فهرست مطالب

  • Volume:2 Issue: 2, 2018
  • تاریخ انتشار: 1397/04/10
  • تعداد عناوین: 7
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  • Abbas Meamarbashi * Pages 1-5

    Physical activity monitoring is important to record all the daily physical activities for the purpose of fitness and health. This motive caused a tremendous progress in the wearable technologies. Current project encompasses 9 degree of freedom inertial sensor (triaxial accelerometer, gyroscope, and magnetometer) with Wi-Fi communication in a very small wearable data logger integrated with a web server. It is applicable as on-body sensor network for more intricate activity recognition applications. Inertial sensor data measured and transferred to either a custom designed web server in online mode or stored in a MicroSD memory card in the offline mode. Wearable data logger with 18×30×30 mm (W×L×H) and 20 grams weight designed and produced. The system was tested at 200 Hz during online mode and acceptable precision and noise ascertained. Current device provided movement recording with wireless communication in small size and low cost to be applicable in the health and fitness applications.

    Keywords: Data Logger, Inertial sensor, Wi-Fi, Fitness
  • Abbas Meamarbashi Page 2
  • Behrouz Hajilou *, Mehrdad Anbarian, MohammadHossein Ghasemi, Ali Jalalvand, Bahman Miripour Pages 6-14

    Tibialis posterior muscle dysfunction leading to adult acquired flatfoot deformity. Tibialis posterior muscle dysfunction is commonly treated with a flexor digitorum longus tendon transfer to the tubercle of navicular bone. In recent years, the dynamic computer modeling has been used to predict the results of surgical and treatment. The aim of this study was to provide a dynamic computer model of flexor digitorum longus tendon transfer for predicting the outcome of flat foot treatment. In this study the 3D model of ankle joint, which consists of 29 bones and 12 muscles was developed in OpenSim. Using software, ankle plantar flexion moment, metatarsophalangeal joints moment and inversion moment of subtalar joint were drawn. After flexor digitorum longus tendon transfer, there were decreases ankle plantar flexion moment (6.7%), metatarsophalangeal joints moment (45%) and inversion moment of subtalar joint (34%). Plantar flexion moment reduction caused no significant changes in the ankle joint, but reduction in metatarsophalangeal joints could limit heel lift during propulsive phase in walking or running. A decreased inversion moment at the subtalar joint could alter the biomechanics of lower extremities

    Keywords: Flexor digitorum longus tendon, Flatfoot, Modeling, OpenSim
  • Masoud Darabi *, Nasrin Azizian, Mehrdad Moharramzadeh, Farzad Nobakht Pages 15-27

    The purpose of this study was to process and analysis of the electroencephalography signal to assess the effect of sport advertisement on the customers. Forty university student athletes, which were interested and uninterested to the Nike brand were selected (all right handed with 18-25 years old). They were 10 male interested athletic, 10 male uninterested athletes, 10 female interested athletes and 10 female uninterested athletes. When brain waves were registered by the electroencephalography device, Brian mapping software and math analysis used to change information to numeric data. Data analyzing by variant analysis test with Repeated Measures ANOVA and LSD test was done. The results showed that the activity of alpha, beta and theta waves in the interested group had a significant increase. Moreover, the activity of alpha and theta in uninterested group was not significantly different. Results showed that it's possible to find out the effect of sport advertisement Nike brand on brain waves (alpha, beta, delta and theta) by registering the customer's brain waves by electroencephalography. Moreover, by processing and analyzing the signals, we conclude that advertisements increase the amount of analytic and focused thinking, as well as arousal, and can play a significant role into decision making.

    Keywords: Electroencephalography, Brain waves, Advertisement, Nike brands, Athletes
  • Marefat Siahkouhian *, Elahe Mamashli, Zohre Behbudi, Aylar Imani Pages 28-34
    Aim

    The aim of this study was to determine the aerobic threshold by means of the maximum distance method (Dmax) based on heart rate performance curve (HRPC) in active young men.

