Showing 6 results for Biomechanics
, , ,
Volume 12, Issue 7 (4-2014)
Abstract
The main purpose of the present study was to investigate the kinematics and kinetics of successful versus
unsuccessful basketball free throw shots. Six professional basketball players (age= 23±2.09 years members
of Iranian premier basketball league participat in test. Kinematics of arm motion during basketball free throws
were recorded by two Casio zr200 camera in frequency of 240 Hz. Wilcoxon test was used for significant
differences between successful versus unsuccessful free throws (p ≤ 0/05). Angular velocity of the wrist was
found to be significantly higher in successful versus unsuccessful shots at the time of ball release (p ≤ 0/028).
Wrist (p ≤ 0/008) and shoulder (p ≤ 0/023) joints were found to have significantly more flexion in successful
versus unsuccessful shots while elbow (p ≤ 0/002) remained significantly less flexed in successful shots.
Angular displacement of wrist (p ≤ 0/034) and elbow (p ≤ 0/004) was shown to be significantly greater in
successful versus unsuccessful shots. Integrated EMG of Anterior Deltoid (AD), Triceps Brachii (TB) and
Flexor Carpi Radialis (FCR) muscles was more in successful free throw versus unsuccessful free throw, but
the only significant difference was observed in the Integrated EMG of the Triceps Brachii muscle (p ≤ 0/034).
In summery, increasing the wrist angular velocity and activity of triceps brachii muscle affected successful
free throws.
Mr Mostafa Haj Lotfalian, Dr Mahdi Kargarfard, Dr Heydar Sadeghi, Mr Sajjad Mohammadi,
Volume 14, Issue 12 (10-2016)
Abstract
Support foot position is one of the important factors which can affect instep kick quality and ankle joint injury. The aims of this study were to examine the support foot parameters in maximal instep kicking with the preferred and the non-preferred leg and research on risk factors for ankle joint injury in amateur futsal players. In this semi experimental study, twelve young and novice futsal players performed maximal speed place kicks with the preferred and the non-preferred leg. Average of the subjects individual characteristic have contained, age : 21/2±1/5 years, weight : 67/6±5/5 Kg and height :176±4/2 cm. Athletes were kicking the ball towards the goal from 10 meters. amount of support foot pressure were calculated at 300 Hz. To calculate injury of ankle joint, Forces, impulses, position of the fixed leg and maximum pressure of the lateral and medial portions of the foots were determined. Results indicated a significant difference in amount of subtalar joint range of motion. Higher range of motion in dominant leg were caused by a greater flexibility and coordination in this side of the body. In addition there were no significant different in impact of anterior, middle and posterior portion of fixed legs between two support foot. In contrast the maximum pressure in lateral side of non-preferred leg, was significantly more than other foot. In addition, the maximum force in non-preferred leg occurred prior then other foot. These problems can exacerbate ankle injury risk. Because the subjects were novice and they do not have appropriate neuromuscular coordination, can’t show a good movement pattern in non preferred leg. Hence, the absence of neuromuscular coordination can lead to energy loss and high pressure coming into the body, especially the feet and it can exacerbate injuries. In a nutshell, amateur subjects indicated higher quality of biomechanical parameters in support foot of the preferred leg. Also likelihood of ankle sprain in dominant foot was less than other. Also generalization of these results to semi-professional and professional players, need further research.
, , Elham Shirzad,
Volume 19, Issue 21 (9-2021)
Abstract
Despite the importance of talent for sports, but it has yet received little attention. The purpose of this study was to present a pattern design for talent identification in karate based on artificial intelligence algorithms. Subjects divided to adolescent elite karate athletes (n = 19) and non-karate athletes adolescent (n=20) by convenience sampling. Besed on previous literature, we selected and measured biomechanical and anthropometric variables. The normal distribution of all data was analyzed using Shapiro-Wilk test. Principal component Analysis (PCA) was performed to reduce the number of variables and identify the most important anthropometric and biomechanical variables. Then, for modeling, the neural network algorithm was used with three input layer (10 neurons), middle (7 neurons) and output (2 neurons). The results showed the most important anthropometric variables of adolescent elite karate athletes were thoracic subcutaneous fat, height, jump, static balance, grip strength, chest circumference, ankle circumference, abdominal subcutaneous fat and apparent length leg respectively. Also, percentage of correct classification and sensitive of data was high and 87% and 85% respectively. According to the results of this study, this method can be used for talent karate athletes along with other methods.
