Improving lower extremity sports performance may contribute to punching performance in boxers. We compared the effects of two typical boxing routines for developing lower extremity sports performance and subsequent punching performance. Twenty-four high school amateur boxers between the ages of 12 and 18 performed training at least 3 days per week. All Athletes had 3–5 years of experience in boxing training. The participants separated into two groups to receive an 8-week plyometric or jump rope training program. They performed each training program for 30 min on 3 days/week. Lower extremity sports performance in countermovement jump (leg stiffness, jump power, and rate of force development) and jab-cross punching performance (punch velocity, punch force, reaction time, movement time, and ground reaction force) were assessed at pre-and post-training. The data were analyzed using a two-way mixed-design analysis of variance (ANOVA) (group × time). Both training programs improved the rate of force development in countermovement jump, the reaction time of punch, the peak ground reaction force of the rear leg during the jab punch, and the velocity of the jab punch. There were no group differences and interaction effects in all variables analyzed. It is concluded that 8 weeks of plyometric and rope jumping programs had a similar impact on improving lower extremity strength and punching performance. Both training programs may improve muscle strength and power, rate of force development, and reaction time. These improvements may contribute to lower extremity strength for driving a punch at the target with excellent performance.
1 December 2014 in Research in Developmental Disabilities
This study examined the effects of three 7-iron shaft weights on golf swing performance among golfers of varying skill levels. The study included 10 low-handicap (LH; 4.3 ± 2.4) and 10 high-handicap (HH; 29.1 ± 5.4) right-handed golfers as participants. The participants were randomly assigned 7-iron clubs with shaft weights categorized as light (77 g), medium (98 g), or heavy (114 g), and they performed test shots. Kinematic data were captured using a motion analysis system with nine infra-red high speed cameras; a force platform connected to this system was used to record weight transfer patterns. Performance variables were assessed using a FlightScope launch monitor. A two-way mixed-design analysis of variance was used to determine the significance of the performance differences among both participant groups and golf shaft weights. The results indicated that during the backswing, the LH group exhibited significantly greater maximum rightward upper torso rotation, maximum X-factor, and maximum right wrist hinge rotation than did the HH group. During the downswing, the LH group exhibited significantly greater maximum upper torso angular velocity and maximum right wrist angular velocity than did the HH group. Moreover, the LH group produced significantly higher ball speeds, longer shot distances, and lower launch angles than did the HH group. The shaft weight neither greatly altered the golf swing nor displaced the center of gravity of the golfers. The lighter shafts were observed to facilitate faster clubhead speeds and initial ball velocities, thereby resulting in longer shot distances, especially among LH golfers. Although significant differences in swing mechanics and performance exist between HH and LH golfers, lighter shafts can contribute to increased shot distances for all golfers.
14 February 2024 in Frontiers in Bioengineering and Biotechnology
The purpose of this study was to investigate the differences in attack time and lower limb biomechanics when performing fencing lunge with fencing shoes (FS) and commonly used court shoes (CS). Additionally, the study aimed to evaluate whether fencing shoes with a heel cup (FSH) could reduce lower limb impact. Thirteen female collegiate fencers who had participated in national-level competitions were recruited for this study. Participants performed the lunge on a human-shaped target while wearing FS, FSH, or CS in a randomized order. Biomechanical data were collected using a 3D motion analysis system synchronized with a force plate. A signal light, and an accelerometer were attached to the target’s head to initiate lunge movement and detect hit moment for calculating attack time. Attack time was significantly shorter when wearing FS (0.92 ± 0.05 s) and FSH (0.93 ± 0.07 s) compared to CS (0.96 ± 0.06 s). The maximum angular velocity of ankle plantarflexion in rear foot push-off phase was significantly slower when wearing FS and FSH than when wearing CS. The maximum knee posterior shear force, maximum knee flexion moment, and maximum ankle medial shear force during the front foot step phase were significantly greater when wearing FS than when wearing CS. These forces were significantly reduced or nearly significantly reduced when wearing FSH, and there were no significant differences compared to wearing CS. The maximum ankle medial shear force during the push-off phase in rear foot was the greatest when wearing FS but decreased significantly when using FSH. However, this force was still greater than when wearing CS. Wearing FS resulted in a higher loading rate (LR) on the front foot. This LR was reduced when a heel cup was used but still remained higher than when wearing CS. There were no significant differences in the forward extension of body, maximum ground reaction force, or center of pressure displacement during front foot step and rear foot push-off phases among the three shoe conditions. Wearing FS can enhance lunge performance, and the use of a heel cup can effectively reduce lower limb impact.