RÉSUMÉ
Hamstring strain injury (HSI) is one of the most common injuries in athletes, which seriously reduces the mechanical properties of the muscles and affects the performance of the athletes. If not fully recovered, it will lead to secondary hamstring injuries and even permanent functional deficits. Therefore, prevention of HSI is particularly important. At present, the prevention strategies of HSI at home and abroad mainly focus on strength training, but high-intensity strength training can easily lead to muscle and joint injuries. By contrast, pliability training is a better choice for HSI prevention, for it involves stretching, joint movement and circuit training, etc, which can improve muscle extensibility, with lower intensity and higher safety than centrifugal strength training. In sports practice and clinical application, there are many problems such as inappropriate training volume, incomplete programs or poor effect, due to a lack of sufficient knowledge of pliability training in the prevention of HIS and a unified standard for training programs. For this purpose, the authors reviewed the effects of pliability training on the function and sports performance of hamstring muscles and its application in the prevention of HIS so as to provide reference for the effective prevention of HSI.
RÉSUMÉ
BACKGROUND:Osteoporosis is increasingly threatening the elderly survival quality and life. Numerous studies have shown that the vibration training is a new method to improve osteoporosis. OBJECTIVE:To overview the effect of vibration training on the skeletal system, and provide a new idea for osteoporosis prevention. METHODS:The first author searched the PubMed and CNKI databases using the fol owing format:(Vibration training [Title]) OR (Vibration mode [Title]) OR (Vibration pattern [Title]) and (“Vibration training”[Title]) or (“Vibration mode”[Title]) in English and Chinese, respectively, in April 2015. Final y, 38 eligible articles were included according to their titles and abstracts. RESULTS AND CONCLUSION:Bases on overseas and domestic researches about the effect of whole body vibration on the skeletal system, we summarize the mechanical load, vibration stress principles and outcomes of whole body vibration training as wel as factors involvied in osteoporosis such as the stimulation site, stimulation type, exercise load, exercise duration and vibration frequency. In addition, the safety of vibration training and its preceding studies are also generalized. These results suggest that elderly osteoporosis can be improved through the vibratory equipment. We can improve bone loss and living quality of the elderly by vibration at different frequencies and duration thresholds vibration at using the vibratory equipment.
RÉSUMÉ
BACKGROUND:At present, the detections of muscular strength of the main joints in shot putters by using isokinetic system are rarely reported. OBJECTIVE:To find out the characteristics of muscular strength of the main joints in shot putters under different speed, and explore the existing shortcomings. METHODS:Using German ISOMED2000 isokinetic test system, we detected the isokinetic muscular strength of knee joint, hip joint, waist-back segment, and shoulder joint of the men’s shot put champion in the 11th Games, at slow 60°/s and fast 180°/s. RESULTS AND CONCLUSION:(1) H/Q ratios of the left and right side of knee joint were 25.6%, 39.4%in slow speed, while 28.5%, 29.8%in high speed. In addition, flexor muscle group had smal muscular strength. (2) The muscular strength of the right extensor group of hip joint was as much 2.11 and 1.87 times respectively as left side in high and slow speed. Meanwhile, flexor muscle group was 1.25 and 1.64 times and significance of right hip was greater than the left. (3) H/Q ratios of the waist and back joints were 93.3%and 84.3%respectively in high and low speed. (4) Under natural flexion of shoulder joint, myodynamia flexion in slow speed was as much 1.27 and 1.34 times respectively as the left, while 1.40 and 1.92 times respectively as the left in fast speed. (5) According to relative weight of the human body model, when each segment was compared to knee as a benchmark, the knees, hips, body and shoulder joints were 1:2.38:3.30:0.70. The findings indicate that, (1) in the knees joint, not only absolute myodynamia of flexor and extensor groups, but also myodynamia of fast flexor groups are weak, the equipment of myodynamia group is not reasonable as wel . (2) The body myodynamia reaches the peak in the right side of extensor group, while rapid extensor myodynamia at the left and right side is very weak, therefore, we should increase the training of waist and back extensor, especial y muscle strength training and extension training at the slow and high speed. (3) As extensor group on the right side is weak, we should strengthen the absolute extensor group muscle power of right shoulder and absolute muscle strength of flexion muscle group.