HOW SWIMMING AFFECTS CARDIOVASCULAR FUNCTION AMONGST INDIVIDUALS WITH DOWN SYNDROME VS TYPICALLY DEVELOPING INDIVIDUALS

Abstract

Cardiovascular differences in Down syndrome (DS), the most common chromosomal disorder, mark a key difference between this population and typically developing (TD) individuals. This study, conducted by the Memory Development & Disorders Lab at the University of Arizona, investigated how swimming affects cardiovascular function amongst participants with DS compared to their TD peers. Previous studies have used treadmill tests, in which children and young adults with and without DS would have their heart rates recorded continuously while on a treadmill for a set number of minutes (Bahiraei et al., 2023). However, very few studies have been conducted using more accessible forms of exercise, such as swimming. Through a generous donation from a family in Tucson, support from the Lejeune Foundation, and a partnership with the UA Campus Recreation Center, participants with DS and TD participants engaged in 8 free 30-minute swimming lessons over 2 weeks. Prior to these 2-week swim lessons, individuals attended a session in the lab and collected baseline heart rate data over a 60-minute sedentary time period. This study also evaluated memory and executive functioning prior to and during swimming, but this thesis will focus on the cardiovascular results. 23 participants with DS, ages 5-26, and 25 TD mentally-age-matched peers, ages 5-12, participated in the study. The mode of collection for heart rate was continuous using MotionWatch goggle clips. At the beginning, middle, and end of the lesson, Finger-tip Pulse Oximeter measures were collected for all participants as well. Results indicated that maximum, average, and percentage maximum heart rate significantly increased as a result of swimming in both groups, suggesting that swimming is an effective form of cardiovascular exercise in this sample. Secondly, TD participants had significantly higher maximum, average, and percentage maximum heart rates than DS participants while swimming but not at baseline, suggesting differences in heart rate between the two groups in response to swimming.