Exercise indeed helps us feel good about ourselves. We release the feel good chemicals referred to as ‘endorphins’ while we also lower our stress hormone, referred to as ‘cortisol’! This can be dangerous for some of us particularly when after an hour’s workout at the gym you head directly to the cupboards or the fridge. Two hours later, having demolished half of the fridge and come to the realisation that you just couldn’t control yourself.
The relationship between exercise and weight loss is complex! This is especially the case when it has been an on-going issue. But did you know that not all exercise stimulates appetite to the same extent and each of us vary in how much weight we will lose from exercise.
So what do we do about it?
Latest research undertaken by Professor David Stensel and his team, of the School of Sport, Exercise and Health Sciences at Loughborough University, showed that the more intense and long the exercise, the more the levels of our ‘hunger hormone’ in the blood were suppressed.
This was small study of 16 healthy young men which looked into the effects of different types of exercise on the measured levels of the hunger hormone. The hunger hormone, also referred to as Ghrelin, is known to contribute to an increase in appetite. Standardised meals were provided to the men who were then asked to rate their hunger levels. The results showed that those who ran for 90 minutes still had lower levels of ghrelin an hour after exercise. In addition they felt less hungry for much longer. The study also found that more intense workouts reduced hormone levels at a greater extent than easy jogging. However the men still felt peckish a bit earlier than those who actually ran for longer
As Stensel, points out, whether exercise makes us want to eat more is a difficult area to research. This is because unless you directly watch what people do, you basically rely on them to self -report both the length and intensity of their exercise. This is also true to actually know how much they ate, relies on self-reporting which could sometimes be inaccurate.
But we know that if we want to lose weight it involves both the diet as well as exercise. According to David Broom, the lead author of the study and professor at the Academy of Sport and Physical Activity at Shellen Hallam University, we should exercise at a level above 75 % of our maximum heart rate for weight loss to be effective, while undertaking a healthy and balanced diet.
Broom acknowledges that to get round the small size of many clinical trials, his team pooled the data from the studies. The outcome was that the exercise must be at high intensity. Short bursts even as little as 30 second sprints, show to suppress Ghrelin and hence reduce appetite! That suppression of appetite can lasts approximately 2 hours and there is a variation that exists between individuals!
In summary, we know that the evidence shows that you will not feel hungrier or eat more at a subsequent meal necessarily. But being inactive, can lead to a greater likelihood of you putting on weight. Regardless of whether you want to lose weight or not, you should exercise for all the benefits that it confers to health. It not only lowers our blood pressure but also makes you happier!
BROOM, David, HOPKINS, Mark, STENSEL, D, KING, N and BLUNDELL, J (2014). The BASES expert statement on the effects of exercise on appetite control and energy intake. The Sport and Exercise Scientist, 41, 20-21.
KING, J.A., DEIGHTON, K, BROOM, David, WASSE, L.K., DOUGLAS, J.A., BURNS, S.F., CORDERY, P.A., PETHERICK, E.S., BATTERHAM, R.L., GOLTZ, F.R., THACKRAY, A.E., YATES, T and STENSEL, D.J. (2017). Individual variation in hunger, energy intake and ghrelin responses to acute exercise. Medicine and Science in Sports and Exercise, 49 (6), 1219-1228. Available at : http://shura.shu.ac.uk/14893/
NAWAL ALAJMI, KEVIN DEIGHTON, JAMES A. KING, ALVARO REISCHAK-OLIVEIRA, LUCY K. WASSE, JENNY JONES, RACHEL L. BATTERHAM, DAVID J. STENSEL. Appetite and Energy Intake Responses to Acute Energy Deficits in Females versus Males. Medicine & Science in Sports & Exercise, 2016; 48 (3): 412 DOI: 10.1249/MSS.0000000000000793