Shamsul Bahri Mohd Tamrin

Intensive resistance exercise and circadian salivary testosterone concentrations among young male recreational lifters.

Abstract Shariat, A, Kargarfard, M, Danaee, M, and Bahri Mohd Tamrin, S. Intensive resistance exercise and circadian salivary testosterone concentrations among young male recreational lifters. J Strength Cond Res 29(1): 151–158, 2015—Strength and morphological adaptations to resistance exercise are mediated in part by anabolic hormones such as testosterone, yet the time course of variability in circadian hormone concentrations is not well characterized. This study, investigated how the circadian rhythm of salivary testosterone is altered by resistance exercise in young men. Twenty healthy young male recreational lifters (age, 18.0 ± 1.3 years) with 2 years of experience in weightlifting were recruited. A randomized controlled trial was conducted, and subjects were randomly assigned to either the resistance exercise group (n = 10), who completed a series of resistance exercise (3 times a week, in the afternoon, 6–7 repetitions, at 85% of 1 repetition maximum for 3 weeks), or a control group (n = 10), who did not exercise during the 3 weeks. Before and after the study, an unstimulated saliva sample (2 ml) was taken every 2 hours for a maximum of 16 hours during each day. A significant decrease was observed in the resistance exercise (44.2%, p = 0.001) and control group (46.1%, p = 0.001) for salivary testosterone at each time point compared with baseline (p = 0.001). There was also no significant difference between the exercise and resting conditions in both groups for salivary testosterone (p > 0.05), except a significantly higher increase by 38.4% vs. −0.02% (p = 0.001), at 1730 hours during exercise sessions in the resistance exercise group compared with the control group. Resistance exercise has no noteworthy effect on circadian secretion of salivary testosterone throughout the 16 waking hours. These results indicate that athletes can undertake resistance exercise in either the morning or afternoon with the knowledge that a similar testosterone response can be expected regardless of the time of day.

The Prevalence of Musculoskeletal Disorder and Association with Productivity Loss: A Preliminary Study among Labour Intensive Manual Harvesting Activities in Oil Palm Plantation

Production agriculture such as harvesting in oil palm plantation has been frequently associated with MSD and significant loss of productivities. This study tends to evaluate from the viewpoint of health, the association between self-reported prevalence of musculoskeletal disorders and productivities; the impact of musculoskeletal disorders on productivity. A cross-sectional study was conducted among 143 harvesters in oil palm plantation. A general questionnaire was used to collect socio-demographic background data while Nordic Musculoskeletal Questionnaire was used to determine the prevalence of MSD. Expressed in 4 different indicators; daily harvesting quantity, efficiency score, sick leave and presenteeism, the productivity data were analysed for association. There is significant association between reported acute prevalence of MSD (within 7 d) and productivity loss in terms of presenteeism (χ2=5.088; p<0.05) as well as quantity of daily harvest (χ2=7.406; p<0.01). Logistic regression adjusted for age, BMI and smoking indicate that harvesters with MSD (past seven days) were more likely to be engaged in presenteeism (OR=2.87 95% CI=1.34, 6.14) and had lower daily productivity (OR=2.09 95% CI=1.02, 4.29) compared to harvesters without MSD (past 7 d). This study reveals that oil palm harvesters suffering acute MSD (for the past week) were likely to be still present to work and produce half lesser than their healthy counterparts. Thus, further study with comprehensive surveillance strategy is essential in order to determine the urgency or need of appropriate intervention.

The Bahasa Melayu version of Cornell Musculoskeletal Discomfort Questionnaire (CMDQ): Reliability and validity study in Malaysia.

BACKGROUND The Cornell Musculoskeletal Discomfort Questionnaire (CMDQ) was developed to assess the level of musculoskeletal discomfort among office workers related to their ergonomic situation. OBJECTIVE The primary objective of this initial study is to analyze the validity and dependability of the Malay translation of the Cornell Musculoskeletal Discomfort Questionnaire. METHODS The questionnaire was self-administered two times, with an interval of two weeks in order to evaluate the accuracy of the original findings with a retest. The study involved 115 participants. RESULTS The range of Cronbach Alpha coefficient showed a considerable consistency of the items for each sub-scale (Cronbachs a > 0.95). The range of Kappa coefficients was between (ICC = 0.690-0.949, p < 0.001), (ICC = 0.801-0.979, p < 0.001) and (ICC = 0.778-0.944, p < 0.001) for frequency, severity and interference scales. CONCLUSIONS This research, introduced the Malay-language version of the CMDQ (CMDQ-M) as the first formal validation of the CMDQ, and confirmed a high reliability and validity for the evaluation of musculoskeletal discomfort among the study population.

