A Nutrition and Exercise Lifestyle Intervention Program Participant Choice Approach

Investigators are using a pseudo randomized yoked design and will include two groups: choice of intervention strategy or no-choice. If the individual is randomized to no choice, then the next person would get a choice and the no choice person would be assigned to the group yoked (matched) to the person with a choice. Participants assigned to the choice group will choose one of three intervention strategies provided; either Group A (receiving both nutrition and exercise simultaneously), B (starting with nutrition and receiving exercise sequentially followed by nutrition starting at 25 weeks) or C (starting with nutrition first and then introducing exercise sequentially at 25 weeks). All groups will follow the full NELIP until delivery. Participants in the no-choice group will be yoked (matched) to a participant in the choice group and receive the strategy that their yoked counterparts chose.

Nutrition component of NELIP: This component is a modified gestational diabetic meal plan that has four general goals tailored to the participant: (1) to achieve approximately 2000 kcal of energy per day. The determination of the amount of kcal consumed per day will consider the participant's intake from the dietary assessment. There also must not be a restriction of calories that exceeds 30% of their total energy intake; (2) participants will consume approximately 200-250g/day of carbohydrates, accounting for approximately 40-55% of total energy intake. Carbohydrate intake will be distributed throughout three meals and four snacks daily. The nutritionist will educate participants about the importance of complex and low-glycemic index carbohydrates through the one-on-one session; (3) fat and protein intake will be approximately 30% and 20-30% of total energy intake, respectively; (4) achieve appropriate micronutrient and fluid intake for pregnancy. This will be monitored by a weekly 24 hour food intake record.

Exercise component of NELIP: This is a walking program that comprises of 1 weekly supervised session on a treadmill or outside and participants will be recommended to walk 2 to 3 additional times per week. The walking program will start at 25 minutes per session, 3 to 4 times weekly, and increase by 2 minutes per week until 40 minutes and then maintained until delivery. This will be monitored by a wrist monitoring device. The primary outcome is adherence measured weekly using a published adherence protocol using a point system. Secondary outcomes are participant satisfaction to the program and health outcomes: weekly weight gain, calculated EGWG, and pregnancy outcomes (birth weight length, infant anthropometrics, APGAR scores and delivery complications). At 2, 6 and 12 months of age the maternal-infant dyad will return to the lab and infant morphometric measurements recorded from birth will be repeated.

Inclusion criteria

• between 12 to 18 weeks of pregnancy
• a singleton fetus
• medically screened with the Get Active Questionnaire for Pregnancy to determine eligibility for participation in the exercise component

Exclusion criteria

• inability to walk
• serious medical problems
• high blood pressure
• uncontrolled chest pain
• uncontrolled symptomatic lung disease
• diabetes before pregnancy
• a history of recreational substance use disorder
• any contraindication to exercise
• enrolled in another clinical trial.