How we walk, sit, stand, and carry our posture during daily activities affects how we move in our sport. It is especially important to learn how to move from the inside to outside of the body. Primarily, this means presenting a posture that permits the most efficient use of the muscles of the hips, legs, and torso (the core). Learning to engage these muscles during flexion, extension, and rotation is central to performing better movements in all sports and begins with proper posture.
Standing with anatomically correct posture begins the process for establishing and enhancing all body lines in swimming. Learning to take this position into the water and maintaining the centerlines of movement will take you further toward improved swimming than just about any technique. In assessing flexibility, mobility, and stability, movement tendencies become evident - you can tell to what extent you use your core muscles in your basic movements. For coaches, assessment can provide teaching moments in which to educate your triathletes how to be more aware of using the core muscles. Practicing functional movements teaches the body to use core muscles deep inside the body to affect movement of the limbs and achieve more efficient technique.
The muscles in the hip region are frequently unstable in triathletes. Notably, the gluteus medius (a muscle that prevents tilting or sagging of the pelvis) is an important pelvic primary stabilizer. When the gluteus medius is weak, other muscles or movements must compensate for the weakness in everyday activities, such as standing up from a chair. This compensation results in less efficient, less functional movements. Over time, the muscular, nervous, and skeletal systems become affected by these repeated less functional movements and sustained faulty postures.
Swimmers who move functionally on land transfer their skills remarkably well into the water, improving in symmetry of swimming motions and performance and reducing the risk of overuse injury. Balanced and symmetrical swimming movement begins in the proximal muscles at the body’s core (below the chest to above the knees), which support the outward, or distal, muscles near the head, arms, hands, legs, and feet. An excellent technique to engage the deep core muscles is to draw in when exhaling to activate these muscles and help stabilize the pelvis, which result in better streamlining and better movements.
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Proximal and distal - swimming from inside to out.
Thus optimal posture on land transfers directly to swimming and eases motor learning in the water. By learning to control your body during flexion (sitting) and extension (standing) through the use of your core muscles, you begin the process of establishing more functional movements. Movements controlled by active engagement and stability from the proximal muscles affect the functionality of the distal muscles during swimming (figure 6.4).