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Abstract: Tinius, RA, Blankenship, M, Maples, JM, Pitts, BC, Furgal, K, Norris, ES, Hoover, DL, Olenick, A, Lambert, J, and Cade, WT. Validity of the 6-minute walk test and Young Men's Christian Association (YMCA) submaximal cycle test during midpregnancy. J Strength Cond Res 35(11): 3236-3242, 2021-Submaximal exercise testing can be a feasible alternative to maximal testing within special populations to safely predict fitness levels; however, submaximal exercise testing has not been well-validated for use during pregnancy. The purpose of this study was to determine the concurrent validity of the 6-minute walk test (6MWT) and the YMCA submaximal cycle test (YMCAT) to predict V̇o2max in physically active women during midpregnancy. Thirty-seven (n = 37) pregnant women (22.1 ± 1.4 weeks' gestation) and 10 (n = 10) nonpregnant women participated in the study. Subjects completed a graded maximal treadmill test at 1 visit to measure maximal oxygen consumption (V̇o2max), and then subjects completed the 6MWT and YMCAT in randomized order during a separate visit. The predicted V̇o2max from each submaximal test were compared with the measured V̇o2max from the treadmill test to assess the validity of these tests during pregnancy. Among pregnant women, predicted V̇o2max from the YMCAT was not correlated to the measured V̇o2max (r = 0.14, p = 0.42), and the predicted V̇o2max from the 6MWT was only moderately correlated (r = 0.40, p = 0.016) to the measured V̇o2max. Among nonpregnant women, the predicted V̇o2max values from both the YMCAT and the 6MWT had strong correlations with the measured V̇o2max values (YMCAT: r = 0.71, p = 0.02; 6MWT: r = 0.80, p = 0.006). Neither test demonstrated concurrent validity among the pregnant sample. The main finding is that the YMCAT is not a valid method to estimate V̇o2max during midpregnancy (likely due to physiological changes in heart rate [HR] during pregnancy). The 6MWT has potential to be used clinically for estimating fitness as actual and predicted values did positively correlate, and it is not dependent on HR responses to exercise. However, if a precise measure of fitness is needed, then neither test appears to have strong validity for use during midpregnancy., (Copyright © 2019 National Strength and Conditioning Association.)

Background: Exercise during pregnancy and breastfeeding after pregnancy both positively influence a number of infant outcomes. However, whether physical activity during late pregnancy and breastfeeding postpartum influence motor development in the offspring at 4 months of age is unknown. Research Aim: The purposes of this study were to investigate the relationships between several important modifiable factors (i.e., maternal physical activity during late pregnancy and breastfeeding after pregnancy) on infant motor development at 4 months of age. Materials and Methods: Thirty-three women-infant pairs participated in this prospective longitudinal study. Maternal physical activity was assessed during late pregnancy with wrist-worn accelerometers for 7 consecutive days. Surveys were provided to determine infant feeding practices and other variables that could influence infant motor development. A pediatric board-certified physical therapist assessed infant motor development at 4 months using the Alberta Infant Motor Scale. Results: Infants who were exclusively breastfed had the highest motor development percentiles when compared with those whose mothers were supplementing with or using formula exclusively (exclusive breastfeeding: 64.3 ± 20.1, combination of mother's own milk and formula: 43.5 ± 5.0, exclusive formula: 31.5 ± 15.1, p  = 0.001). No associations between physical activity levels during late pregnancy and infant motor development percentiles at 4 months were found (sedentary time: r  = -0.057, p  = 0.75; light activity: r  = -0.074, p  = 0.68; moderate activity: r  = -0.094, p  = 0.60). Conclusions: Infants who were exclusively breastfed had higher motor development percentiles at 4 months of age than those infants whose mothers supplemented with or used formula exclusively. Physical activity levels during late pregnancy were not related to infant motor development percentiles, which suggests that physical activities do not appear to be harmful to infant motor development.

Triclosan is an antimicrobial agent which is widely used in household and personal care products. Widespread use of this compound has led to the elevated concentrations of triclosan in wastewater, wastewater treatment plants (WWTPs) and receiving waters. Removal of triclosan and formation of triclosan-methyl was investigated in activated sludge from a standard activated sludge WWTP equipped with enhanced biological phosphorus removal. The removal was found to occur mainly under aerobic conditions while under anoxic (nitrate reducing) and anaerobic conditions rather low removal rates were determined. In a laboratory-scale activated sludge reactor 75% of the triclosan was removed under aerobic conditions within 150 h, while no removal was observed under anaerobic or anoxic conditions. One percent of the triclosan was converted to triclosan-methyl under aerobic conditions, less under anoxic (nitrate reducing) and none under anaerobic conditions., (Copyright © 2011 Elsevier Ltd. All rights reserved.)