The relationship between different body mass index categories and chair rise performance in adult women

An important prerequisite to carry out daily activities is the sit-to-stand movement. However, in obese people, this movement is characterized by altered biomechanics, which might lead to daily life activity impairments. The aim of this study was to investigate whether there are differences in kinetic and kinematic variables between three different BMI categories when performing a specific sit-to-stand test. Thirty-six adult women (BMI = 17-45 kg/m²) performed the sit-to stand test five times consecutively and as quickly as possible. Analyses of variance were used to determine differences between three BMI groups (normal or overweight: BMI < 30 kg/m²; obese: 30 ≤ BMI < 35; severely obese: BMI ≥ 35). Peak and mean vertical sacrum velocity indicated a decrease in severely obese subjects. Obese and severely obese individuals did not show higher fatigue over the five consecutive movements. Peak force and rate of force development decreased in normal or overweight subjects. The ability to successfully complete the test decreased with a higher BMI, probably due to a reduced ability to rapidly generate a high force.