The effect of breakfast consumption prior to exercise on cognitive performance, mood and appetite

Abstract

Exercise can improve mood and some facets of cognitive performance acutely and may suppress appetite transiently. Breakfast consumption is associated with mood and memory enhancement and superior control of appetite and body weight. Beneficial pre-exercise nutritional practices for those who exercise for mood, cognitive and appetite benefits, rather than to improve physical performance, have not been well established. Therefore, the current PhD programme aimed to uncover the potential effects of breakfast consumption prior to exercising on cognitive function, mood and appetite later in the day, with a particular focus on recreationally active females, an under-represented population in this area of research. The results from two intervention studies presented in this thesis determined that consuming, compared to omitting, breakfast prior to exercise reduced appetite until the next meal was consumed and abridged mental fatigue in the post-exercise recovery period in active males (Chapter 2) and females (Chapter 5). Active females may choose to undertake morning exercise in a fasted state to avoid discomfort during exercise and due to lack of time (Chapter 3), but postexercise, overall mood positively correlated, and mental fatigue inversely correlated with breakfast size prior to exercise in active females when assessed in a field setting (Chapter 4); however, consuming a lower energy dense breakfast still elicited the aforementioned positive effects, and was preferential to consuming a larger breakfast to avoid cognitive detriments in the afternoon when measured in a laboratory setting (Chapter 5). To conclude, the results from this thesis suggest that consuming breakfast prior to morning exercise is beneficial for post-exercise mood and appetite in both habitually active men and women, but consuming a large breakfast may impair cognitive function after exercise. Consuming a light breakfast pre-exercise may be a particularly beneficial practice for habitual female exercisers who chose to omit breakfast prior to exercise due to lack of time or to avoid discomfort during exercise