Sitting time increases the overweight and obesity risk independently of walking time in elderly people from Spain

Introduction: Obesity, defined as an excess of total body fat, is a matter of concern all over the world, and its prevalence is still increasing among elderly people.

Objectives: To examine whether sedentary behaviour (hours sitting per day) is associated with higher risk of central obesity, overweight-obesity and overfat in a representative sample of non-institutionalized Spanish elderly population and if so, whether hours walking per day modified this association.

Study design: A cross-sectional study in a sample of 3136 people ≥65 years of age.

Main outcomes measures: Anthropometric measurements were obtained using standardized techniques and equipment. Active and sedentary behaviours were recorded by questionnaire.

Results: For both men and women, the higher prevalence of overweight-obesity, central obesity and overfat was found in those who spent sitting more than 4h per day and walk less than 1h, compared with those who spent sitting less than 4h per day and walk more than 1h (all p<0.001, except for central obesity in women). In men, more than 4h sitting per day was associated with 1.7-fold higher odds of having central obesity compared with those sitting less than 4h per day (p<0.01). In women, this sedentary behaviour increased the risk of overweight-obesity and overfat by 1.5 and 1.4, respectively (p<0.01). Age or time spent walking did not significantly change these results.

Conclusion: Sitting time increases the risk of overweight-obesity and overfat in women and the risk of central obesity in men, independently of walking time.