Biomechanics research of soccer skills has greatly lagged behind the sport’s popularity compared to many other sports. Even for basic skills, such as the maximal instep kick, relatively few quantitative studies exist. Further, most of these fail to provide practical means to judge kick quality. The current study proposes to address this deficiency by establishing user-friendly regression equati...

Evidence from pulsar wind nebula symmetry axes and radio polarization observations suggests that pulsar motions correlate with the spin directions. We assemble this evidence for young isolated pulsars and show how it can be used to quantitatively constrain birth kick scenarios. We illustrate by computing several plausible, but idealized, models where the momentum thrust is proportional to the n...

We have recently measured the angle between the spin and orbital angular momenta of PSR B1534+12 to be either 25 ± 4 or 155 ± 4. This misalignment was almost certainly caused by an asymmetry in the supernova explosion that formed its companion neutron star. Here we combine the misalignment measurement with measurements of the pulsar and companion masses, the orbital elements, proper motion, and...

The aim of the paper is to present the analysis of the influence of chosen kinetic factors on the side-kick technique. This issue is of a significant importance in the traditional version of Taekwon-do, where a single strike may reveal the winner. A male athlete, a black-belt holder, has participated in this case study. Generally accepted criteria of sports technique biomechanical analysis were...

The aim of this study was to investigate somatic properties and force production of leg extensor muscles measured in the countermovement jump test (CMJ), as well as to analyse kinematic variables of sprint surface butterfly swimming. Thirty-four male competitive swimmers were recruited with an average age of 19.3 ± 1.83 years. Their average body height (BH) was 183.7 ± 5.93 cm, body fat content...

The aim of this study was to examine the effect of a soccer (strength and technique) training program on kinematics and electromyographic (EMG) muscle activity during a instep kick. Ten amateur soccer players (aged 19.9+/-0.4 years, body mass 74.8+/-9.1 kg, height 177.4+/-6.7 cm) constituted the experimental group (EG) whereas 10 players (age 21.6+/-1.3 years, weight 71.5+/-6.7 kg, height 175.2...