BACKGROUND:Obesity negatively affects dynamic balance during walking,and crossing barriers is a more routine functional activity that requires more stability in controlling body posture. OBJECTIVE:To investigate the differences in dynamic stability between obese and average males,and to assess the balance ability of obese males using a relatively more challenging obstacle crossing. METHODS:A total of 24 male youths(12 each in the obese and normal groups)were recruited to complete the tests of walking on level ground and crossing obstacles of different heights(4 cm,11 cm,15 cm)in random order.Kinematic and dynamic data were collected using the Qualisys motion capture system and Kistler force stage.Statistical analysis was performed using two-factor(2 groups * 4 movement types)repeated measures analysis of variance. RESULTS AND CONCLUSION:The obese group had a lower step speed than the normal group(P<0.05),the proportion of the first single support period decreased and the proportion of the second double support period increased when crossing the 11 cm versus 15 cm hurdles(P<0.05).When walking on level ground,the margin of stability in the internal and external directions in the normal group was greater than that of the obese group(P<0.05).When crossing the 4 cm hurdles,the margin of stability in the obese group was less than that in the normal group(P<0.05).When crossing the 11 cm hurdles,there was no significant difference between the two groups in the anterior-posterior direction(P>0.05),while there was a significant difference in the internal-external direction(P<0.05).When crossing the 15 cm hurdles,the margin of stability in the obese group was lower than that in the normal group(P<0.05).Overall,obesity decreases the body's ability to control the body,reduces dynamic stability during crossing the barrier,and increases the risk of falls compared with the general population.In addition,compared with level ground walking,the decrease in the dynamic stability when crossing barriers is more significant in the obese group than the general population.

Dual-task diagram focuses on the interaction between cognition and motor control, and has been applied in falls predictor and training in old people. It was found that dual-task diagram is a more sensitive and useful method than gait test to predict the risk of falls in the older people, especially for those with central nervous system disease. The dual-task training can improve the cognitive and physical abilities of the older adults, but it is argued that combined cognitive and physical exercise is more beneficial than either one individually.

Objective To investigate the effects of shoes type (barefoot, ordinary running shoes, minimalist shoes) and walking speed (jogging, walking at normal speed) on biomechanical parameters of knee joint, so as to provide theoretical reference for scientific fitness. Methods Vicon three-dimensional （3D） motion capture system and Kistler 3D force plate were used to collect biomechanical parameters of lower limbs from 10 subjects during walking at different speed with different shoes. Two-way (2 walking conditions × 3 shoe conditions) repeated measures analysis of variance was used to statistically analyze each dependent variable. Results Compared with jogging, the lateral excursion of plantar center of pressure (COP) was greater, the moment arm in frontal plane, the adduction moment and peak loading rate of knee joint were smaller, but the angular impulse of knee joint in frontal plane was greater. Compared with ordinary running shoes, the stride length was decreased, the lateral excursion of COP was greater, and the moment arm of knee joint in frontal plane, the knee adduction moment, the peak load rate and the angular impulse of knee joint in frontal plane were smaller. Conclusions In order to reduce the angular impulse and peak loading rate of knee joint in frontal plane, it is recommended to jog with small strides for ordinary people with minimalist footwear.

Through providing rhythmic stimulation to movement center, rhythmic auditory stimulation (RAS) may encourage hemiplegic patients to adjust movement pattern and external rhythm in time to improve the walking function after stroke. As an emerging intervention to treat the hemiplegic patients after stroke, RAS could effectively improve temporospatial gait parameters (gait velocity, stride length, cadence, and symmetry, etc.), joint movement pattern (angle of pelvis anterior tilt, and peak angle of knee flexion in mid-swing, etc.) and balance, which may be related to rhythmic entrainment movement system and the theory of auditory-movement synchronization. Simultaneously, frequency and dosage of RAS and the patient's lesions all have effect on the outcome of intervention.