Amir Fatollahi, Amirali Jafarnezhadgero, Hamidreza Maghami,
Volume 22, Issue 27 (8-2024)
Abstract
Biomechanics is the knowledge that shows what forces enter the motion system of the human body and how it causes human movement. Therefore, the aim of this Meta-Analysis study was to review the studies conducted in the field of the effects of training on sand surface on biomechanics and physical fitness factors of human body during translational motions. The current study was a library and systematic review, the search for articles in Persian and Latin was from the beginning of the year 2000 to the end of 2023, which was done in the specialized databases of PubMed, WOS, Scopus, ISC and Google Scholar search engine. 568 related articles were selected based on inclusion and exclusion criteria. Standardized mean differences (SMDs) were calculated using random-effects models. The findings of eight articles indicated the improvement of mucle activity during training on sand. Examining the findings of one article indicated positive effects of kinematic variabls during training on sand. A number of two articles also reported that the reduction of the ground reaction forces and impact shock. In addition, five articles reported the improvement of sports performance in athletes, the increase of physical fitness factors. In general, training on sand surface can have significant positive effects on people's daily and sport life. Further study is warranted.
Hamidreza Zanguie, Mohammad Yousefi, Abbas Farjadpezeshk, Khorshid Bijari,
Volume 23, Issue 29 (7-2025)
Abstract
Aim: Most studies have compared the single-leg landing task in terms of biomechanical characteristics, especially kinematics and kinetics of movement planes, and concluded that reliability for knee valgus angles and hip adduction is moderate to excellent. However, no studies have been conducted on the reliability of different types of single-leg landing. Therefore, the purpose of this study is to review studies investigated the reliability of single-leg landing types to evaluate the biomechanics of the knee joint.
Methods: The relevant articles from valid databases with the keywords Single Leg Landing, Landing, Kinematic, Biomechanics, Return to Sport, Performance Test, Functional Test, Hop Test, Kinetic thematic search methods from 1995 to 2023 were examined.
Result: A total of 1022 articles were identified then duplicate studies were eliminated in the next stage, the titles and abstracts of the studies were reviewed and 439 studies were excluded due to inconsistency with the research question. Finally, only 9 articles that met the inclusion criteria were examined.
Conclusion: This study showed that different single-leg landing tasks for kinematic variables, including internal rotation, adduction, hip flexion, knee extension, knee valgus, trunk lateral flexion, and pelvic tilt have good reliability.
Mohadeseh Ashrafizadeh, Ali Asghar Norasteh,
Volume 23, Issue 30 (1-2026)
Abstract
Introduction & Aim: Motor control deficits such as dynamic knee valgus and quadriceps dominance are recognized as key modifiable risk factors for lower-limb injuries. Feedback-based training has been proposed as an effective strategy to correct high-risk biomechanics. This systematic review aimed to investigate the effects of feedback interventions on lower-limb mechanics and performance during jump-landing movements
Methods: A comprehensive search was conducted in international databases (PubMed, Scopus, Science Direct, Google Scholar) and national databases (Magiran, Irandoc) from 2000 to 2023. Studies were included if they examined the effects of any form of feedback on healthy individuals with lower-limb motor control deficits. From an initial 540 retrieved articles, 20 studies met the inclusion criteria after screening and full-text review.
Results: Most studies reported that feedback, particularly external or real-time feedback, led to increased flexion angles of the hip and knee in the sagittal plane during jump-landing. The findings regarding frontal plane mechanics were inconsistent: some studies showed a reduction in knee valgus angle, while others reported no significant change. A majority confirmed a reduction in peak vertical ground reaction force following feedback. However, limited studies assessed performance outcomes such as jump height or reactive strength index, and their findings were contradictory.
Conclusion: Feedback interventions appear effective in improving biomechanical risk factors related to lower-limb injury during jump-landing tasks; however, their impact on functional performance remains unclear. Further research is required to determine long-term retention and performance outcomes.
