Understanding Exercise and Weight Loss

How would you explain to a person who suddenly starts running a lot in hopes of getting in shape fast that he would benefit from emphasizing resistance training or swapping out running for traditional strength training if his main goal is body composition change and fat loss? He has also complained about some recent small nagging aches and pains in the feet and muscle soreness from all the running. This question is based on the episode "How To Get The Most Value Out Of All Your Exercises To Build Muscle Long Term | Mind Pump 2143" and the clip "Running and Skill." It is also based on episode 111, "How to look better naked by losing fat without counting calories with Sal Di Stefano," and the clip "Cardio Misconceptions."