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

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.

Relationships between Cornell Musculoskeletal Discomfort Questionnaire and Online Rapid Office Strain Assessment Questionnaire.

BACKGROUND: The Rapid Office Strain Assessment (ROSA) is a tool employed online to screen office workstations, which may require modification to decrease musculoskeletal discomfort of workers. This study aimed to examine if the ROSA is able to evaluate pain severity in the lower back, shoulder and neck of office workers accurately. METHODS: Overall, 142 participants (height: 1.80 ± 0.15 m, BMI: 26.08± 6.70, age: 35±15 yr) with at least a year of working experience completed both questionnaires, the online ROSA and the Cornell musculoskeletal discomfort, in 2016 in Malaysia. RESULTS: Relationship between the total scores of both questionnaires for lower back, shoulder and neck pain were significant but exhibited a weak to moderate relationship (range of r values from 0.012 (CI 95%, -0.153-0.176) to 0.503 (CI 95%, 0.369-0.616). CONCLUSION: The online ROSA does not appear to be a reasonable tool for evaluating the severity of lower back, shoulder and neck pain among office workers as the correlations were low. We suggest continued use of the musculoskeletal discomfort questionnaire. Additional studies are required to further examine the ROSA for other anatomical regions.

Exploring cancer development in adulthood: cholinesterase depression and genotoxic effect from chronic exposure to organophosphate pesticides among rural farm children.

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 children's 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.