What Do We Do At Marshall Personal Training? We change the way you think about yourself in order to change the way you live your everyday life. By working with a qualified personal trainer you will learn to understand the importance of life coaching, nutritional planning and of course correct exercise so that we ultimately change your perception of what you think is normal. We'll do this by making you discover muscles you never knew you had, boundless energy you didn't think you could find and reach personal goals you never thought possible. David Marshall Personal Training David Marshall is the sole owner and principal instructor at David Marshall Personal Training Northampton. David qualified in Sport and Exercise Science and achieved level 3 Personal Trainer status.