Prenatal Exercise and Glucose Regulation

Gestational diabetes mellitus (GDM) is the most common disease during pregnancy and is characterized by an inability to regulate blood glucose (sugar) levels because of resistance to the hormone, insulin, which is responsible for getting glucose out of the blood. Aerobic training (AT, "cardio," for example: walking) is commonly used to regulate blood glucose levels in similar populations, like diabetics, but another form of exercise known as resistance training (RT, for example: weightlifting), has shown to be just as effective. Further, exercise intensity, regardless of the type, is directly proportional to blood glucose control. However, no study has compared AT and RT exercise modalities or intensity on blood glucose regulation in GDM, even though women with GDM share a similar insulin resistant phenotype as diabetics. Therefore, long-term objective of this study is to compare the effects of exercise type and intensity on glucose regulation and insulin sensitivity after four acute exercise sessions: low intensity RT (LOW-RT), low intensity AT (LOW-AT), moderate intensity RT (MOD-RT), moderate intensity AT (MOD-AT). Researchers will address the following aims: Specific Aim 1: Determine the impact of exercise type and intensity on glucose regulation using continuous glucose monitoring during- and for 24 hours after four acute exercise sessions: LOW-RT, LOW-AT, MODRT, and MOD-AT. Researchers hypothesize that RT and moderate intensity will elicit better glucose control compared to AT and low intensity, respectively. Specific Aim 2: Determine the impact of exercise type and intensity on insulin sensitivity by quantifying the quantitative insulin-sensitivity check index (QUICKI) before and after four acute exercise sessions: LOWRT, LOW-AT, MOD-RT, and MOD-AT. Researchers hypothesize that RT and moderate intensity will elicit greater insulin sensitivity compared to AT and low intensity, respectively.

Inclusion Criteria: * Biological female * Singleton (one fetus) * 24-30-wks gestation * 18-35 yrs old * Sedentary * Conception without the use of assisted fertility treatments Exclusion Criteria: * Existing other metabolic disorders * Currently taking medication or supplements that affect glucose metabolism * Taking drugs, tobacco, or alcohol during pregnancy * Having a contraindication to exercise