The goal of this study is to determine the effectiveness of a mobile exercise app in improving cardiovascular health and motivation to exercise in pregnant women who are healthy, in their 2nd trimester, between 18-45 years age, and do not do exercise currently. The aims of this study are determine i) the effect of a mobile app (BumptUp) to increase motivation to exercise as assessed by questionnaire, and ii) the changes may occur in cardiovascular health outcomes such as increased percent Flow-Mediated Dilation (FMD), Heart Rate Variability (HRV), and decreased Pulse Wave Velocity (PWV) over an 8-week period of intervention. Researchers will compare this to pregnant women who are healthy, in their 2nd trimester, between 18-45 years age, and who will not be using the mobile app (BumptUp) for exercise. Participants who are in the experimental group will be given access to the mobile app (BumptUp) for 8 weeks. Both the control and experimental group will visit the lab for their baseline measurements (study visit 1), followed by two visits at 4 weeks (study visit 2) and 8 weeks (study visit 3) to have their heart rate variability, arterial stiffness (PWV), and vascular function (FMD) assessed. At each study visit, blood pressure, heart rate, height, and weight will also be measured. Additionally, at all three study visits, participants will fill out a questionnaire to determine motivation to exercise.

Inclusion Criteria:

• Age: 18-45 years.
• Pregnant women who are 20-24 weeks pregnant at enrollment
• Sedentary, as defined by completing less than 90 minutes of exercise each week.
• Generally healthy, uncomplicated pregnancies.
• Free of physical limitations that may interfere with alterations in daily physical activity levels.
• Single gestation.
• Have a smartphone
• Under the routine medical care of an obstetrician or certified nurse midwife during their current pregnancy.
• Women speaking English.

Exclusion Criteria:

• Physician diagnosed cardiovascular/ vascular complications (heart disease, high blood pressure, Raynaud's phenomenon etc.)
• Physician diagnosed metabolic diseases (diabetes, hypothyroidism)
• Musculoskeletal injuries (broken bones, back pain, ankle sprain, muscle pull, etc.)
• Medications that may impact blood vessel function such as hypertension medication (Angiotensin converting enzyme inhibitor, Angiotensin receptor blocker, Calcium channel blocker, beta blocker), lipid lowering agents (statins), Nitrates, steroids, etc.
• Complications associated with pregnancy that would be exacerbated by exercise such as lung disease, persistent spotting/bleeding or Placental Previa, premature labor, ruptured membranes, evidence of intrauterine growth restriction, pregnancy induced hypertension or pre-eclampsia, uncontrolled epileptic fits/seizures.
• Smoking within the previous 3 months.

Only pregnant women will be recruited