ABSTRACT
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/m2) 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/m2) 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: STS 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 task can be used in the design of future trials to assess the efficacy of rehabilitative treatment.
Subject(s)
Back Pain/physiopathology , Movement/physiology , Muscles/physiology , Obesity/physiopathology , Adult , Ankle Joint/physiology , Back Pain/complications , Back Pain/rehabilitation , Biomechanical Phenomena , Case-Control Studies , Chronic Disease , Cross-Sectional Studies , Female , Hip Joint/physiology , Humans , Knee Joint/physiology , Male , Middle Aged , Obesity/complications , Obesity/rehabilitation , Posture , Weight-BearingABSTRACT
The fine structure of gastric epithelial cells of normal rats and of rats restrained at low temperature has been examined by transmission and scanning electron microscopy. The observation of the normal mucosa has revealed that in comparison with the cells overlying the flat surface of the stomach, those covering the plicae have a different surface structure with numerous microvilli and a peculiar organization of intercellular junctions. Restrained animals initially showed swelling of the foveolae that was followed by a detachment of the superficial cells leading to severe stomach erosions. It is postulated that the first modification induced by stress is a decrease in the amount of mucus granules and a weakness of the mucous protective barrier. This was confirmed by the results obtained by pretreating rats with zolimidine. This substance, which has been shown to increase secretion and synthesis of gastric mucus, completely protected the animals from the stress-induced damage of the stomach surface. Furthermore, this treatment produced an enlargement of the cisternae of the endoplasmic reticulum and an increase in the surface of the Golgi apparatus in the epithelial cells.