    Methodology

    For this purpose, in a laboratory trial, 35 active young men (Age 22.03 ± 2.20 years, Height 176.26 ± 6.65 cm, Weight 68.94 ± 9.56 kg and body fat 17.8 ± 3.41%) were selected on a targeted basis as subjects and executed the Conconi standard protocol. The aerobic threshold of the subjects was determined by means of criterion method (respiratory gas analysis) and maximum distance model based on HRPC. Bland–Altman plots, Intraclass Correlation Coefficient and Paired Sample T-test were used for data analysis.  

    Results

    The aerobic threshold of all of the subjects was obtained by the means of the HRPC using the method of Dmax. However, supplementary results revealed that moderate agreement exist between two methods (±1.96; CI = 95%, -35.9 to +32.8 b/min). Similarly, significant but moderate Intraclass Correlations observed (ICC= 0.312), while there was no significant differences exists between two methods (p= 0.599).

    Conclusion

    The application of the Dmax method based on HRPC model in predicting of the aerobic threshold gives us relatively good results. Therefore, the HRPC model can be useful method for predicting the aerobic threshold.

    Keywords: Aerobic threshold, Maximum distance method (Dmax), HRPC
  • Stefan Kolimechkov *, Lubomir Petrov, Albena Alexandrova, Kostadin Cholakov Pages 35-40

    The 20m shuttle run test (20mSRT) is applied for assessing cardiorespiratory fitness, and is included in many fitness test batteries, such as Eurofit, Alpha-fit, FitnessGram, etc. The aim of this study was to validate software, specially designed by us (BeepShuttle Junior), which administers the 20mSRT, calculates the maximal oxygen uptake (VO2max) in children and adolescents from 6 to 17 years of age, and classifies them in accordance with comprehensive gender- and age-specific international norms. This software supports the administration of the 20mSRT with an appropriate animation and audio signals. The most recent VO2max reference standards were combined in order to assess cardiorespiratory fitness. The results can be exported in an Excel compatible CSV file for additional analyses. A total of 63 children (31 girls and 32 boys) from London, aged from 6 to 9, were tested with the BeepShuttle Junior software, which calculated VO2max and percentile scores for each child. The boys performed significantly better than girls in cardiorespiratory fitness (47.7 ± 3.1 vs 45.9 ± 2.2 ml/kg/min respectively, p < 0.05), but the mean percentile scores for boys and girls were similar (53.2 ± 23.6 and 53.9 ± 22.1 respectively). This software computes the percentile score for the exact age (years, months) and the exact VO2max of each participant by linear interpolation. The individual results and assessments completely matched the interpolated normative data tables.

    Keywords: 20m shuttle run test, cardiorespiratory fitness, maximal oxygen uptake, children, adolescents, beep test
  • Ali Sharifnezhad *, Moein Koohestani, Henning Budde Pages 41-48

    A growing body of evidence indicates that different neural control strategies may exist for human contractions. This brief systematic review focuses on the specificity of the control strategy used by the central nervous system during eccentric contractions. The findings of previous studies indicate the effects of eccentric exercise on cortical regions and their cooperation as functional networks that support motor functions. Articles were searched in international databases including PubMed, Web of Science and Google Scholar. After initial screening and deleting irrelevant studies, 10 studies were chosen for the analysis. Studies were assessed and analyzed methodologically. Proper interventions were selected according to the least error criteria or the degree of strength. There is lack of study investigating the effects of muscle contraction types (isometric, concentric and eccentric) on the central nervous system, which is reflected in the EEG. Then, further investigations should answer this question: “how does the EEG-measured brain activity for the following bands (delta 1-4 Hz, theta 4-8 Hz, alpha 8-13 Hz and beta 13-20 Hz) change during acute eccentric and concentric contractions”. Moreover, this review highlighted that (1) Few neuroimaging studies have explored the brain activation during eccentric actions, (2) Brain activity in motor-related cortices is higher during eccentric than concentric actions and (3) Prefrontal cortex appears to be highly involved in the regulation of cortical motor drive during eccentric contractions.

    Keywords: Eccentric contraction, Brain activation, Electroencephalography (EEG), Functional magnetic resonance imaging (fMRI)