Infants with Down Syndrome Needed for the Following Study: Understanding and Modeling the Gait Patterns of Individuals with Down Syndrome: New Walkers Background Little research has been conducted examining the walking patterns of toddlers with Down syndrome. But we do know that children with Down syndrome walk later, walk and run slower than typically developing children, have poorer balance control, and tend to have orthopedic problems (e.g. flat feet and arthritic painful joints) with age. Our project will improve the body of knowledge regarding the development and quality of walking patterns, and improve our understanding of how gait is regulated in children with and without Down syndrome. We believe that improved knowledge in these areas may assist in planning effective intervention for toddlers and children with Down syndrome. Participation You and your toddler will come into the motor development lab on two days (within about 1 week) when your toddler has been walking for 3 months and subsequently at 6, 12, and 18 months of walking experience, for a total of eight sessions. Each of the sessions will last approximately 1-½ hours. There is a small risk that your toddler may fall while walking on the treadmill. However, most walking speeds will be slower than overground walking, and you and the lab team will remain very close to and ready to assist your child. Your toddler may experience minimal fatigue while walking on the treadmill. Your toddler will have the opportunity to explore his/her capabilities walking in a new environment. You will have the satisfaction of contributing to the study of the development of motor control in children with and without Down syndrome. Currently there is little information on the quality, efficiency and regulation of walking patterns in toddlers with Down syndrome. This information may assist in planning effective intervention for toddlers and children with Down syndrome. Data Collection You and your toddler will come to the motor development laboratory initially when your toddler has been walking for 3 months and subsequently at 6, 12, and 18 months of walking experience. We will collect data on two separate occasions at each of these times. The purpose of the first day is to help you and your toddler become acquainted with the motor development laboratory and explain the purpose of the study and the procedures involved. We will also collect movement data as your toddler walks along a 5-meter walkway and walks on the treadmill at 75% of his/her overground speed. We will place small reflective markers on both sides of your toddler's head, shoulders, elbows, hips, knees, ankles, and feet. We will also place small sensors on the front and back of the thigh and lower leg and on your toddler's stomach and back in order to record your toddler's muscle activity while walking. Six high-speed cameras will be positioned on each side of your toddler. Your toddler will be asked to walk across the walkway at a comfortable speed, so that we can determine how fast your toddler usually walks. Your toddler will then be taught how to walk on a treadmill. First he/she will step onto the treadmill belt that is not moving. While holding onto his/her hands, we will gradually increase the speed of the treadmill to 75% of his/her overground speed for 3-4 minutes in order to familiarize him/her with walking on a treadmill. You and a lab member will remain close by at all times. Following a brief rest, we will turn on the treadmill at a low speed (40% of her/his overground walking speed). We will gradually increase the speed of the treadmill to 57%, 75%, 93%, and 110% of his/her overground speed. (Your toddler will determine IF we can work with all of these speeds and at what age. We expect to be able to work with the slower speeds at all ages and work up to the 110% over time. YOU will help us decide the rate at which your child progresses in this aspect.) At each speed, your toddler will walk on the treadmill for 2 minutes (30-60 second intervals). Our primary goal is obtaining movement data for the 75% speed condition. You or your toddler may ask us to stop the treadmill at any time. Following the walking trials, we will take body measurements of your toddler. The purpose of the second day will be to collect the same movement data as day one to assure that we get his or her "optimal" performance at each age. If you would like to learn more about participating in one of our studies, please call us at (734) 615-1494 or email us at csdren@umich.edu. When calling, please request Cheryl Drenning and reference the Down syndrome modeling study. All To Participate