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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.

The relationship between metabolic flexibility (MF) and components of metabolic disease has not been well-studied among African American (AA) females and may play a role in the higher incidence of chronic disease among them compared with Caucasian American (CA) females. This pilot study aimed to compare the metabolic response of AA and CA females after a high-fat meal. Eleven AA (25.6 (5.6) y, 27.2 (6.0) kg/m2, 27.5 (9.7) % body fat) and twelve CA (26.5 (1.5) y, 25.7 (5.3) kg/m2, 25.0 (7.4) % body fat) women free of cardiovascular and metabolic disease and underwent a high-fat meal challenge (55.9% fat). Lipid oxidation, insulin, glucose, and interleukin (IL)-8 were measured fasted, 2 and 4 h postprandial. AA females had a significantly lower increase in lipid oxidation from baseline to 2 h postprandial (p = 0.022), and trended lower at 4 h postprandial (p = 0.081) compared with CA females, indicating worse MF. No group differences in insulin, glucose or HOMA-IR were detected. IL-8 was significantly higher in AA females compared with CA females at 2 and 4 h postprandial (p = 0.016 and p = 0.015, respectively). These findings provide evidence of metabolic and inflammatory disparities among AA females compared with CA females that could serve as a predictor of chronic disease in individuals with a disproportionately higher risk of development.

To combat maternal morbidity and mortality, interventions designed to increase physical activity levels during and after pregnancy are needed. Mobile phone-based interventions show considerable promise, and BumptUp® has been carefully developed to address the lack of exercise among pregnant and postpartum women. The primary goal of this pilot study was to test the potential efficacy of BumptUp® for improving physical activity among pregnant and postpartum women. A randomized controlled clinical trial was performed (N = 35) with women either receiving access to the mhealth app or an educational brochure. Physical activity and self-efficacy for exercise data were collected at baseline (in mid-pregnancy) and at three additional timepoints (late pregnancy, 6 and 12 weeks postpartum). For moderate-to-vigorous physical activity, a clear trend is observed as the mean estimated difference between groups increases from −0.35 (SE: 1.75) in mid-pregnancy to −0.81 (SE: 1.75) in late pregnancy. For self-efficacy for exercise, the estimated difference of means (control–intervention) changed from 0.96 (SE: 6.53) at baseline to −7.64 (SE: 6.66) in late pregnancy and remained at −6.41 (SE: 6.79) and −6.70 (SE: 6.96) at 6 and 12 weeks postpartum, respectively. When assessing the change in self-efficacy from mid-to -ate pregnancy only, there was a statistically significant difference between groups (p = 0.044). BumptUp® (version 1.0 (3)) shows potential for efficacy. Pilot data suggest key refinements to be made and a larger clinical trial is warranted.

Rachel A Tinius,1 Kristin Yoho,1 Maire M Blankenship,2 Jill M Maples3 1School of Kinesiology, Recreation, and Sport, Western Kentucky University, Bowling Green, KY, 42101, USA; 2School of Nursing and Allied Health, Western Kentucky University, Bowling Green, KY, 42101, USA; 3Department of Obstetrics and Gynecology, University of Tennessee Graduate School of Medicine, Knoxville, TN, 37920, USACorrespondence: Rachel A TiniusSchool of Kinesiology, Recreation, and Sport, Western Kentucky University, Bowling Green, KY, 42101, USATel +1 270-745-5026Email Rachel.tinius@wku.eduBackground: Metabolic dysfunction after pregnancy may have serious consequences for a new mother. The purpose of the study was to characterize basic changes that occur in metabolic profiles from late pregnancy through 4– 6 months postpartum. A secondary purpose was to determine metabolic factors that may be contributing to postpartum weight retention.Methods: Participants (n=25) came in for 2 visits: late pregnancy (∼ 34 weeks gestation) and postpartum (4-6 months). Resting metabolic rate (RMR), respiratory quotient (RQ), and substrate oxidation values were assessed for 15 minutes during fasted conditions. Blood was drawn and skinfold anthropometry was performed to assess additional outcomes (inflammation, insulin resistance, lipid profiles, body composition). The participants completed a number of surveys that examined other lifestyle and demographic data of interest. At the postpartum visit, additional assessments regarding sleep and breastfeeding habits were administered.Results: RMR was lower during postpartum (1517.2± 225.1 kcal/day) compared to pregnancy (1867.9± 302.6 kcal/day) (p< 0.001), and remained lower when expressing RMR per kg body weight (postpartum: 22.3± 2.7 vs pregnant: 23.7± 3.4 kcal/kg, (p=0.034). Relative RMR (RMR per kg body weight) was negatively correlated to insulin resistance (HOMA-IR) during postpartum (r=− .463, p=0.034). Maternal HOMA-IR, inflammation (CRP), triglycerides (TAG), and carbohydrate oxidation were all positively correlated to postpartum weight retention (HOMA-IR: r=0.617, p=0.004; CRP: r=0.477, p=0.039, TAG: r=0.463, p=0.040; Carbohydrate Oxidation: (r=0.469, p=0.018).Conclusion: Metabolic rate is lower during postpartum compared to pregnancy, and may be connected to insulin resistance. Maternal insulin resistance, inflammation, blood lipids, and substrate metabolism are all related to postpartum weight retention.Keywords: postnatal, metabolic rate, insulin resistance, inflammation

