Stabilizer muscles hold positions. They do not move loads. Overstressing the stabilizer muscles often comes from the fallacy of functional training. Muscles that move limbs laterally classify as stabilizer muscles. Their true function is to prevent lateral movement, not allow it. This means that big muscles, such as the middle deltoid, nonetheless serve as stabilizer muscles. Others include the core, outer hips, inner thighs, trapezius, and neck muscles. The calves also act as stabilizer muscles, though mainly to absorb shock from the foot. This occurs during running and jumping. You can learn some important lessons about proper training if you realize this distinction.
Stabilizers work best through assisting major movements. This means normal actions like running, pushing, pulling, etc. generate power from large muscle groups. Stabilizer muscles only allow for it. This means that abductor / adductor machines, leg raises, sit-ups, hyperextensions, side bends, lateral raises, neck flexion, and other popular exercises do not train these muscles well. These exercises certainly work these muscles, but fail to work them in a way safe on the joints and at their strongest positions. Working the stabilizers with movement invites shearing force. Snapping a pencil with two hands best describes this type of force. Your joints handle this effect anytime a stabilizer works with movement.
The middle deltoid is a stabilizer muscle since it works laterally. The reason for its large size comes from the long distance between the shoulder and hand. This long lever makes even the lightest weight feel very heavy when held far away from your body. That shows why even a meager 15 lb. can feel difficult during a lateral raise. The muscle is not large because it should receive direct exercise. Any exercise you can do that focuses on this, such as a lateral raise or an overhead press, can destroy the shoulder. Instead, simply focus on pushing and pulling horizontally. A horizontal push works the first half of the middle deltoid intensely. A horizontal pull works the back half of the middle deltoid intensely. It stabilizes during all upper body exercises, with certain regions assisting movement as well depending on the exercise. It also works intensely to hold the arm away from your side, such as when holding a heavy object. This prevents your arms from impeding the movement of your thigh. An unusual exercise such as a farmer’s walk, when you carry two heavy objects at your sides and just walk, therefore works the middle deltoid well. Carrying a heavy object some distance represents strength training at its most basic.Trying to work the middle deltoid through movement will only cause pain and discomfort eventually.
The body operates as a functional unit. Do not train it as separate bits and pieces. Bodybuilding developed to isolate muscles. This never considered the function of the joints. This often involves training stabilizer muscles with movement. It may place the body at unusual angles in an attempt to target certain muscle fibers. This causes incredible stress to the joints, with only very few lucky enough to tolerate it. It also likely has not even a slight effect in shaping the muscle differently as well. Joint attachments do not change when you hit a muscle from another angle. Often this only puts some muscles in weaker positions. If you fail to understand this point, then you will likely practice too many exercises that harm your body. This can potentially wear out your joints. It can overtrain you and dilute your effort. This all hampers your results. Instead, cut out the clutter and focus supreme effort on pushing, pulling, and squatting. Your joints will appreciate it. You will grow incredibly strong for any purpose: for speed, to look good, and to function better and more safely. Just imagine your capabilities for growth if focusing on only three big exercises.
The stabilizers already work intensely to brace for heavy exercises. If you want to test them further, simply practice your sport or include athletic movement. Examples include safe unilateral exercises like split squats or simply running sprints. If concerned about the explosiveness during sprinting, slow down with a sled or perform them on a hill. These exercises also condition as well. This helps complement a resistance training program by addressing cardiovascular fitness. Stairclimbing, jumping, and even slow hiking can work the stabilizer muscles. Stability training that often occurs on unstable surfaces only makes exercise dangerous. If needed, develop stabilizer muscles through basic exercises along with athletic motions. Do not make good exercises unstable or work stabilizers with movement.