Two Weeks of Exercise Training Intensity on Appetite Regulation in Obese Adults with Prediabetes.

PURPOSE: No short-term exercise data exist testing whether training intensity modifies hormonal and perceived appetite in obese adults with prediabetes. Therefore, we compared the effects of short-term moderate continuous (CONT) vs. high-intensity interval (INT) training on appetite regulation.

METHODS: Twenty-eight obese adults (Age: 61.3±1.5yr; BMI: 33.2±1.1) with prediabetes were randomized to work-matched CONT (n=14) or INT (n=14) training for 2 weeks. Plasma acylated ghrelin (AG), des-acylated ghrelin (dAG), active glucagon-like peptide-1 (GLP-1) and insulin were measured at 0, 30 and 60min of a 75g OGTT before and after training. Visual Analog Scales were administered at 0 and 120min during the OGTT to examine perceived appetite. Three-day food logs were collected pre- and post-testing to assess ad libitum diet.

RESULTS: CONT and INT increased VO2 peak ( P<0.01) and decreased BMI ( P<0.01). Although neither intervention altered fasting levels of AG ( P=0.94), dAG ( P=0.36), or insulin ( P=0.67), CONT exercise raised GLP-1 compared to INT ( P=0.05). Exercise training did not affect post-prandial suppression of AG ( P=0.81) and dAG ( P=0.67) or stimulation of GLP-1 ( P=0.67) and insulin ( P=0.32). Both interventions tended to decrease total energy and protein intake ( P=0.09 and P=0.05, respectively), despite no change in fasting hunger ( P=0.88) and reduced perceived fullness at 120min during the OGTT ( P=0.05).

CONCLUSION: Two weeks of exercise training intensity does not modulate appetite regulatory hormones in obese adults with prediabetes. Although perceived fullness to the OGTT was reduced following exercise, CONT and INT decreased energy intake, suggesting that exercise does not elicit compensatory appetite behavior to gain weight.