Differential effects of endurance training and weight loss on plasma adiponectin multimers and adipose tissue macrophages in younger, moderately overweight men

Obese individuals are characterized by low circulating adiponectin concentrations and an increased number of macrophages in adipose tissue, which is believed to be causally associated with chronic low-grade inflammation and insulin resistance. Regular physical exercise decreases overall morbidity in obese subjects, which may be due to modulations of inflammatory pathways. In this randomized clinical trial we investigated the separate effects of endurance training-induced weight loss, diet-induced weight loss, and endurance training per se (without weight loss) on plasma adiponectin multimer composition (Western blotting) and adipose tissue macrophage content (immunohistochemistry) in young, moderately overweight men. Weight loss and endurance training per se decreased whole body fat percentage in an additive manner. No intervention-induced changes were observed for plasma total adiponectin. Surprisingly, endurance training, irrespectively of any associated weight loss, shifted the adiponectin multimer distribution toward a lower molecular weight (21% decrease in HMW/LMW, P = 0.015), whereas diet-induced weight loss shifted the distribution toward a higher molecular weight (42% increase in HMW/MMW, P