The major joints of the human body include the knee joint, ankle joint, the spine and neck joints, the shoulder joint and the shoulder girdle, the elbow joint, the radio-ulna joint of the forearm and the wrist joint.
Anatomical Description Related to the Sternum
The shoulder joint, a ball, and socket joint, is laterally placed to the sternum. This joint is linked to the sternum by the clavicle (collar bone), forming a sternoclavicular joint (at the sternum) and acromioclavicular joint (at the shoulder/gleno-sphenoid joint). The pectoral girdle is posterior to the sternum and is also joined to the sternum by the clavicle at the acromioclavicular joint.
Posterior to the sternum, the pectoral girdle is strengthened by muscles, e.g., the trapezius. Other joints of the upper limb, i.e., the elbow joint, wrist joint, and radio-ulna joints are appendage joints which are lateral and not directly connected to the sternum (Human Anatomy and Physiology Course, para.3)
The joints of the lower limbs are in the same mid-saggital/longitudinal plane to the sternum though not directly joined to it. They are joined indirectly to the sternum through the spine and the ribs. On the other hand, the joints of the spine are posterior to the sternum either superiorly, e.g., neck or inferiorly, e.g., the lumbosacral joint. The spine and its joints are in the same plane (midsagittal) as the sternum (Human Anatomy and Physiology Course, para.3).
Exercises which Use Major Joints and other Multi-Joint Exercises
Exercises which involve the spine include the neck work exercises, for example, forward flexion, lateral flexion, and extension. The knee, on the other hand, uses dead lifts and even other dumbbell exercises. The elbows and the shoulders mainly use extensions of the triceps muscles, military press, and curls. Other ranges of motion exercises are also applied to these joints, especially during flexibility exercises (Brian Mac Sports Coach, para. 6).
These range of motion exercises include flexion and extension of the hip joints, adduction and abduction at the hip joint, leg curl, hip flexion and extension, flexion and extension at the elbow joint and knee joint, eversion and inversion at ankle joint, nodding at the neck joint, inward and outward rotation at the shoulder joint and other degrees of motion exercises (Single-Joint and Multi-Joint exercises, para. 3).
Multi-joint exercises (which involve more than three major joints) involve a wide musculature hence they stimulate muscles of nearby joints causing movement. For example, exercises such as incline press, bench press, military press, and other pulling exercises stimulate the movement of the wrist joint, elbow joint, and girdle by stimulating the surrounding musculature (Single-Joint and Multi-Joint exercises, para. 2). Other exercises which involve more than three joints of the human body include the squat, leg press, and lunges.
According to Hatfield, different dumbbell exercises involve the movement of more than one joint in the body. Of the above exercises, those which cause movement of more than three joints include one arm dumbbell table curls where dumbbell training starts in a position with the arm partially bent and the weight at the chest.
This moves such joints as the shoulder joint, the shoulder girdle, elbow joint, and wrist joint. These muscles are also caused to move by the one arm dumbbell bent press. The lying on a single arm dumbbell support and then standing up also causes multi-joint movement. These joints include the shoulder joint, the girdle, the spine, and the neck (Hatfield, 2005).
The front lunge walking with dumbbell causes the knee joint, hip joint, spine, girdle, and ankle joint to move. During the calf raises method of dumbbell training, the calf muscles cause the ankle joint to extend and to span of the knee joint and also the movement of the spine and hip joint. Dumbbell flies, the dumbbell bench press and the inclined dumbbell bench press cause movement of the elbow joint, shoulder joint, wrist joint, and the pectoral girdle (Hatfield, 2005).
Lessons learned and Impacted on my Practice
As a personal trainer, the above information is important to me in determining the specific kinds of exercise to apply which in turn depends on the type of joint and the range of motion that the joint can allow.
The lesson learned about multi-joint exercises is key to my practice, especially to achieve the desired effect, e.g., on various muscles during training. Moreover, this knowledge is critical, especially in clients with joint conditions as it helps me to exercise caution when applying these exercises so as not to harm sick joints (Sudy, 1991).
The knowledge and lesson on the use of dumbbells for multi-joint movement, as explained by Hatfield, are also very important as it disregards the need for me to acquire expensive machines. In such cases, I may resort to training my clients and friends or family using dumbbells to meet their training needs as they are cheap and affordable.
The lesson of movement of joints as a result of protagonist and antagonist action of different muscles is very important to me as forces that affect the muscle also affect the bone and vice versa (Hatfield, 2005)
Brian Mac Sports Coach: Flexibility and Mobility. Web.
Hatfield, F. (2005). Fitness: The complete guide to dumbbell training. International Sports and Sciences Association.
Single joint and multi joint exercises. Web.
Sudy, M. (1991). Personal trainer’s manual. San Diego. American Council on Health Education.