The effects of exercise during pregnancy on sleep, low back/pelvic girdle pain, and fetal hemodynamics
Creators: name: McCarthy, Traci
Publisher: name: No Publisher Supplied
Year: 2023

description: A women’s body goes through many physical changes throughout pregnancy that can lead to sleep impairments, low back pain, and decreased activity. Sleep disturbances associate with increased risk for depression, delivery complications, excessive gestational weight gain, and postpartum weight retention. Low back pain/pelvic girdle pain (LBP/PGP) disrupts sleep, limits mobility, and has a negative impact on quality of life. Although poor sleep and low back pain are common during pregnancy, less research has focused on the benefits of exercise for these outcomes. The goal of this dissertation is to determine if exercise during pregnancy is beneficial for sleep and reducing low back/pelvic girdle pain (Aims 1 and 2) and examine the safety of strength training during pregnancy (Aim 3). Two systematic reviews were conducted to determine the effects of exercise during pregnancy on sleep and low back/pelvic girdle pain, respectively (Aim 1). Results support prenatal exercise for reducing the amount of self-reported sleep disturbances (2 RCT’s n=115; IV -0.53, 95% CI -0.90, -0.16,) and improving sleep quality (3 RCT’s n=316; IV -3.21, 95% CI -3.82, -2.60). When evaluating pain, most exercise interventions, regardless of mode, found positive effects on LBP/PGP compared to control. Additionally, adding in frequent stabilization exercise with a combination of regular physical activity appears to be effective for decreasing LBP/PGP. Although the results of these reviews demonstrated that exercise is beneficial for sleep and pain outcomes, most studies relied on subjective measurements of sleep, pain, and physical activity. Objective measurements of these constructs would provide additional support for these findings. To fill this gap, an observational study was conducted to compare sleep and low back/pelvic girdle pain between women who did or did not meet the current physical activity guidelines (Physically Active [PA, n=24]: ≥150 minutes of moderate-level activity/week; Non-Physically Active [NPA, n=26: &lt;90 minutes of moderate-level activity/week) during pregnancy. Women were recruited during their second trimester and participated in the two-week study between gestational weeks 28-32. Sleep was measured across 2 weeks with continuous monitoring via actiwatch and daily diary, and low back/pelvic girdle pain was measured using a physical exam and questionnaires. Results showed that PA women had better subjective sleep quality and shorter reported sleep onset latency compared to NPA women (ps&lt;0.05). Objective sleep measurements did not differ between groups (ps&gt;0.05). PA women exhibited lower ratings of back and pelvic girdle disability along with lower fear avoidance behaviors compared to NPA women (ps&lt;0.05). Given these benefits of exercise for pregnant women, in addition to other benefits that prior studies have demonstrated (e.g., lowering risk of gestational diabetes), it is alarming that only 19% of women meet the current physical activity guidelines. Safety concerns related to exercise, particularly strength training, contribute to this lack of participation and low physical activity levels. Currently, there is a paucity of research examining the safety of resistance exercise in pregnancy. Thus, for Aim 3, an observational study was conducted to measure perceived exertion, maternal heart rate, fetal heart rate and placental blood flow during strength training at three increasing intensities in women at the beginning of their third trimester (28-32 weeks gestation). Participants (n=37) performed strength exercises for 3 sets of 8 repetitions increasing from 50% to 75% to 85% of their 8-reptition maximum. Perceived exertion was based on self-report after each set, maternal heart rate was measured via heart rate monitor continuously during the session, and fetal heart rate were measured using doppler ultrasound. Maximum fetal heart rate following exercise averaged 156.2 BPM  8.3, 90% CI [153.9-158.5 BPM] and was not outside the safety bounds set by the ACOG. When outcomes were compared between physical activity groups, the PA group lifted heavier weights for all six exercises (ps&lt;0.05) but had a similar maximal maternal heart rate and fetal heart rate response following each exercise (ps&lt;0.05). Thus, resistance exercise did not adversely impact maternal or fetal outcomes. In conclusion, exercise performed during pregnancy can have positive effects on sleep and pain. Achieving the recommended 150 minutes of moderate intensity physical activity associated with better sleep quality, less low back and pelvic girdle disability, less fear avoidance behaviors, and better cardiovascular measures when compared to non-physically activity women. Additionally, performing moderate to vigorous body-weight-loaded resistance exercise did not lead to adverse maternal or fetal responses. Results from this study can help to better inform health care practitioners, fitness professionals and women in general on the benefits and safety of exercise throughout pregnancy.