African-American (AA) women have elevated predominance of inflammatory diseases concurrent with local inflammation resulting in compromised metabolic function. The purpose of the study was 2-fold: 1) to examine the gene and protein expression of pro- and anti-inflammatory cytokine secretion by peripheral blood mononuclear cells (PBMC) obtained from AA and Caucasian-American (CA) women in response to an acute high-fat meal; and 2) to explore the influence of race (AA vs. CA) on PBMC reactivity. Ten AA and 11 CA women consumed a high-fat meal with baseline and 4 h postprandial venous blood draws. PBMCs were incubated for 3 h then messenger RNA expression and supernatant protein concentration was used to examine inflammatory profiles. All women had a postprandial increase in interleukin (IL)-8 gene expression, IL-8 protein concentration, and tumor necrosis factor alpha (TNF-α) protein concentration (P < 0.05). AA women had a postprandial increase in IL-6, IL-8, and TNF-α protein concentration (P < 0.05). AA women had higher postprandial IL-1β protein concentration and IL-8 gene expression compared with CA women (P < 0.05). Our data uncovers the specific impact of race and time on pro-inflammatory PBMC (IL-1β, IL-6, IL-8, and TNF-α) expression profiles in response to an acute high-fat meal challenge. Novelty: African Americans have higher predominance of inflammatory disease. We explored the potential race impact on peripheral blood mononuclear cell reactivity in response to a meal. A pro-inflammatory response to an acute high-fat meal with race impact was observed possibly contributing to health disparities impacting African-American women.

The aim of this study was to determine the relationships between maternal metabolic flexibility during pregnancy and neonatal health outcomes. Percent change in lipid oxidation (before and after a high-fat meal) was calculated as the measure of “metabolic flexibility”. Neonatal adiposity was assessed within 48 h of delivery by skinfold anthropometry. Metabolic flexibility (r = −0.271, p = 0.034), maternal HOMA-IR (r = 0.280, p = 0.030), and maternal body mass index (r = 0.299, p = 0.018) were correlated with neonatal subscapular skinfold (i.e., measure of neonatal adiposity). Clinical Trail Registration Number: NCT03504319. Novelty: This is the first study to link maternal metabolic flexibility, body mass index, and insulin resistance during pregnancy to neonatal adiposity at parturition.

Introduction Women who are pregnant in rural communities are disproportionally impacted by obesity and sedentary behavior, and this could be related to having negative beliefs about exercise during pregnancy, leading to inactivity. The purpose of this study was to identify self-reported beliefs about exercise among pregnant women in a rural community. Methods Pregnant participants (N = 70) between 8 and 16 weeks' gestation were recruited from an obstetric clinic serving a rural population. An open-ended questionnaire addressing beliefs about exercise and based on the constructs of the theory of planned behavior was administered. Descriptive survey results were analyzed by calculating means and frequencies. Open-ended responses were assessed by inductive content analysis. Results Commonly reported advantages of exercise during pregnancy included improved perinatal health outcomes and weight management. Commonly reported disadvantages included an increase in fatigue and concerns for maternal and fetal safety. Common facilitators of exercise included access to resources, free time or a decrease in demands from work, and support systems including family and friends. Common barriers to exercise included a lack of time, physical changes including feelings of nausea and fatigue, and lack of access to resources. Discussion This study was the first to report beliefs about exercise during pregnancy in a rural setting. Responses in the current study suggest potential gaps in knowledge of evidence-based information regarding physical activity during pregnancy. Beliefs as well as reported barriers and facilitators of physical activity during pregnancy were similar those reported in other populations. In addition, access to resources (or lack of) appears to be an important facilitator (or barrier) among women in rural settings; thus, developing strategies designed to overcome this barrier, specifically in rural areas, is critically important. Future intervention strategies need to be tailored specifically to the needs of women living in rural areas.

