Exercising can affect only one or several muscle groups. There has been an opinion widely spread that exercising several muscle groups at the same time will not increase the muscle mass the way that would happen with focusing one group at the time. But that is just wrong. Perhaps the process will be somewhat slowed down, but the end effect will be the same. And time is not lost, it is actually saved, because one exercise covers several body regions.
Muscle mass increase requires constant increase in lifted weight; actually, this is essential for activating the mentioned bulking up. At one point, the organism becomes used to lifted weight and that decreases the energy used for the workout and also decreases the wanted results. Building muscle mass is not the only thing that needs to be done, there is also fat reduction, and elimination of excessive water, with muscle toning. Obviously, a lot has to be done and there are some regions of the body that simply cannot be perfected so easily. Those are abdominal region, gluteal area, entire back, legs etc. Each of those requires special attention in order to be developed properly.
If there is extra fat present in those areas, it should be eliminated with the help of cardio exercises. Cardio workout is excellent for fat burning process and even though it might not seem that it targets some specific area, it actually affects the entire body. Focused muscle mass increase also burns fat, but with weaker intensity. Some of the exercises that should be done include running, swimming, cardio aerobics etc. There are also some more specific forms that are helpful. For example, glute ham raise is excellent for that specific region. It is performed with a help from workout station and it positions the ankles, feet and lower thighs in a required position. Barbell can be used for additional muscle growth effect and the exercise is performed with raising torso from lower position until body is upright and then it is lowered down.