and after the interventions, all participants were assessed for total body mass, body mass index, fat mass, fat-free mass, maximum oxygen consumption, maximal fat oxidization during exercise, fasting glucose, and insulin resistance through the homeostatic model assessment (HOMA-IR). Due to non-normal distribution of the variable maximal fat oxidation, the Mann-Whitney U test was applied and revealed better maximal fat oxidization (Δ = 308%) in the exercise compared with the metformin group (Δ = -30.3%; p = 0.035). All other outcome variables were normally distributed, and significant group-by-time interactions were found for HOMA-IR (p < 0.001, Δ = -84.5%), fasting insulin (p < 0.001, Δ = -84.6%), and increased maximum oxygen consumption (p = 0.046, Δ = 12.3%) in favor of the exercise group. Similar changes were found in both groups for the remaining dependent variables. Concurrent training seems to be more effective compared with pharmaceutical metformin treatment to improve insulin resistance and fat oxidation in overweight and obese adult patients with insulin resistance. The rather small sample size calls for more research in this area.

Recomendaciones de actividad física y ejercicio en el paciente adulto sometido a cirugía bariátrica. Documento de Consenso / Exercise and physical activity in adults who underwent bariatric surgery. Consensus document

Physical exercise is useful in people who underwent bariatric surgery. However, the right dosage is still a topic for discussion. The aim of this article is to consolidate the prescription criteria for physical activity and exercise in bariatric patients. A panel of experts to whom the topics were previously assigned for review, met to reach a consensus. Each topic was presented and subjected to discussion and voting by the participants and attendants who were exercise professionals from different obesity treatment centers. We report the conclusions reached for aerobic exercise, strength training, protein supplementation and physical activity for weight maintenance in bariatric patients.

[Exercise and physical activity in adults who underwent bariatric surgery. Consensus document]. / Recomendaciones de actividad física y ejercicio en el paciente adulto sometido a cirugía bariátrica. Documento de Consenso.

Physical exercise is useful in people who underwent bariatric surgery. However, the right dosage is still a topic for discussion. The aim of this article is to consolidate the prescription criteria for physical activity and exercise in bariatric patients. A panel of experts to whom the topics were previously assigned for review, met to reach a consensus. Each topic was presented and subjected to discussion and voting by the participants and attendants who were exercise professionals from different obesity treatment centers. We report the conclusions reached for aerobic exercise, strength training, protein supplementation and physical activity for weight maintenance in bariatric patients.

Oxygen pulse as a protective factor of insulin resistance in sedentary women with overweight or obesity.

BACKGROUND: obesity is associated with insulin resistance (IR). Through exercise, insulin resistant obese patients can effectively improve theircardiorespiratory fitness (CRF). The effect of exercise on patients CRF can be determined by oxygen pulse (PO2) analysis. Despite its usefulness, there is limited literature on PO2 analysis in patients with obesity and insulin resistance. OBJECTIVE: the goal of the present study is to evaluate the relation between PO2 and IR in sedentary obese women. METHODS: fifty-five women were submitted to a maximal exercise test for evaluation of maximal oxygen consumption and PO2. The subjects with a homeostatic model assessment of IR index greater or equal to 2.5 were considered as insulin-resistant (IR). Participants were divided into two groups, IR group (n = 35) and non-IR group (n = 20). RESULTS: the IR group had lower values of PO2 relative to body weight (11.0 ± 1.7 versus 12.6 ± 1.4 ml∙kg∙beats-1, p = 0.001) and relative to lean mass (21.7 ± 2.9 versus 23.2 ± 2.8 ml∙kg∙beats-1, p = 0.038) than non-IR group. No statistical differences were found in maximal oxygen consumption between the groups (non-IR = 1.53 ± 0.27 l∙min-1, IR = 1.51 ± 0.28 l∙min-1; p = 0.386). PO2 relative to body weight and HOMA-IR was inversely correlated (p < 0.001; r = -0.465). Logistic regression analysis showed an association between PO2 relative to weight (p = 0.001, OR = 0.47) and fat free mass (p = 0.01, OR = 0.73), both models adjusted by age. CONCLUSIONS: this study demonstrates a relation between HOMA-IR and PO2. Our results suggest that PO2 could be a protective factor against insulin resistance.

