The next time you go to the gym to workout with weights or machines, it is important you distinguish the difference between “working” and “isolating” a muscle. Most people spend time working a muscle when in fact what they should be doing is isolating the muscle since isolating the muscle is what produces the best results.
Jogging and running are examples of “working” a muscle. Both demand the entire body to work in order to do, but neither of them actually call on one specific muscle group under a focused, concentrated, intense demand in order to execute. Consequently, neither one of these could be considered an “isolation” exercise for any specific muscle group.
This concept also extends into free weight training and machine training where it is more relevant. When you do a bench press, the primary muscle you are working is the chest, but the triceps and the shoulders, particularly the anterior (front) deltoid, are helping you with the movement and therefore “working”. The goal is to “isolate” the chest (pectorals), and while you are also “working” the chest, you are more accurately trying to isolate it.
Another example in contrast to this is doing pull ups, and this is an exercise where this differentiation can come in handy as many people have difficulty isolating the muscles in the back. When you do a pull up, a bent over row, or a cable row of any kind your goal is to isolate the back muscles, but too many people have what is called “synergistic dominance”, which prevents them from achieving the isolation they need to build and strengthen their back. The synergists in this case are the biceps and arms. While doing the movement, when the biceps are working in assisting the pulling movement, they are not considered the prime movers or the muscle that is supposed to be working the most. Rather, the primary movers are the latissimus dorsi, the rhomboids, and the erector spinae.
In order to “isolate” these muscles you must be able to feel the contraction of them during each repetition. This requires the concentration the best and most professional bodybuilders use to maximally engage the muscle. The best thing to do to allow for this isolation to happen is to first retract the scapulae (the shoulder blades) before calling on the biceps to begin the pulling movement. This scapular “squeeze” is a two-inch move that ensures that the back muscles have already engaged prior to the biceps taking over. When this occurs, in following through on the movement, it is easier to isolate the muscles in the back you are working throughout the full range of motion, ensuring you can achieve maximum “isolation”. If you do not obtain this isolation, then you will merely be “working” the back muscles, and that is not going to be good enough to trigger results, including building muscle, gaining definition, and strengthening the back.
There are more examples of exercises all over the gym where optimal results will require you to not merely work a muscle, but isolate it to achieve the best results. With machinery equipment, if you don’t possess a full control of the primary muscle you are trying to use and change, you will lack isolation and only be working it. This will not be sufficient to produce results. It will once again allow your synergistic muscles to dominate, and in this domination they will only be “worked”, not isolated. Hence, no serious definition, strength, or size or these muscles will be gained at any significant levels.
Isolation is the key to transforming the shape of the muscles. While working the muscles can generally strengthen and change them at a mild degree, without isolation the definition, lines, striations, and curvature of the muscle you want to train will always be limited. The goal of any great bodybuilder is to be able to fully isolate the muscle that they are targeting, and the best bodybuilders not only succeed in doing this, they also master perfect form and the exercises well enough that they can even target and isolate specific parts of the specified muscle (for example, they can hit the upper part of the chest with total isolation, and they can hit the outside sweep or inside sweep of the quadriceps directly by manipulating their focus and form).
The reason why you may be only seeing halfway, minimum results with your weight training in shaping your body is likely because you are only “working” the muscles as opposed to isolating them. One of the best tricks to ensure you are isolating the muscle as opposed to just working it is to hold the contraction of the movement for at least 2-3 seconds and squeeze the muscle at that point. This works best in single joint movement exercises such as those that target the biceps, triceps, and abdominals, but it can also be equally effective when training the back, chest, and legs. Rather than rushing through the movement moving up and down or back and forth at a rapid pace, the abrupt pause at the contraction point of the movement with intense concentration for a few seconds and a squeeze of that muscle ensures slid isolation of that muscle group. It ensures that the muscle fibers are overloaded, isolated, and broken down in a way that will trigger their reshaping and defining.
While working a muscle is still a part of overall athletic activity and fitness, isolating a muscle is what really triggers the best shape of the muscle and overall results. By gaining total control over your posture and coordination during a movement, you can use your mind to control your form, which will enable you to better connect to the muscle you are trying to train, and by controlling this muscle throughout the movement with concentration, you can start to achieve better results by placing more stress on that particular muscle on your exercises. This is sometimes referred to as “concentration” exercises, or “mind to muscle”.