Diet or Exercise for losing weight. What`s more effective?

Diet or Exercise for losing weight. What`s more effective?

Often people wonder what is best or more effective for losing weight, to make a diet or exercise ? Also, for different reasons, e.g. lack of time, some people choose only the one of these two alternatives and that way they don`t have the best results. However, both diet and exercise, if they are done properly of course, are effective means of reducing the body weight.


The diet gives negative energy balance (calorie reduction) resulting in rapid weight loss and when it is balanced, it gives euphoria and can prevent health problems which are associated with obesity. On the other hand, it may cause a small reduction in muscle mass and resting energy expenditure (the calories that are burned when the body is at rest). Furthermore, the proper keeping of a diet program, often depends on the intrinsic motivation of each person, his/her psychology and in general from his/her daily routine.


Exercise causes weight loss at a slower pace or requires a great effort in order to achieve a similar result to that if you are making a diet. For example, in order to lose a pound in a week just by increasing energy expenditure (exercise), someone who weights 80kg should walk for 110 minutes or ride the bicycle for 80 minutes or swim for 45 minutes, on a daily basis, in addition to his/her daily activity. Moreover, when the total intake of calories covers the ones who have been burned from the exercise, then it may be no loss. If for example the daily needs of a person is 2000 calories and with exercise he/she burns 500 calories, but consumes 2500 calories or more, the calories that have been burned, are replenished. The exercise achieves maintaining or increasing the muscle mass and prevents the decrease of energy rest expenditure.

What is better to choose then, diet or exercise ? From the above, we can conclude that both diet and exercise have advantages and disadvantages. It seems though that the advantages of the one outweigh the disadvantages of the other. According to the following:

  • When the exercise is being added to a diet, the loss of muscle mass can be significantly reduced. It seems that when resistance training is being added to the general program of activity, then it can greatly help to maintain the muscle mass. For example, the weight loss through diet (by removing calories at ease) corresponds to approximately 75% loss of fat and 25% loss of muscle mass. The combination of diet and exercise can reduce the loss of muscle mass to 5%.
  • Exercise can act like a psychological catalyst in the effort of losing weight. When the diet is accompanied by exercise, people are in a better mood, have self-esteem and so they can more easily to improve their eating habits.
  • A moderate diet (by removing calories at an ease) in combination with exercise, both aerobic and resistance training, reduces significantly the weight and consequently the fat. For example, if there is a daily calorie reduction in combination with energy consumption (calorie consumption) due to exercise, someone can manage to lose even twice the weight loss. A mild calorie reduction can be easily achieved by reducing fat and sugar, together with feeding behaviour modification techniques by a dietician.
  • Even when the targeted weight loss is achieved, when the exercise continues, the person can more easily maintain his/her weight. Studies have shown that daily exercise which gives 10 calories per kilogram of body weight (e.g. 50kg * 10kcal = 500kcal) is more effective in maintain the weight. It should be also noted here that after the end of a diet, the exercise should be accompanied by a balanced diet, according to the needs and habits of every person.

In conclusion, in the question diet or exercise , the answer is that a comprehensive weight loss program that combines a balanced diet and exercise, together with specific modification techniques of dietary behaviour, always by specialized health professionals (trainer, dietician or psychologist) contributes significantly to the success of weight loss.


  1. Stiegler P1Cunliffe A. The role of diet and exercise for the maintenance of fat-free mass and resting metabolic rate during weight loss. Sports Med. 2006;36(3):239-62.
  2. Ramage S1Farmer AApps Eccles KMc Cargar L. Healthy strategies for successful weight loss and weight maintenance: a systematic review. Appl Physiol Nutr Metab. 2014 Jan;39(1):1-20. doi: 10.1139/apnm-2013-0026. Epub 2013 Nov 4.
  3. Garfinkel. P., and Coscina, D. 1990. Discussion: Exercise and obesity. In exercise, fitness, and Health, eds.C
  4. Schoeller DA1Shay KKushner RF. How much physical activity is needed to minimize weight gain in previously obese women? Am J Clin Nutr. 1997  Sep;66(3):551-6.
  5. Daniel R. Bensimhon, MD, William E. Kraus, MD, and Mark P. Donahue, MD Durham, NC. Obesity and physical activity: A review. Am Heart J 2006;151:598-603.)



Be the first to comment

Leave a Reply

Your email address will not be published.