Oxygen pulse as a protective factor of insulin resistance in sedentary women with overweight or obesity / Pulso de oxígeno como factor protector de resistencia a la insulina en mujeres sedentarias con sobrepeso u obesidad

Background: obesity is associated with insulin resistance (IR). Through exercise, insulin resistant obese patients can effectively improve their cardiorespiratory fitness (CRF). The effect of exercise on patients CRF can be determined by oxygen pulse (PO2) analysis. Despite its usefulness, there is limited literature on PO2 analysis in patients with obesity and insulin resistance. Objective: the goal of the present study is to evaluate the relation between PO2 and IR in sedentary obese women. Methods: fifty-five women were submitted to a maximal exercise test for evaluation of maximal oxygen consumption and PO2. The subjects with a homeostatic model assessment of IR index greater or equal to 2.5 were considered as insulin-resistant (IR). Participants were divided into two groups, IR group (n = 35) and non-IR group (n = 20). Results: the IR group had lower values of PO2 relative to body weight (11.0 ± 1.7 versus 12.6 ± 1.4 ml∙kg∙beats-1, p = 0.001) and relative to lean mass (21.7 ± 2.9 versus 23.2 ± 2.8 ml∙kg∙beats-1, p = 0.038) than non-IR group. No statistical differences were found in maximal oxygen consumption between the groups (non-IR = 1.53 ± 0.27 l∙min-1, IR = 1.51 ± 0.28 l∙min-1; p = 0.386). PO2 relative to body weight and HOMA-IR was inversely correlated (p < 0.001; r = -0.465). Logistic regression analysis showed an association between PO2 relative to weight (p = 0.001, OR = 0.47) and fat free mass (p = 0.01, OR = 0.73), both models adjusted by age. Conclusions: this study demonstrates a relation between HOMA-IR and PO2. Our results suggest that PO2 could be a protective factor against insulin resistance

Introducción: la sensibilidad a la insulina ha sido ampliamente relacionada con el fitness cardiorrespiratorio (FCR), el cual puede ser evaluado a través del pulso de oxígeno (PO2). Este corresponde al producto entre el volumen sistólico y la diferencia arteriovenosa de oxígeno y en sujetos sin alteraciones cardiovasculares podría ser un indicador de alteraciones del metabolismo a nivel periférico como la resistencia a la insulina (RI). Objetivo: el objetivo del presente estudio es evaluar la relación entre el PO2 y la RI en mujeres sedentarias con obesidad. Métodos: cincuenta y cinco mujeres fueron sometidas a una prueba de ejercicio maximal para la evaluación del consumo máximo de oxígeno (VO2max) y del PO2. Los sujetos con un índice HOMA-IR mayor o igual a 2,5 fueron considerados con resistencia a la insulina. Los participantes fueron divididos en dos grupos, RI (n = 35) y no-RI (n = 20). Resultados: el grupo RI presentó valores menores de PO2 relativo al peso corporal (11,0 ± 1,7 versus 12,6 ± 1,4 ml∙kg∙latidos-1, p = 0,001) y relativo a la masa libre de grasa (21,7 ± 2,9 versus 23,2 ± 2,8 ml∙kg∙latidos-1, p = 0,038) respecto al grupo no-RI. No se encontraron diferencias estadísticamente significativas en el VO2max entre ambos grupos (no-RI = 1.53 ± 0.27 l∙min-1, RI = 1,51 ± 0,28 l∙min-1; p = 0,386). Se encontró una correlación inversa entre el PO2 relativo al peso y el índice HOMA-IR (p < 0,001; r = -0,465). El análisis de regresión logística mostró una asociación entre el PO2 relativo al peso (p = 0,001, OR = 0,47) y la masa libre de grasa (p = 0,01, OR = 0,73), ambos modelos ajustados por edad. Conclusiones: este estudio demuestra que existe una relación entre el índice HOMA-IR y el PO2. Estos resultados sugieren que el PO2 podría ser un factor protector de RI

Cardiorespiratory fitness and fat oxidation during exercise as protective factors for insulin resistance in sedentary women with overweight or obesity.

