Does Exercise Make Us Hungry?
There has been much debate about the effect of exercise on appetite and energy intake. Although some scientists have proposed that exercise stimulates appetite; most studies do not support this finding.
A recent study published in Medicine & Science in Sports & Exercise4 examined the effect of walking on appetite and food intake. In the study, subjects participated in two different trials – an exercise and a nonexercise (control) trial. One day subjects walked for 60 minutes on a treadmill with some mild shortness of breath but were still able to hold a conversation. On another day, they came to the lab at the same time of day but did not exercise (control trial). Subjects were offered an “all you can eat” buffet style meal two hours after exercise and again at five hours after exercise. When subjects did not exercise they were offered the same buffet meal at the same time of day. Subjects also rated their appetite every 30 minutes.
The results showed that after a 60-minute brisk walk subjects did not increase the amount of food they ate for the next seven hours compared to the control trial. In fact, exercising subjects had a 439 calorie deficit after accounting for the amount of food consumed. There was also no difference in the fat or carbohydrate content of meals on the exercise vs. nonexercise days. Researchers also measured levels of a hormone (ghrelin) produced in the stomach which is known to increase hunger. They found no difference in the hormone levels or ratings of appetite on the exercise compared to nonexercise trials.
This study supports the findings of other researchers1 that moderate intensity exercise does not increase appetite. With regard to high intensity aerobic exercise, studies2,3 tend to show that appetite is suppressed for a brief period after 60 minutes of treadmill running. Another study2 also reported a brief suppression of appetite after 90 minutes of resistance training.
Dieting alone to lose weight can be brutal. So why not go for a bigger calorie deficit by adding exercise to your diet program. Exercise yields lots of health benefits like improvements in blood pressure, cholesterol, and blood sugar levels. Plus, exercisers have lower all-cause death rates. It's time to get moving!
1. Blundell, J.D., and King, N.A. (2000). Exercise, appetite control, and energy balance. Nutrition, 16(7-8), 519-522.
2. Broom, D.R., Batterham, R.L., King, J.A., Stensel, D.J., Batterham, F.L., and King, J.A. (2009). Influence of resistance and aerobic exercise on hunger, circulating levels of acylated ghrelin, and peptide YY in healthy males. Am J Physiol Regul Integr Comp Physiol, 296(1), 29-35.
3. Broom, D.R., Stensel, D.J., Bishop, N.C., Burns, S.F., and Miyashita, M. (2007). Exercise-induced suppression of acylated ghrelin in humans. J Appl Physiol, 102(6), 2165-71.
4. King, James A., Wasse, L.K. Broom, D.R., and Stensel, D.J.. (2010) Influence of brisk walking on appetite, energy intake, and plasma acylated grehlin. Med & Sci in Sports & Exerc, 42(3), 485-492.