Here’s how to determine how many miles you should walk per day, according to experts. Meet the experts: Alexander Rothstein, CSCS, ACSM-EP, is an exercise physiologist and instructor for the exercise science program at the New York Institute of Technology. Laura A. Richardson, PhD, a professor of Applied Exercise Science and Movement Science at the University of Michigan School of Kinesiology. Meanwhile, for those younger than 60, step-count benefits didn’t plateau until 8,000 to 10,000 steps. How Many Miles You Should Walk Per Day For Weight LossIf weight loss is your goal, answering this question really shifts to focusing on energy expenditure, both experts agree.