ABSTRACT
The aims of this study were: (i) to determine kinematic, kinetic, and electromyographic characteristics of Junzuki karate punch in professional karate athletes; (ii) to identify biomechanical parameters that correlate with punch force and lead to a higher punching performance; (iii) to verify the presence of muscle co-activation in the upper limb, trunk, and lower limb muscles. Data were collected from nine experienced karatekas from the Accademia Italiana Karate e Arti Marziali during the execution of the specific punch. Mean punch forces (181.2â N) delivered to the target, the range of motion of both right and left knees (1.13 and 0.82â rad) and right elbow (1.49â rad) joints, and the angles at impact (knee: 0.81 and 0.91â rad; elbow: 1.19â rad) in the sagittal plane were computed. Furthermore, the trunk rotational angular acceleration (63.1â radâ s-2), force related to the lower limbs (550.2 and 425.1â N), and co-activation index for the upper limb (36.1% and 34.7%), trunk (24.5% and 16%), and lower limbs (16.0% and 16.1%) muscles were evaluated bilaterally. Significant positive correlations were found between the punch force and both right and left knee flexion at the instant of impact and right and left leg force. Significant negative correlation was found between the punch force and maximum trunk angular acceleration. Significant differences (p = .03) in the co-activation index among the upper limb, trunk, and lower limbs muscles highlighted a rostro-caudal gradient on both body sides. This research could be of use to performers and coaches when considering training preparations.
Subject(s)
Athletic Performance/physiology , Martial Arts/physiology , Posture , Acceleration , Adolescent , Adult , Athletes , Biomechanical Phenomena , Elbow , Electromyography , Female , Humans , Knee , Male , Muscle, Skeletal/physiology , Range of Motion, Articular , Rotation , Torso , Young AdultABSTRACT
Forty five smokers were classified into schistosomal cases with type-2 diabetis mellitus (GI) and with associated history of bronchial asthma (GII) and without T-2 DM (GIII). A control group (GIV) of non-diabetic non schistosomal age matched subjects who quitted smoking for >6 months were included. Assessed parameters included indices of glycemic status (glycated hemoglobin), angiogenesis (vascular endothelial growth factor) hepatic and bronchoalveolar disposition (Liver function test, metallothionein, serum levels of cotinine, cadmium selenium, copper & zinc) and bronchoalveolar lavage) (BAL) levels of surfactant proteins A & D, zinc and copper oxidative stress and fibrogenesis (total antioxidant capacity thiobarbituric acid reactive substance) and vasculopathy (angiotensin converting enzyme, P-selectin, nitrate) and periodontitis (collagenase and elastase in GCF) impact of cigarette smoking associated with trace element disbalance and enzymatic changes in crevicular fluid on altered parameters collaborative out-come. The study reflected the collaborative outcome of immune mediated mechanisms initiated by liver affection, glycemic status and history of predisposed bronchial integrity induced by oxidative stress.