Prenatal Exercise and Glucose Regulation

Description

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.

Interventions

• Acute exercises sessions with different exercise types and intensities (Behavioral)
  During both RT sessions, participants will perform eight exercises that will target the whole body. Exercises will be performed using dumbbells at four sets of 10 repetitions, with one minute of rest between sets. The first set will be done with very light weight (warm-up). The next three sets will be the "working sets," done with a weight that will elicit the proper intensity. During AT, participants will use either a treadmill, bike, elliptical, or rower. Throughout the 45-minute session, every five minutes, the participant will report their RPE, and if they report low, speed will be increased by 0.1-0.5 mph until the proper intensity is achieved. Incline/resistance will not be used to modulate intensity, to ensure that there are no mechanical influences on AT that mimic the nature of RT.

Eligibility criteria

Conditions

Locations

• Human Performance Laboratory (HPL) at the University of Central Arkansas — Conway, Arkansas, United States