HOP llMlNG OF SPLlT STEP AND KINETICS ANALYSIS OF LOWER EXTREMITIES IN BADMINTON START FOOTWORK

The purpose of this study was to compare the split timing, and lower extremity kinetics of badminton players during push-off steps in six directions. Eight collegiate elite male badminton players received the random shot from an opponent in one of six directions. Result: Hop timing was 0.014-0.037 sec after the opponent struck the shuttlecock. The leg that was opposite the movement direction showed significantly greater tower extremity horizontal push-off force than the other leg did. Conclusion: The hop timing of split step simultaneous with the opponent striking the shuttlecock. The leg opposite the movement direction was the main push leg. When lower extremities exhibit the correct pushing direction and reach the peak push off force within 0.3 sec after the opponent strikes the shuttlecock, players should have more effective return in badminton

BIOMECHANICAL ANALYSIS OF BADMINTON FOREHAND NET SHOTS

The purpose of this study was to compare the upper extremity kinematics variables of badminton forehand dab shot, stab shot and cross court net shot. The participants were eight elite collegiate male players in Taiwan. The kinematical data were collected by Vicon system (250Hz) and the Visual 3D software was used to analyze the variables. The results indicated that the elite badminton players perfomed dab net shot with less angular velocity in racket upper limb joints. They performed the stab net shot with faster angular velocity in forearm supination and wrist ulnar flexion. The cross court net shot had greatest angular velocity in shoulder internal rotation, forearm pronation and the least distance between the contact point and the mid-line of body

BIOMECHANICAL ANALYSIS OF BADMINTON DIFFERENT FORWARD STEPS

The purpose of this study was to compare the biomechanical variables between 2-step and 3-step forward steps in badminton. Eight collegiate elite male badminton players participated in this study. Eight Vicon T-20 cameras (300 Hz) were used to record the 3D kinematics data and a Kistler force plate (1500 Hz) was used to collect the GRF data of the last steps. A Wilcoxon matched-pairs signed-rank nonparametric statistical test was conducted to compare the differences between two kinds of forward step movements. The results showed that the movement time for 3-step movement was significantly faster than 2-step. We recommend that the badminton players should practice 3-step forward footwork technique. The additional strength and power training for lower limbs should be carried out for the footwork training

KINEMATICAL ANALYSIS OF TWO DIFFERENT FOREHAND BADMINTON DROP SHOTS TECHNIQUES

The purpose of this study was to compare the kinematics variables between badminton forehand regular and reverse slice drop shots. The participants were eight elite male players. Eight Vicon Motion T20s System cameras (300Hz) were used to record the 3D kinematic data, which were computed by Visual 3D software. All the variables were tested by Wilcoxon rank analysis of variance nonparametric statistical test with the significant level at a = .05. The results showed that there was significant difference between the two forehand drop shots in the racket pan angle. The strategy of two drop shots seems different. That might because the reverse slice drop was with greater shoulder abduction movement than the regular drop shot. The players performed reverse slice drop shot might because that the abduction movement was similar with the smash

THE DYNAMICAL ANALYSIS OF TABLE TENNIS FOREHAND AND BACKHAND DRIVES

The purpose of this study was to analyze the dynamics parameters of table tennis drives by Taiwan collegiate first class table tennis players when they were performing straight and cross court forehand and backhand drives from receiving topspin and backspin serves. Ten Vicon MX-13+ high-speed cameras (250Hz) and two Kistler force plates (1500 Hz) were used to collect the kinematics and kinetics data. The Wilcoxon matched-pairs signed-rank nonparametric statistical test was to compare the differences between forehand and backhand drives. The results showed that there were significant differences between forehand and backhand drives were in the ball initial velocity and the kinetics variables. The GRF data of the players were different between forehand and backhand drives when they performed four different paths of drive

THE UPPER LIMB EMG ACTIVITY COMPARISON OF DIFFERENT TABLE TENNIS FOREHAND DRIVES

The purpose of this study was to combine dynamics and surface EMG methods to analyze the movements of table tennis forehand drives by Taiwan elite table tennis players performing straight and cross court forehand drives from topspin and backspin serves. The kinematical data were collected by 10 Vicon MX13+ high-speed cameras and one Biovision system was used to record the EMG signal of seven muscles groups on the dominate hand. The results showed that there were significant differences among the four table tennis drives. The players exerted greater muscular activity in the wrist extensors, the biceps and the triceps for the backspin serve forehand drive than when returning the topspin serve forehand drive, not only on the straight but also on the cross court strokes

Is having asthma associated with an increased risk of dying from cardiovascular disease?:A prospective cohort study of 446 346 Taiwanese adults

Objectives A significant proportion of cardiovascular disease (CVD) cannot be explained by well-known risk factors such as high cholesterol, hypertension and diabetes. One potential novel risk factor for CVD is asthma. We aimed to investigate the association between asthma and mortality due to CVD. Design Prospective cohort study. Setting A large health check-up programme from 1994 to 2011 in Taipei, Taiwan. Participants 446 346 Taiwanese adults. Each participant answered questions regarding asthma history (yes/no) and current daily use of asthma medications (yes/no). Active asthma was defined as those using current daily medications for asthma. Outcomes The participants were followed for mortality from CVD, coronary heart disease (CHD) and stroke obtained through linkage to the cause-of-death register until 31 December 2011. Results We found an increased risk of dying from CVD in individuals with active asthma (adjusted HR (aHR) 1.32, 95% CI 1.08 to 1.62). The risk of death from CHD or stroke was increased in a similar manner (aHR 1.16, 95% CI 0.78 to 1.73 and aHR 1.23, 95% CI 0.86 to 1.74, respectively) although the HR estimates were less precise than that of CVD. For deaths from CVD, CHD and stroke, we found stronger associations with active asthma than non-active asthma, and for CVD and stroke stronger associations in men than women. Conclusion Our study suggests that asthma, particularly active asthma, may be associated with adverse cardiovascular consequences