Racial and ethnic differences in physical activity among mothers of young children: 2011–2018 NHANES

BACKGROUND: American women tend to reduce physical activity (PA) during the transition to motherhood. Their main barrier to participation in PA is lack of time due to new/increased parenting and housework responsibilities. Because there are known racial/ethnic variations in time spent on housework among American women, their PA changes during the transition to motherhood might also differ by racial/ ethnic background. This study aimed to compare PA between American mothers of young child(ren) under age 5 years (YC) and American women without children by their racial/ethnic background. METHODS: Secondary data analyses were conducted using 2011–2018 US National Health and Nutrition Survey data. The study sample included 4,892 women aged 20–45 years (Asian n = 760; Black n = 1,162; Hispanic n = 1,324; White n = 1,646). Participants completed a Physical Activity Questionnaire that asked about participation in transportation and leisure-time moderate- and vigorous-intensity PA (MVPA; minutes/week). Multivariable regression analyses were conducted to compare MVPA among women living without children and with YC (no older children) in each of the racial/ethnic groups. RESULTS: Overall, the prevalence of physical inactivity, defined as zero minutes of MVPA in a typical week, was 43% (95% CI = 38–49%) vs. 32% (95% CI = 29–35%) among women living with YC vs. without children. The adjusted odds of physical inactivity for women living with YC, compared to women living without children, was significantly higher among Asian (OR = 2.08 [95% CI = 1.37–3.17]) and White women (OR = 1.63 [95% CI = 1.11–2.38]), while it was statistically insignificant among Hispanic and Black women. Among women who reported participating in MVPA, Asian women living with YC had 35 fewer minutes/week of MVPA than their counterparts living without children (p = 0.06), while other racial and ethnic groups showed no significant differences. CONCLUSIONS: American mothers of YC were less likely to engage in transportation or leisure-time MVPA, compared to those living without children. This association was particularly strong among Asian women. The study results suggest that a PA reduction in the transition to motherhood may be particularly large among Asian American women, calling for targeted efforts for PA promotion among Asian American mothers of YC; e.g., culturally-tailored community-based physical activity programs for Asian American mothers. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12905-023-02591-x.