The purpose of this study was to calculate electromyographic (EMG) power spectra of the sternocle... more The purpose of this study was to calculate electromyographic (EMG) power spectra of the sternocleidomastoid (SCM), the splenius capitis (SPL) and the trapezius (TRP) muscles from both sides of the body in bilateral lateral flexion and compare them with the EMG spectral characteristics of the same muscles in the sagittal and oblique planes recorded from the same subjects in the same experimental session but reported elsewhere in the literature. Forty normal and healthy young adults (21 males, 19 females) volunteered for the study. The subjects were prepared and positioned appropriately to exert linearly ramping isometric exertion aided by visual feedback against a rigid and load cell instrumental device. Exertions were carried out in a random order. The maximal voluntary contraction was reached within a 5-s test period. The torque and EMG from the SCM, SPL and TRP muscles were sampled bilaterally at a rate of 1 kHz. The EMG data were subjected to fast Fourier transform analysis. During lateral flexion, the torque generated by females was significantly lower than males ( P<0.01) and represented at 75% of male torque. Contrary to flexion/extension and oblique plane activities, the ipsilateral SCM was most active with highest power and up to four dominant frequencies demonstrating four distinct peaks. The bandwidth of this muscle progressively increased with the grade of contraction up to 400 Hz, similar to flexion/extension with median frequency (MF) spread between 21 and 109 Hz for males and 78 and 99 Hz for females. The ipsilateral SPL was the second most active muscle, which maintained a narrow bandwidth (200 Hz) and one dominant frequency, rising in power with increasing grade of contraction. Flexion and extension caused symmetrical activity bilaterally. The results of MANOVA revealed a significant main effect of gender, activity direction, grade of contraction and individual muscles ( P<0.001). There was a significant interaction between muscle and activity direction ( P<0.001) implying significantly different MF and mean power frequency if the direction of exertion was changed. Male and female subjects responded to direction differently ( P<0.001).
ObjectiveTo determine the prevalence of musculoskeletal disorders (MSDs) among farmers and to est... more ObjectiveTo determine the prevalence of musculoskeletal disorders (MSDs) among farmers and to establish the most common regional MSDs reported.MethodsComprehensive electronic searches of Pubmed, Web of Science, CINAHL, SCOPUS, EMBASE, Agris Database, and Cochrane Library were carried out using keywords for MSDs and farmers. Pooled estimates of prevalence with 95% confidence intervals were calculated for overall MSD prevalence and the most common regional MSDs reported.ResultsTwenty‐four studies fulfilled the inclusion criteria and were incorporated into this review. From these studies, life‐time prevalence of any form of MSD among farmers was 90.6% while 1‐year MSD prevalence was 76.9% (95% CI 69.8–82.7). The majority of studies focused on spinal MSDs with low back pain (LBP) the most frequently investigated. Life‐time LBP prevalence was 75% (95% CI 67–81.5) while 1‐year LBP prevalence was 47.8% (95% CI 40.2–55.5). The next most common regional MSDs reported were upper (range 3.6–71...
The purpose of this study was to calculate electromyographic (EMG) power spectra of the sternocle... more The purpose of this study was to calculate electromyographic (EMG) power spectra of the sternocleidomastoid (SCM), the splenius capitis (SPL) and the trapezius (TRP) muscles from both sides of the body in bilateral lateral flexion and compare them with the EMG spectral characteristics of the same muscles in the sagittal and oblique planes recorded from the same subjects in the same experimental session but reported elsewhere in the literature. Forty normal and healthy young adults (21 males, 19 females) volunteered for the study. The subjects were prepared and positioned appropriately to exert linearly ramping isometric exertion aided by visual feedback against a rigid and load cell instrumental device. Exertions were carried out in a random order. The maximal voluntary contraction was reached within a 5-s test period. The torque and EMG from the SCM, SPL and TRP muscles were sampled bilaterally at a rate of 1 kHz. The EMG data were subjected to fast Fourier transform analysis. During lateral flexion, the torque generated by females was significantly lower than males ( P<0.01) and represented at 75% of male torque. Contrary to flexion/extension and oblique plane activities, the ipsilateral SCM was most active with highest power and up to four dominant frequencies demonstrating four distinct peaks. The bandwidth of this muscle progressively increased with the grade of contraction up to 400 Hz, similar to flexion/extension with median frequency (MF) spread between 21 and 109 Hz for males and 78 and 99 Hz for females. The ipsilateral SPL was the second most active muscle, which maintained a narrow bandwidth (200 Hz) and one dominant frequency, rising in power with increasing grade of contraction. Flexion and extension caused symmetrical activity bilaterally. The results of MANOVA revealed a significant main effect of gender, activity direction, grade of contraction and individual muscles ( P<0.001). There was a significant interaction between muscle and activity direction ( P<0.001) implying significantly different MF and mean power frequency if the direction of exertion was changed. Male and female subjects responded to direction differently ( P<0.001).
ObjectiveTo determine the prevalence of musculoskeletal disorders (MSDs) among farmers and to est... more ObjectiveTo determine the prevalence of musculoskeletal disorders (MSDs) among farmers and to establish the most common regional MSDs reported.MethodsComprehensive electronic searches of Pubmed, Web of Science, CINAHL, SCOPUS, EMBASE, Agris Database, and Cochrane Library were carried out using keywords for MSDs and farmers. Pooled estimates of prevalence with 95% confidence intervals were calculated for overall MSD prevalence and the most common regional MSDs reported.ResultsTwenty‐four studies fulfilled the inclusion criteria and were incorporated into this review. From these studies, life‐time prevalence of any form of MSD among farmers was 90.6% while 1‐year MSD prevalence was 76.9% (95% CI 69.8–82.7). The majority of studies focused on spinal MSDs with low back pain (LBP) the most frequently investigated. Life‐time LBP prevalence was 75% (95% CI 67–81.5) while 1‐year LBP prevalence was 47.8% (95% CI 40.2–55.5). The next most common regional MSDs reported were upper (range 3.6–71...
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Papers by Shrawan Kumar