Matiur Rahman

Non-invasive electromyography-based fatigue detection and performance analysis on m. biceps brachii muscle

Muscle fatigue occurs most frequently due to repetitive movements in our day-to-day activities. The powerful use of muscles might cause a decline in performance. In this study, the effects of muscle fatigue involving only the m. biceps brachii muscle in the dominant upper arm were investigated during the course of an arm wrestling game where the muscle contractions were produced by the winner and loser, respectively. This competition was conducted to monitor the progress/ decline of muscle strength among young players. Eight male subjects (age: 26±3 years, height: 170±13 cm, weight: 70±13 kg and BMI: 21±4) were participated in this study. Electrodes were placed on the middle of the biceps muscle to record the electromyography (EMG) signals. Each group (two players) participated twice with each other, and the EMG signals were recorded. Muscle fatigue was analyzed and compared using the first-time and second-time EMG data. The results were evaluated by calculating the average EMG, root mean square (RMS) and the highest peak of the signal during muscle contraction. Among these, RMS and highest peak values helped in efficiently assessing muscle fatigue. Most of the results indicated that m. biceps muscle reduced its strength during the second game; also, winners performance were found to be better than the losers (according to EMG amplitudes). The current findings regarding the m. biceps brachii muscle might prove to be useful in developing effective injury prevention and rehabilitation strategies, and other physiological measurements related to the upper arm muscles.

SIGNIFICANCE OF THE ELECTROMYOGRAPHIC ANALYSIS OF THE UPPER LIMB MUSCLES OF CRICKET BOWLERS: RECOMMENDATIONS FROM STUDIES OF OVERHEAD-THROWING ATHLETES

The purpose of this study was twofold: (i) to review the existing literature on electromyographic (EMG) analysis of the upper limb muscles of present overhead-throwing (OT) athletes during throwing and of cricket bowlers (CBs) during cricket bowling (CB) and, (ii) to discuss the importance of and generate recommendations for the EMG assessment of the muscle activity of CBs with respect to previous studies of OT athletes. A literature search of the PubMed, Scopus and Google Scholar electronic databases was performed to identify relevant articles published up to December 2012. This search was performed to evaluate the following areas, (i) what are the upper limb muscles that should be evaluated during OT sports and cricket bowling? (ii) what types of EMG methodologies have been used? (iii) what are the anthropometric, performance and physical functional variables that are usually selected? and (iv) what recommendations can be made for the assessment of the muscle activity of CBs? The search identifies 32 publications on OT athletes and 4 on CBs. The results note the following conclusions: (i) there are relatively few CB-related papers that utilize EMG, particularly for the assessment of muscle activity and coordination, (ii) a total of 22 upper limb muscles were investigated using EMG (from both criteria), (iii) surface electrodes are used more frequently than needle electrodes, (iv) most of the article normalized and analyzed the EMG amplitudes than the frequency, and the data was more often analyzed through a descriptive statistical analysis and (v) the majority of the studies analyzed the right limb of physically normal (uninjured) males both the amateur and professional athletes that were 20 to 29 years of age. Finally, the published evidence on CBs is inadequate to validate a sound recommendation for the assessment of the muscles of CBs using EMG. However, the studies on OT athletes do provide guidelines that can be used to analyze CBs. The overall conclusion of this review show that, further studies are needed to evaluate the efficacy of EMG for the assessment of the upper limb muscle of CBs to ultimately identify and prevent injury which is still a matter of discussion in the sports medicine community.

Effects of anthropometric variables and electrode placement on the SEMG activity of the biceps brachii muscle during submaximal isometric contraction in arm wrestling.

Abstract Surface electromyography (SEMG) has been widely used to analyze the biceps brachii (BB) muscle during voluntary contraction, and the effect of the interelectrode distance has been studied. However, the effect of anthropometric variations and the placement of electrodes on the BB activity during arm wrestling (i.e., during isometric contraction at a submaximal intensity) has seldom been investigated. In this study, the BB strength throughout this type of static contraction was evaluated. The SEMG signals were recorded from three locations on the BB: the muscle belly (M), near proximal (P), and distal tendon (L) regions. Twenty subjects who participated in the experiment were divided into five groups (A, B, C, D, and E). The average SEMG, root mean square, and variability of the signal were calculated using the coefficient of variance. The results indicated that the M region was more active and exhibited increased signal consistency (10.91%) compared with the other two regions (P: 24.47% and L: 19.13%). Significant differences were observed between the L and P regions and between the M and P regions (p<0.05); however, there were no differences between the M and L regions (p>0.05). The increase in the SEMG value in groups B and C was significant (p<0.05), whereas groups A, D, and E did not exhibit a significant increase (p>0.05). In addition, muscle size was the strongest predictor of strength compared with body weight and height. The results suggest that the M region displays considerable SEMG effects and signal reliability. Furthermore, the SEMG measurements were found to correlate strongly with the strength of the contractions and the muscle size, and not with weight and height.

