Metabolic Effects of Aerobic Training and Resistance Training in Type 2 Diabetic Subjects

Abstract

OBJECTIVETo assess differences between the effects of aerobic and resistance training on HbA1c (primary outcome) and several metabolic risk factors in subjects with type 2 diabetes, and to identify predictors of exercise-induced metabolic improvement.RESEARCH DESIGN AND METHODSType 2 diabetic patients (n = 40) were randomly assigned to aerobic training or resistance training. Before and after 4 months of intervention, metabolic phenotypes (including HbA1c, glucose clamp–measured insulin sensitivity, and oral glucose tolerance test–assessed β-cell function), body composition by dual-energy X-ray absorptiometry, visceral (VAT) and subcutaneous (SAT) adipose tissue by magnetic resonance imaging, cardiorespiratory fitness, and muscular strength were measured.RESULTSAfter training, increase in peak oxygen consumption (VO2peak) was greater in the aerobic group (time-by-group interaction P = 0.045), whereas increase in strength was greater in the resistance group (time-by-group interaction P < 0.0001). HbA1c was similarly reduced in both groups (−0.40% [95% CI −0.61 to −0.18] vs. −0.35% [−0.59 to −0.10], respectively). Total and truncal fat, VAT, and SAT were also similarly reduced in both groups, whereas insulin sensitivity and lean limb mass were similarly increased. β-Cell function showed no significant changes. In multivariate analyses, improvement in HbA1c after training was independently predicted by baseline HbA1c and by changes in VO2peak and truncal fat.CONCLUSIONSResistance training, similarly to aerobic training, improves metabolic features and insulin sensitivity and reduces abdominal fat in type 2 diabetic patients. Changes after training in VO2peak and truncal fat may be primary determinants of exercise-induced metabolic improvement.

Efectos del entrenamiento contra resistencias o resistance training en diversas patologías

“…En relación con la composición corporal, algunas investigaciones han comprobado un efecto positivo del RT a la hora de disminuir el índice cintura/cadera (81) y los niveles de masa corporal y masa grasa (78,82,83), mientras que muchos otros han observado efectos importantes en el incremento de la masa magra (77)(78)(79)(80). Este efecto, a priori efectivo en relación con la composición corporal, se ve reforzado por el hecho de que las ganancias de la masa magra se acompañan de mejoras en la capacidad de producción de fuerza por unidad de masa magra (77).…”

Reply

“…1 This study was a subproject of the RAED2 Study, a randomized, controlled trial aimed at comparing the metabolic effects of RES and AER training in diabetic patients. 2 Pesta and Burtscher hypothesized that in untrained overweight/ obese subjects with little experience in exercise, RES training would be unable to induce the specific adaptations characteristic of this exercise modality, and that this, in turn, might explain why the results of AER and RES training were similar.…”

“…2,3 A functional microsatellite (GT) n repeat variant in the HO-1 promoter region is tightly correlated with inducibility of HO-1 protein expression, i.e., short (<26) (GT) n repeat carriers present increased HO-1-expression-derived antiinflammatory and cytoprotective effects. 4 As opposed to cardiac or pulmonary disease, HO-1 gene polymorphisms in human liver disease have been largely unexplored.…”

“…1 This study was a subproject of the RAED2 Study, a randomized, controlled trial aimed at comparing the metabolic effects of RES and AER training in diabetic patients. 2 Pesta and Burtscher hypothesized that in untrained overweight/ obese subjects with little experience in exercise, RES training would be unable to induce the specific adaptations characteristic of this exercise modality, and that this, in turn, might explain why the results of AER and RES training were similar.We agree that, in untrained subjects, there may be some overlap between the effects of AER and RES training, and that the fullblown effects of these different exercise modalities can be only appreciated when sustained high-intensity training is performed, as occurs in athletes. Nonetheless, the latter would not be an appropriate model for assessing the effects of these training modalities on hepatic fat accumulation of sedentary subjects with type 2 diabetes, which was the aim of our study.…”

Does mild resistance training resemble a similar stimulus compared to aerobic training?

“…Nonalcoholic fatty liver disease (NAFLD) is now becoming the most common liver disease in the world 2 and Bacchi et al 1 were able to demonstrate that exercise per se is effective in decreasing hepatic fat content and improving hepatic steatosis of adults suffering from type 2 diabetes and NAFLD. The data provide an important contribution to the highly relevant "exercise is medicine" paradigm, which further gains ground by evidence presented in the work of Bacchi et al 1 In our opinion, however, it would be important to match energy expenditure of both interventions.…”