Exploring Cancer Development in Adulthood: Cholinesterase Depression and Genotoxic Effect From Chronic Exposure to Organophosphate Pesticides Among Rural Farm Children

ABSTRACT Children are the vulnerable group in the agricultural community due to their early exposure to pesticides through the dynamic interplay between genetic predisposition, environment, and host-related factors. This study aims to identify the possible association between the depression in blood cholinesterase level and genotoxic effect among farm children. The results of micronuclei assay and comet assay showed that the reduced blood cholinesterase level from organophosphate pesticide exposure is significantly associated with an increase in chromosome breakage and DNA strand breaks. These genotoxicity end points suggest that farm childrens cells experience early DNA damage that may lead to uncontrolled cell proliferation during their adulthood. Thus, farm children who grow up near pesticide-treated farmland have a higher probability of developing cancer than children with minimal or zero exposure to pesticides.

Risk factors of musculoskeletal disorders among oil palm fruit harvesters during early harvesting stage.

This cross-sectional study intends to investigate the associations of musculoskeletal disorders (MSDs) among foreign labourers on a socio-economic background, occupational exposure, social lifestyle, and postures adopted during harvesting tasks. A total of 446 male respondents (263 FFB cutters; 183 FFB collectors) were studied using an interview-assisted questionnaire. OWAS was used to determine the severity of awkward posture based on videos of harvesting tasks recorded for each respondent. Analysis found that increasingly educated respondents had higher risk of developing MSDs. Shorter daily work duration and longer resting duration appear to increase the risk of neck and shoulder disorders among harvesters, which may be attributable to organizational work design. Awkward posture was a particularly significant risk factor of MSDs among FFB collectors. Among the results of the study, occupational exposure, postures and certain socio-demographic backgrounds explained some, but not all, the risk factor of MSDs among harvesters. An in-depth investigation, preferably a longitudinal study investigating the dynamic of work activities and other risk factors, such as psychosocial risk factors, are recommended.

Efficacy of massage on muscle soreness, perceived recovery, physiological restoration and physical performance in male bodybuilders.

Abstract It is believed that sport massage after intensive exercise might improve power and perceptual recovery in athletes. However, few studies have been done in this area. This study aimed to examine the effect of massage on the performance of bodybuilders. Thirty experienced male bodybuilders were randomly assigned to either a massage group (n = 15) or a control group (n = 15). Both groups performed five repetition sets at 75–77% of 1RM of knee extensor and flexor muscle groups. The massage group then received a 30-min massage after the exercise protocol while the control group maintained their normal passive recovery. Criteria under investigation included: plasma creatine kinase (CK) level, agility test, vertical jump test, isometric torque test, and perception of soreness. All variables were measured over 6 time periods: baseline, immediately after the DOMS inducing protocol, right after the massage, and 24, 48, and 72 h after the massage. Both groups showed significant (P < .001) decreases in jumping, agility performance, and isometric torque, but significant (P < .001) increases in CK and muscle soreness levels. The massage group in general demonstrated a better recovery rate. As such, a post-exercise massage session can improve the exercise performance and recovery rate in male bodybuilders after intensive exercise.

Strength-training and biological rhythm of male sex hormone among judoists

Testosterone is a steroid hormone that is secreted by the testes with a diurnal rhythm and has a strong anti-catabolic (anabolic) effect on muscles. There is a strong relationship (r > 0.9) between concentrations of testosterone in the saliva and blood. The main purpose of the current study is to investigate the effect of strength-training on levels of salivary testosterone in male judoists. In a cross-sectional investigation, a population of 18 fit young male judoists (aged 17.0 ± 1.2 year, body mass 72 ± 3 kg, height 175 ± 3 cm, means ± SD), with at least 1.5 years of experience in judo classes was examined in Isfahan, Iran, in December, 2012. The period of testing consisted of two days of “rest” and two days of “exercise”. Subjects were randomly divided into two conditions that performed either the “rest” or “exercise” days during the first week, with the opposite type of day in the second week. The training regimen consisted of three repetitions of nine tasks, with 1 min of rest between each of the three sets, performed on alternate days for 8 weeks. Unstimulated saliva was collected (1–2 ml) every 2 h from 06:00 till 22:00 h. ANOVA with repeated measures was used to assess differences between the rest and exercise days. Strength-training sessions caused a significant decrease in testosterone levels immediately after exercise (p < 0.001), but there was no significant difference between the daily profiles of testosterone during the rest or exercise days (p > 0.05). It is concluded that strength-training does not significantly affect the normal biological rhythm of salivary testosterone during the waking period in male judoists.

