Dr. Cody Sipe shares the #1 tip to provide to your mature client. The benefit of function!!! Our clients want to be able to move better so that they can live life the way they want to live it. Cody shares a story about a client that came to us wanting to improve her function. Cody shares the other aspects of function that are important as well. Our functional aging specialist certification provides you with the skills to help improve the function of mature clients. To start working with this population, please check out the Certifications tab at the top of this page.