Acute Reversal of the Enhanced Insulin Action in Trained Athletes: Association with Insulin Receptor Changes

Abstract

We studied the effect of aerobic training and detraining on insulin-stimulated glucose disposal and on erythrocyte insulin receptor binding. Seven endurance-trained athletes were studied at 12 h, 60 h, and 7 days after cessation of training and compared with three untrained, age- and weight-matched controls. The metabolic clearance rate of glucose as measured by the euglycemic clamp technique was 15.6 +/- 1.8 ml/kg/min (mean +/- SEM) in the trained subjects 12 h after the last bout of exercise compared with 7.8 +/- 1.2 ml/kg/min in the untrained control group. When the trained subjects refrained from physical training, the metabolic clearance rate decreased to 10.1 +/- 1.0 ml/kg/min at 60 h and further to 8.5 +/- 0.5 ml/kg/min after 7 days of detraining. The percentage of specific insulin binding to young erythrocytes (density 1.089-1.092), isolated by density gradient centrifugation, decreased from 10.4 +/- 0.9 at 12 h after the last exercise to 8.1 +/- 0.7%/3 X 10(9) cells after 60 h of detraining (P less than 0.001). The decrease in insulin binding to erythrocytes was almost entirely accounted for by a decrease in the number of insulin receptors. We conclude that the increase in peripheral insulin action seen in trained athletes is rapidly reversed, possibly by a mechanism separate from other phenomena associated with chronic training. The parallel findings of decreased in vivo insulin action and decreased insulin binding in young erythrocytes suggest that modulation of in vivo insulin response by detraining may be at least partially mediated by changes in insulin receptor number.(ABSTRACT TRUNCATED AT 250 WORDS)

Exercise and the metabolic syndrome

“…If exercise training is discontinued, the improvements gained in both insulin sensitivity and glucose tolerance will vanish within a few days. Improved insulin sensitivity has been demonstrated 12-48 h after the exercise bout, but is virtually unmeasurable 3-5 days after the last exercise session [109][110][111][112]. However, this can be rapidly regained by one single bout of exercise [109,113].…”

“…Improved insulin sensitivity has been demonstrated 12-48 h after the exercise bout, but is virtually unmeasurable 3-5 days after the last exercise session [109][110][111][112]. However, this can be rapidly regained by one single bout of exercise [109,113]. If physical exercise is minimal during leisure time, insulin sensitivity is low, and a few days bed rest is associated with substantial insulin resistance [114].…”

Early-onset type 2 diabetes in obese white subjects is characterised by a marked defect in beta cell insulin secretion, severe insulin resistance and a lack of response to aerobic exercise training

“…These improvements, while impressive, are likely to be proportional to the duration and intensity of the exercise regime [16]. The metabolic benefits of exercise are known to be short-lived [17][18][19][20]. This has important implications for the design and optimisation of exercise interventions.…”

Análise da percepçãp dos diabéticos tipo 2 sobre a doença e o tratamento

“…Esse resultado corrobora apenas com um estudo realizado em 2011, o qual mostra que um quinto dos entrevistados praticava pelo menos uma vez o exercício físico como prática do lazer (caminhada). 21 Outro estudo efetuado em 2009 obteve resultados diferentes do presente estudo, onde se encontrou uma inatividade física superior a 54%, essa falta de aderência está relacionada de maneira proporcional ao aumento da idade e do menor nível de escolaridade e condições socioeconômicas. 19 Em relação ao deslocamento do dia a dia, 67% se deslocam por meio de ônibus e 27% a pé.…”