INTRODUCTION: obesity is a global pandemic and it is the biggest risk factor for death worldwide nowadays. Studies suggest that both cardiorespiratory fitness and fat oxidation in exercise are related to insulin resistance and type 2 diabetes mellitus, and they could be used as metabolic fitness markers. OBJECTIVES: the aim of this study is to determine if cardiorespiratory fitness (VO2) and fat oxidation during exercise are protective factors of insulin resistance (IR) in sedentary women with obesity or overweight. METHODS: sixty women were selected for fat oxidation analysis and 55 for cardiorespiratory fitness analysis that fitted the inclusion and exclusion criteria. VO2, maximal fat oxidation (MFO) and the intensity where MFO is reached (FATmax) were determined through an incremental test on a cycle ergometer with gas analysis. The subjects with a Homeostatic model assessment of IR index greater or equal to 2.5 were considered as insulin-resistant. Participants were divided into 2 groups, IR group (n = 38) and Non-IR group (n = 22). RESULTS: VO2(%) and MFO were lower in the IR group (76.1% vs.83.2%; p = 0.015 and 1.08 mg × kg-1 × min-1 vs. 1.62 mg × kg-1 × min-1; p= 0.044, respectively) compared to the Non-IR group. There was an association between VO2(%) and IR (OR = 0.92, p = 0.017) and between MFO and IR (OR = 0.52, p = 0.035), both models adjusted for age and body mass index. CONCLUSIONS: VO2(%) and MFO are independent protective factors for IR. No association was found between FATmax and IR.

Cardiorespiratory fitness and fat oxidation during exercise as protective factors for insulin resistance in sedentary women with overweight or obesity / Fitness cardiorrespiratorio y oxidación de grasas durante el ejercicio como factores protectores de resistencia a la insulina en mujeres sedentarias con sobrepeso u obesidad

Introduction: obesity is a global pandemic and it is the biggest risk factor for death worldwide nowadays. Studies suggest that both cardiorespiratory fitness and fat oxidation in exercise are related to insulin resistance and type 2 diabetes mellitus, and they could be used as metabolic fitness markers. Objectives: the aim of this study is to determine if cardiorespiratory fitness (VO2) and fat oxidation during exercise are protective factors of insulin resistance (IR) in sedentary women with obesity or overweight. Methods: sixty women were selected for fat oxidation analysis and 55 for cardiorespiratory fitness analysis that fitted the inclusion and exclusion criteria. VO2, maximal fat oxidation (MFO) and the intensity where MFO is reached (FATmax) were determined through an incremental test on a cycle ergometer with gas analysis. The subjects with a Homeostatic model assessment of IR index greater or equal to 2.5 were considered as insulin-resistant. Participants were divided into 2 groups, IR group (n = 38) and Non-IR group (n = 22). Results: VO2(%) and MFO were lower in the IR group (76.1% vs. 83.2%; p = 0.015 and 1.08 mg × kg-1 × min-1 vs. 1.62 mg × kg-1 × min-1; p = 0.044, respectively) compared to the Non-IR group. There was an association between VO2(%) and IR (OR = 0.92, p = 0.017) and between MFO and IR (OR = 0.52, p = 0.035), both models adjusted for age and body mass index. Conclusions: VO2(%) and MFO are independent protective factors for IR. No association was found between FATmax and IR

Introducción: la obesidad es una pandemia global y actualmente es el mayor factor de riesgo de muerte a nivel mundial. Estudios sugieren que tanto el fitness cardiorrespiratorio (VO2) como la oxidación de grasas durante el ejercicio podrían ser utilizados como marcadores del fitness metabólico. Objetivos: el objetivo de este estudio es determinar si el VO2 y la oxidación de grasas durante el ejercicio son factores protectores de resistencia a la insulina en mujeres sedentarias con obesidad o sobrepeso. Métodos: fueron seleccionadas 60 mujeres para análisis de oxidación de grasas y 55 para análisis de VO2 que cumplieran con los criterios de inclusión y exclusión. El VO2, la máxima oxidación de grasas (MFO) y la intensidad donde se alcanza el MFO (FATmax) fueron determinados mediante un test incremental en cicloergómetro con análisis de gases. Los sujetos con un índice HOMA-IR mayor o igual a 2,5 fueron considerados con resistencia a la insulina. Los participantes fueron divididos en dos grupos, IR (n = 38) y No-IR (n = 22). Resultados: el VO2(%) y la MFO fueron menores en el grupo IR en comparación al grupo No-IR (76,1% versus 83,2%; p = 0,015 y 1,08 mg × kg-1 × min-1 versus 1,62 mg × kg-1 × min-1; p = 0,044, respectivamente). Mediante el análisis de regresión logística se encontró una asociación entre VO2(%) e IR (OR = 0,92; p = 0,017) y entre MFO e IR (OR = 0,52; p = 0,035), ambos modelos ajustados por edad e índice de masa corporal. Conclusión: el VO2(%) y la MFO son factores protectores independientes de IR. No se encontró asociación entre el FATmax y la IR