Effects of exercise on gut peptides, energy intake and appetite

Abstract

This study investigated the acute effects of exercise on the postprandial levels of appetite-related hormones and metabolites, energy intake (EI) and subjective measures of appetite. Ghrelin, polypeptide YY (PYY), glucagon-like peptide-1 (GLP-1) and pancreatic polypeptide (PP) were measured in the fasting state and postprandially in 12 healthy, normalweight volunteers (six males and six females) using a randomised crossover design. One hour after a standardised breakfast, subjects either cycled for 60 min at 65% of their maximal heart rate or rested. Subjective appetite was assessed throughout the study using visual analogue scales and subsequent EI at a buffet meal was measured at the end (3-h post-breakfast and 1-h post-exercise). Exercise significantly increased mean PYY, GLP-1 and PP levels, and this effect was maintained during the post-exercise period for GLP-1 and PP. No significant effect of exercise was observed on postprandial levels of ghrelin. During the exercise period, hunger scores were significantly decreased; however, this effect disappeared in the post-exercise period. Exercise significantly increased subsequent absolute EI, but produced a significant decrease in relative EI after accounting for the energy expended during exercise. Hunger scores and PYY, GLP-1 and PP levels showed an inverse temporal pattern during the 1-h exercise/control intervention. In conclusion, acute exercise, of moderate intensity, temporarily decreased hunger sensations and was able to produce a short-term negative energy balance. This impact on appetite and subsequent energy homeostasis was not explained by changes in postprandial levels of ghrelin; however, 'exercise-induced anorexia' may potentially be linked to increased PYY, GLP-1 and PP levels.

Is it fun or exercise? The framing of physical activity biases subsequent snacking

“…Preference for luxuries, relative to utilities, is also enhanced by previous acts enhancing self-concept, such as donations to charity (Khan and Dhar 2006). Previous research on compensation between exercising and food consumption suggests that physical activity can have a similar licensing effect allowing individuals to increase subsequent energy intake (e.g., Martins et al 2007). Indeed, mental effort (Chaput et al 2008) and even imagined exercising may lead to increases in food consumption (Werle et al 2011).…”

“…compensation for physical excursion expended (King 1999;King et al 1996;Martins et al 2007) and overestimate calories burned relative to the calories consumed (Lichtman et al 1992;Wansink and Chandon 2006). To understand how to attenuate this compensation, we examined how changing perceptions of physical activity through framing can impact subsequent food consumption.…”

Influence of resistance and aerobic exercise on hunger, circulating levels of acylated ghrelin, and peptide YY in healthy males

“…The majority of studies have focused on aerobic (cardiovascular) exercise (31), with only three studies examining the effects of resistance (muscle strengthening) exercise, and these have reported contradictory effects (21,33,47). Resistance exercise is a key component of exercise recommendations for weight control (2) and public health (23, 42); thus, it is important to clarify the effects of resistance exercise on hunger and gut hormones.The effect of acute exercise bouts on total plasma ghrelin concentrations is controversial, with studies reporting no changes either during or postexercise (10,15,26,27,32,39,43,45,47), as well as increases (14,17,25,44) and decreases (21,33,48,50). Acylation of ghrelin is thought to be essential for appetite regulation because only the acylated form of the hormone can cross the blood-brain barrier (41).…”

“…The effect of acute exercise bouts on total plasma ghrelin concentrations is controversial, with studies reporting no changes either during or postexercise (10,15,26,27,32,39,43,45,47), as well as increases (14,17,25,44) and decreases (21,33,48,50). Acylation of ghrelin is thought to be essential for appetite regulation because only the acylated form of the hormone can cross the blood-brain barrier (41).…”

“…There are two main circulating forms of PYY, PYY and PYY (11); both have been shown to reduce food intake when administered peripherally (13); however, PYY is more potent than PYY . Only one study has investigated the response of PYY to an acute bout of exercise (39). In this study, subjects consumed a standardized breakfast and 1 h later cycled for 60 min at 65% of their maximal heart rate.…”