The application of a feasible exercise training program in the office setting

BACKGROUND Previous research support the claim that people who work in offices and sit for a long time are particularly prone to musculoskeletal disorders. OBJECTIVE The main objective of this paper is to introduce an exercise training program designed to decrease muscle stiffness and pain that can be performed in the office setting. METHODS Forty healthy office workers (age: 28±5.3 years old; body mass: 87.2±10.2 kg; height: 1.79±0.15 m) apart from suffering from any sub-clinical symptoms of muscle and joint stiffness, and who had at least two years of experience in office work were chosen and randomly assigned to either an experimental group (n = 20) or a control group (n = 20). The experimental group performed the exercise training program three times a week for 11 weeks. The Cornell Musculoskeletal Discomfort Questionnaire was used to measure the pain levels in the neck, shoulders, and lower back areas. The Borg CR-10 Scale was used to measure their perceived exertion when doing the exercises, and a goniometer was used to measure the changes in range of motion (ROM) of the neck, hips, knees, and shoulders. RESULTS The overall results indicated that the exercise program could significantly (p < 0.05) reduce the neck, shoulders, and lower back pains of the participants in the exercise group while those in the control group showed no improvement in those pains. There were significant (p < 0.05) increases in the ROM of the hips, the neck, both knees and shoulders in the exercise group. Participants showed significant (p = 0.011) decreases in perceived exertion scores after the exercises. CONCLUSIONS The exercise training program designed in this study not only can effectively reduce neck, shoulders, and lower back pains, but also can improve the ROM or flexibility of the office workers.

Characterization of Risk Factors for DNA Damage Among Paddy Farm Worker Exposed to Mixtures of Organophosphates

This is a cross-sectional study conducted among paddy farmers to characterize potential risk factors that influence levels of DNA damage from exposure to mixtures of organophosphates. Comet assay was used to determine the level of DNA damage by measuring the comet tail length from the exfoliated buccal mucosa. The result suggests that farmers who chronically exposure to a mixture of organophosphates has at least 2-fold significant increase of DNA damage as compared with control group. Factor analysis and linear regression both suggest that DNA damage reported by farmers may influence individual, occupational, and residential factors and are reported as significant predictor factors, whereas this effect is mainly caused by individual factors among the control group. The findings of the present study suggest that either farmer or control group bear certain extent of genotoxic burden contributed by different risk factors.

Vibration exposure and work‐musculoskeletal disorders among traffic police riders in Malaysia: A review

Background: The traffic police force is one of the occupations that utilize motorcycles as the main mode of transport. The main ergonomic hazard with the constant use of motorcycles is exposure of riders to vibration while riding their motorcycles, which can potentially lead to work.related musculoskeletal disorders (WMSDs). Objective: This review is meant to provide an overview of the available vibration exposure with WMSDs for traffic police riders and to review the related guidelines. Method: This study involved comprehensive search of database from 1945 to 2015. Published research paper that reported on the vibration exposure, prevalence, and/or risk factors of WMSDs and occupational riders were assessed and reviewed. Result: The review suggests that the main factors involving vibration in motorcycles come from the motorcycles itself, the posture of the hands and arms during the gripping of the handlebars, the surrounding environment, and the period of riding motorcycles. Majority of the studies agreed that police riders had higher percentage of WMSDs especially in lower back, neck, and shoulder. Conclusion: Overall, police riders have a high incidence of WMSDs, which in combination with exposure to vibrations with prolonged sitting and static posture may increase their susceptibility to WMSDs. Further research is required to explore the level of exposure to vibrations and WMSDs among traffic police riders, its potentially consequences, and ways to reduce exposure and risk associated with vibrations and WMSDs.