There could be numerous factors in why some people don’t get results from exercise. One could be they are doing the same routine over and over again. Our bodies adapt fairly quickly to our workouts and we don’t see the best results. You should change your workouts every 4-6 weeks. Second many people don’t change their eating habits. Proper nutrition in the key to transforming your body. You should eat 5-6 small meals a day to keep your metabolism running hot. Your meals should consist of lean proteins and carbs. There are good carbs out there. Such as wheat pasta, oatmeal, brown rice, yams. Don’t forget your fibrous carbs, such as broccoli ect. Eat plenty of fresh vegetables and limit your fruit intake to two pieces a day. First two meals because of the high fuctose levels. Maybe they have a medical condition impeading their weight lose. Hypothyroidism for example. People with hypothyroidism can actually do everything right and still gain weight. Their bodys are not producing the proper levels of T3 and T4. It is treatable with medications. Synthoid and Armour are a few examples. If you are doing everything right and still no change try to get a full blood work test done. Talk with your doctor about your concerns.