Sit-to-stand movement analysis in obese subjects

OBJECTIVES: The aim of this study was to evaluate the typical strategies of obese subjects during a sit-to-stand task (a typical daily living activity) and to assess the load conditions of hip, knee and ankle joints. DESIGN: Cross-sectional, controlled (obese patients vs controls) study on sit-to-stand movement analysis SUBJECTS: Ten adult young volunteers (five men and five women, mean age 28, s.d, 3 y; mean BMI 22, s.d. 2.3 kg/m(2)) and 30 obese subjects 25 women and five men, mean age 39.4, s.d. 13.7 y, mean BMI 40, s.d. 5.9 kg/m(2)) suffering from chronic lower back pain were analyzed in a sit-to-stand task (10 trials for each subject). MEASUREMENTS: Angle parameters carried out from a quantitative three-dimensional analysis of sit-to-stand (STS) movement, using an optoelectronic system. RESULTS: SIS task in controls was characterized by a fully forward bending strategy of the trunk, while in obese patients at the beginning (first trial) of the STS task they limited the forward bending in order to protect the vertebral column. When fatigue increased during the execution of multiple STS tasks, the protection of the vertebral column was secondary to the execution of the task. In order to limit the muscle fatigue they increased the forward bending in order to decrease knee joint torque. DISCUSSION: The analysis of the strategy used by obese patients in STS tasle can be used in the design of future trials to assess the efficacy of rehabilitative treatment.