Age Related Differences in the Surface EMG Signals on Adolescent's Muscle during Contraction

The aim of this study was to investigate whether there are differences in the amplitude of the EMG signal among five different age groups of adolescents muscle. Fifteen healthy adolescents participated in this study and they were divided into five age groups (13, 14, 15, 16 and 17 years). Subjects were performed dynamic contraction during lifting a standard weight (3-kg dumbbell) and EMG signals were recorded from their Biceps Brachii (BB) muscle. Two common EMG analysis techniques namely root mean square (RMS) and mean absolute values (MAV) were used to find the differences. The statistical analysis was included: linear regression to examine the relationships between EMG amplitude and age, repeated measures ANOVA to assess differences among the variables, and finally Coefficient of Variation (CoV) for signal steadiness among the groups of subjects during contraction. The result from RMS and MAV analysis shows that the 17-years age groups exhibited higher activity (0.28 and 0.19 mV respectively) compare to other groups (13-Years: 0.26 and 0.17 mV, 14-years: 0.25 and 0.23 mV, 15-Years: 0.23 and 0.16 mV, 16-years: 0.23 and 0.16 mV respectively). Also, this study shows modest correlation between age and signal activities among all age groups muscle. The experiential results can play a pivotal role for developing EMG prosthetic hand controller, neuromuscular system, EMG based rehabilitation aid and movement biomechanics, which may help to separate age groups among the adolescents.

Performance Analysis of WDM-PON System Based on Optimized Remotely Pumped Erbium-Doped Fiber Amplifier (EDFA) Parameter

Abstract In this paper, the performance of wavelength division multiplexing-passive optical network (WDM-PON) system using the erbium-doped fiber amplifier (EDFA) is optimized and evaluated. The optimization is analyzed by finding the EDFA length range at which the output power produced are the highest and the pump power range at which the gain flatness produced are within the effective range (0.3 dB). After the optimization process, the optimized EDFA system produces the gain of 26.6±0.292 dB, noise figure of 3.82 dB and output power of 7 dBm and the system is then implemented into WDM system. The performance of WDM system is compared against the system without EDFA in terms of bit error rate (BER). Results obtained prove that the proposed system with the EDFA consistently performs better than the conventional system.

Large negative dispersion with residual dispersion (Dr) compensation over E+S+C+L+U wavelength bands by using single mode hexagonal Photonic crystal fiber (H-PCF)

In transmission media the Photonic crystal fibers (PCFs) are highly suitable for wavelength-division-multiplexing (WDM) systems. This paper exhibit a Hexagonal Photonic Crystal Fiber (H-PCF) that mention simultaneously high birefringence, large nonlinearity and high negative dispersion. The proposed H-PCFs shows a large negative dispersion coefficient of about -188 to -435 ps/(nm.km) over E and U-bands along with relative dispersion slope (RDS) perfectly matched to that of single mode fiber of about 0.0036 nm-1. Besides according to simulation, the birefringence of the desired designed is 1.27×10-2 with the large nonlinear coefficient is 51.54W-1Km-1 at the operating wavelength of 1550 nm.

Performance Analysis of Hybrid OCDMA/WDM System for Metro Area Network

Abstract In this study a hybrid spectral amplitude coding for optical code division multiple access (i.e., called OCDMA) over wavelength division multiplexing (WDM) network is proposed to support large number of subscribers. The proposed system combines two different techniques, namely OCDMA and WDM. The modified double weight (MDW) code is used as a signature address for designing the system. This code has numerous advantages such as this code can accommodate more number of simultaneous active users under considerable standard bit error rate (e.g. ≤10−9) and shorter code length. The proposed system can enhance the network capability to support high number of users. Therefore, this system can be considered as a promising solution for Metro Area Network (MAN).