Longer physical exercise duration prevents abnormal fasting plasma glucose occurrences in the third trimester: Findings from a cohort of women with gestational diabetes mellitus in Shanghai

OBJECTIVE: This study aims to investigate the relationship between daily physical exercise (PE) duration and frequency of abnormal plasma glucose (PG) times both during fasting and 2 h after a standard diet in women with gestational diabetes mellitus (GDM). METHODS: We established a cohort involving 878 GDM women. GDM was confirmed by a diagnostic 75-g oral glucose tolerance test. Information was extracted from the delivery records and antenatal checkup forms. Physical exercise information was collected through a questionnaire. RESULTS: Over 80% of GDM women were under 35 years old. An abnormal fasting PG with ≥1 occurrence presented in 742/878 (84.51%), and the abnormal PG 2 h after standard diet with ≥1 occurrence presented in 634/878 (72.21%). Compared to GDM women with ≥4 occurrences of abnormal fasting PG, GDM women with 0 occurrences (odds ratio (OR) = 2.56), one occurrence (OR = 1.94), two occurrences (OR = 2.29), and three occurrences (OR = 2.16) had a higher proportion of PE duration being in the 45–60-min/day group than those in the <45-min/day group, and GDM women also had a higher proportion of PE during being in the 61–90- and >90-min/day group than those in the <45-min/day group. However, the duration of PE was not associated to the number of abnormal PG occurrences 2-h after the standard diet. CONCLUSION: Moderate-intensity PE duration in GDM women was negatively associated with the number of abnormal fasting PG occurrences but not with the number of PG occurrences 2 h after the standard diet.