James W. Lewis is a contributing writer for Exercise.com and a former Command Fitness Leader in the Navy. After retiring from active duty service, he returned to school and obtained a master’s degree in Exercise Physiology. He also has certifications through the American College of Sports Medicine (ACSM). He currently works as a personal trainer at a major northern California university and as an exercise physiologist at a cardiac risk reduction center. His writing credits include American Fitness Magazine, Kraze, Naptural Roots Magazine, and a book titled, Exercises for Older Veterans with PTSD.