Force and velocity of impact during upper limb strikes in combat sports: a systematic review and meta-analysis.

Upper limb strikes are frequent movements in combat sports and self-defence systems, in which numerous types of strikes can be applied. Therefore, the aim of this systematic review and meta-analysis was to summarise and compare the mechanical consequences of different types of upper limb strikes among various sports disciplines. A literature search was conducted in Scopus and Web of Science, with the following search formula: (impact force) AND (strike) AND (taekwondo) OR (karate) OR (self-defence) OR (combat sport) OR (boxing). The search resulted in 28 studies describing 9 kinds of strikes, where straight punches and reverse punches have larger mean impact forces than the kung fu punch (p < 0.001) and that a palm strike had a lower strike velocity (p < 0.001) than a reverse punch, straight punch, or junzuki punch. The highest recorded mean force was found for a straight punch (3427 N). Athletes in mixed martial arts, trainers of self-defence or tactical coaches can expect that straight punches and reverse punches should be performed at high speeds (over 10 m/s) and provide similar or larger impacts than other upper limb strikes; therefore, those punches should favour a combat athlete to win a competition or succeed in self-defence.

Analysis of the Contact Area for Three Types of Upper Limb Strikes.

Performance in strike combat sports is mostly evaluated through the values of the net force, acceleration, or speed to improve efficient training procedures and/or to assess the injury. There are limited data on the upper limb striking area, which can be a useful variable for contact pressure assessment. Therefore, the aim of this study was to determine the contact area of the upper limb in three different strike technique positions. A total of 38 men and 38 women (n = 76, 27.3 ± 8.5 years of age, 73.9 ± 13.8 kg of body weight, 173.3 ± 8.4 cm of body height) performed a static simulation of punch with a fist, palm strike, and elbow strike, where three segments of the right upper limb were scanned. The analysis of 684 images showed a correlation (r = 0.634) between weight and punch technique position in men and significant differences in elbow strike (p < 0.001) and palm strike (p < 0.0001) between women and men. In both groups, the palm demonstrated the largest area and the elbow the smallest one. These data may be used to evaluate strike contact pressure in future studies in forensic biomechanics and assessment of injury in combat sports and self-defense.

Upper Limb Strikes Reactive Forces in Mix Martial Art Athletes during Ground and Pound Tactics.

Athletes of mixed martial arts use a ground and pound strategy with the strikes in the dominant ground position. The aim of this study was to compare the average peak force (Fpeak) among three punches and to estimate the probability of achieving a skull bone fracture force of 5.1 kN for each type of strike in male and female athletes. A total of 60 males and 31 females (26 ± 8 years, 75 ± 20 kg, 177 ± 11 cm) practicing professional self-defense at the advanced and professional levels performed 15 strikes on a force plate. The analyses of 1360 trials showed significant differences among the strikes Fpeak in females (p < 0.01) and males (p < 0.01). Straight punches had lower Fpeak than palm strikes and elbow strikes in both genders, and palm strikes had higher Fpeak than elbow strikes in females. No difference was observed between palm strikes and elbow strikes in males (p = 0.09). The ground and pound strikes resulted in higher impacts than previously reported strikes in the standing position. Male athletes can deliver a Fpeak above 5.1 kN with a probability of 36% with elbow and palm strikes. Such forces can cause head injury; therefore, the use of these strikes in competition should be carefully considered.