Rachel Tinius,1 Cathryn Duchette,1 Sia Beasley,2 Maire Blankenship,3 Nancy Schoenberg4 1Exercise Science, Western Kentucky University, Bowling Green, KY, USA; 2Anthropology, University of Kentucky, Lexington, KY, USA; 3Nursing and Allied Health, Western Kentucky University, Bowling Green, KY, USA; 4Behavioral Science, University of Kentucky, Lexington, KY, USACorrespondence: Rachel TiniusMailing Address: Exercise Science Program, School of Kinesiology, Recreation, and Sport, Western Kentucky University, 1906 College Heights Blvd, #11089, Bowling Green, KY, USATel +1 270-745-5026Fax: +1 270-745-6043Email rachel.tinius@wku.eduBackground: Mobile health technology offers the opportunity for women to engage with physical activity promotion programs without many of the barriers commonly associated with exercise during and after pregnancy (eg, childcare concerns, rigid schedules, fear of doing harm to fetus or self, access to fitness facilities, uncomfortable with body in front of others) which may be particularly useful in under-resourced rural environments. We conducted the first known study on perspectives of pregnant women, postpartum women, and obstetric healthcare providers in a rural setting on needs related to the development of a mobile app designed to increase physical activity during pregnancy and postpartum.Methods: Focus groups and in-depth face-to-face personal interviews were conducted with 14 pregnant women, 13 postpartum women, and 11 healthcare providers in a rural community. Semi-structured questions utilizing constructs of the Health Belief Model were used to identify barriers, facilitators, and other influences on physical activity during pregnancy and postpartum. Recordings of all in-depth interviews and focus groups were transcribed and standard content analyses for qualitative data were conducted.Results: Rural women and healthcare providers expressed several key perspectives about and recommendations to promote physical activity during and after pregnancy. Broadly, these perspectives encapsulated two main themes: 1) physical activity as critical for weight control and 2) the need for evidence-based exercise information. Key desired features of this app identified include goal setting/progress tracking, evidence-based exercise guidance tailored to specific time points of pregnancy and postpartum, social support via community-based forum, symptom tracking, time-efficient workouts, and push notifications.Conclusion: The perspectives identified by participants should be utilized when designing mobile health physical activity mobile apps for pregnant and postpartum women in rural areas.Keywords: pregnancy, postpartum, exercise, mHealth, app, rural

The purposes of this pilot study were to describe changes in breastmilk lipid content in response to an acute bout of moderate intensity exercise and to explore maternal metabolic health factors, including metabolic flexibility, which may impact this change. A cross-sectional, observational, pilot study design was performed in 14 women between 4 and 6 months postpartum. Whole body fasting lipid oxidation was assessed, a standardized high-fat breakfast was consumed, and lipid oxidation was again measured 120-minutes post-meal. Metabolic flexibility was determined by comparing the change in lipid oxidation before and after the meal. Women completed 30-minutes of moderate intensity treadmill walking 150-minutes post-meal. Breastmilk was expressed and analyzed for lipid content before and after exercise. Overall, there was no significant difference between pre- and post-exercise breastmilk lipid content (pre-exercise 59.4±36.1 g/L vs. post-exercise 52.5±20.7 g/L, p=0.26). However, five (36%) women had an increase in breastmilk lipid content in response to the exercise bout, compared to nine (64%) that had a decrease in breastmilk lipid content suggesting inter-individual variability. The change in breastmilk lipid content from pre- to post-exercise was positively correlated to metabolic flexibility (r=0.595, p=0.03). Additionally, post-exercise lipid content was positively correlated with body mass index (BMI), body composition, and postpartum weight retention. Preliminary findings from this pilot study suggest that metabolic flexibility and maternal weight status may help explain the inter-individual changes in breastmilk lipid content in response to an acute bout of moderate intensity exercise.

Women in rural settings are at increased risk for adverse pregnancy outcomes. One potential way to improve pregnancy outcomes in rural settings is through physical activity promotion. However, given the disparities in prenatal care, women in rural areas may not receive information from their health care provider regarding physical activity during pregnancy. Therefore, the purpose of this study was to examine patient and provider communication in a rural setting (both patients’ and providers’ perspectives) regarding physical activity during pregnancy. A mixed methods study was performed among patients and providers in an obstetrical practice in a rural setting. During early pregnancy, patients were asked questions about their current physical activity levels and intentions for physical activity during their pregnancy. During late pregnancy, patients completed a survey regarding communication from their obstetric provider about exercise during pregnancy. Providers responsible for the patients’ prenatal care were surveyed regarding communication with patients about physical activity. Seventy-one pregnant women and five providers participated. 58.2% of patients reported their provider did not discuss physical activity during pregnancy with them at all. Meanwhile, all providers (100%) reported discussing physical activity with all of their patients. Similarly, only 21.8% of patients reported their provider discussed the benefits of exercise during pregnancy, while 100% of providers reported telling their patients about the benefits of exercise during pregnancy. Our study suggests ineffective patient-provider communication regarding physical activity during pregnancy in a rural setting. Improved communication strategies could reduce disparities in health outcomes among pregnant women in rural settings.