Frontal asymmetry: A novel biomarker for physical activity and sedentary behavior.

Past research has demonstrated that regular physical activity provides a myriad of physical, mental, and emotional benefits. The decision of whether to partake in physical activity (PA) or remain sedentary appears to be partially influenced by motivational and emotional systems. Research suggests left frontal alpha asymmetry is a neural marker of approach motivation. However, studies have not explored whether habitual levels of PA and sedentary behavior relate to this neurophysiological signal. Across two studies, individuals completed measures of habitual PA and sedentary behavior using the International Physical Activity Questionnaire-Short Form. Then, resting electroencephalography activity was recorded. Results of Study 1 (N = 32, 72% women) indicated that more time spent sitting on both weekdays and weekend days were associated with less left frontal asymmetry (r = -.45, p = .027, and r = -.55, p = .005, respectively). Study 2 recruited a larger sample (N = 96, 31% women) and investigated moderators. Greater levels of moderate (r = .27) and total (r = .29) PA were associated with greater left frontal asymmetry (ps < .05), and the relationship between sedentary behavior and less left frontal asymmetry was moderated by sex (weekday: ß = .62, p = .011; weekend day: ß = .41, p = .034). Our results suggest that left frontal asymmetry may be a novel neurophysiological marker for PA and sedentary behavior.

Correlation between Reproductive Hormonal Level and Osteoporosis among Women in Mongolia.

BACKGROUND: Postmenopausal osteoporosis is the most common bone metabolic disease associated with low bone mineral density (BMD) and osteopathic fragility fractures, which can lead to significant morbidity. The objective of this study was to investigate the relationship between serum follicle-stimulating hormone (FSH), luteinizing hormone (LH), and estradiol (E2) levels and bone mineral density (BMD) across the stages of menopause in Mongolian women. METHODS: Two hundred sixty participants aged 50.1±4.4 years were enrolled in the study. Blood samples were obtained from each participant and analyzed using ELISA. Data were first stratified and analyzed by bone mineral density status (osteoporotic, osteopenic, and normal) and then by menopause status. Between group differences were analyzed using t-tests, and correlations were assessed using the Spearman rank order test, with Bonferonni correction. The data were analyzed using Statistical Package Statistical Software version 20.0 (SPSS Inc., Chicago, IL). Significance was set at p<0.05. RESULTS: The mean menopausal age was 48.4±3.4, which is comparable to the Mongolian population mean menopausal age. The mean serum estradiol level in the normal BMD group was 18.3±13.1 pg/ml and 15.8±10.7 pg/ml in the osteoporotic group. The mean serum FSH in the normal BMD group was 54.5±44.1 pg/ml and 81.3±34.2 pg/ml in the osteoporotic group. The mean serum LH level in the normal BMD group was 53.1±41.2 and 75.1±26.1 pg/ml in the osteoporotic group. The mean T and Z score were lower in the osteoporotic group. FSH and LH levels significantly differed across menopause stages in that those who were post-menopausal had higher levels compared to those who were pre- or peri-menopausal. Both hormones, FSH and LH, showed weak negative correlations with BMD level, but not E2. There were significant negative correlations between FSH and Speed of Sound (SOS) (r=-0.16; p<0.01), and between osteoporosis with age (r=-0.30, p<0.05) and number of childbirths (r=-0.14 p<0.05). DISCUSSION: Osteoporosis is a significant problem with associations to hormone levels in post-menopausal women. In our study, mean serum estradiol levels decreased with age, and the mean FSH and LH levels were higher in women of later menopausal stage. Further study is warranted to investigate the bone related studies to establish better statistical references among Mongolian women.