In addition to the basal metabolic rate, the energy expenditure is added for every further performance a human accomplishes, whether it is muscle activity or concentrated brain work. For light work, these are 0.5–1 kcal per kg body weight and hour, for medium work 1–2 kcal, for heavy work 2–12 kcal, and for very hard work significantly more than 12 kcal. In everyday life, these evaluations find their way into the recommendations of the German Nutrition Society. They specify the daily calorie intake depending on the muscle work. For example, these guideline values are 2100 kcal per day for women and 2700 kcal for men, respectively, for the age between 25 and 50 years (Table 10.1). Middle physical activities such as those of housewives, waiters or craftsmen serve as comparison values.

Table 10.1 Recommended values for daily energy intake with a normal BMI and moderate physical activity (

If you also exercise regularly in your free time, you will increase your calorie consumption. The additional consumption often takes considerable proportions, as the data of some professional athletes and sportswomen show. For them, time can often become a limiting factor when it comes to consuming the necessary large amounts of food, especially since great efforts often have an appetite-reducing effect on the following 1–2 h. This peculiarity affects, for example, participants in the big road cycling races. Today’s energy-rich drinks help a lot with coping with this special problem.