[Body weight and physical activity: how much is too little? How much is enough?--a study in recreational cyclists]

Body weight and body mass index (BMI) were studied in non professional cyclists. BMI increased from 22.2 +/- 2.3 kg/m2 (20 to 29 y) to 23.8 +/- 1.7 kg/m2 (55 to 77 y) (mean +/- SD). The mean increase per decade was 0.5 kg/m2, markedly less than in the general Swiss population (0.8 to 1.0 kg/m2). Overweight (BMI 25.1-29.9 kg/m2) prevalence increased from 7.4% (20 to 29 y) to 25.5% (55 to 77 y) and obesity (BMI +/- 30.0 kg/m2) was rare (0.2%, n = 1). The amount of sport correlated negatively with BMI change. A high amount of moderate to heavy physical activity (five hours weekly) was required to avoid an increase in BMI. This amount is to high for the general population. Thus, control of energy intake should be advised together with physical activity.