Nevner hvor mye diafragma og pustemuskler har å si for kontroll og stabilitet i bevegelse. Bla. kjernemuskulatur og intraabdominalt trykk.
Respiratory-muscle exercises are used not only in the rehabilitation of patients with respiratory disease but also in endurance training for ath- letes. Respiration involves the back and abdominal muscles. These muscles are 1 of the elements responsible for posture control, which is integral to injury prevention and physical performance.
The results suggest that respiratory-muscle exercise straightened the spine, leading to good posture control, pos- sibly because of contraction of abdominal muscles.
In competitive sports, the spine of young athletes can have excess thoracic kyphosis and lumbar lordosis because it is the conduit for transferring mechanical power between the upper and lower extremities during rapid and forceful movements.1
Under the influence of these forces, athletes have much degeneration of the intervertebral disks,2 and the loss of disk height with denaturation is associated with increased spine curva- ture.1 Thoracic kyphosis and lumbar lordosis contribute to back pain.3
The loss or increase of lumbar lordosis correlates well with the incidence of chronic low back pain.4,5 In addition, thoracic kyphosis leads to shoulder pain.3
Spinal-alignment control is essential for preventing various injuries. Align- ment depends on muscle strength and balance, muscle tightness, and skeletal structure.9
The trunk muscles are grouped into 2 categories: global and local stabilizers.10 The global stabilizers com- prise superficial muscles such as the rectus abdominis and longissimus muscles, and the local stabilizers are deep muscles, for example, the transverse abdominal and multifidus muscles.10 Cholewicki et al11 reported that thecontraction of local stabilizers is indispensable to trunk stability; that is, the trunk becomes unstable in the case of contraction of global stabilizers alone. The unstable trunk increases stress to the ligament and bone that control the end of motion and cause pain such as back pain.12
Respiratory-muscle exercises are used in the reha- bilitation of chronic obstructive pulmonary disease18 and endurance exercise for athletes.19 The muscles comprise the diaphragm, intercostal muscles, and the accessory muscles of respiration.20 The accessory muscles of res- piration consist of several of the trunk muscles, includ- ing local stabilizers. Therefore, this study focused on exercises for the respiratory muscles, which have the advantage that the load can be accurately set by regulating frequency and depth of breathing.
Increased spine curvature is responsible for low back pain4,5 and swim- mer’s shoulder,6 so respiratory-muscle exercise may prevent these dysfunctions.
Because muscle strength for trunk flexion was noted to increase only in the exercise group, we conclude that the exercises strongly affected the abdominal muscles. Abe et al32 reported that the transverse abdominal muscle is the most powerful in the abdominal muscle group with respect to respiration. The transverse abdominal muscle may have been specifically targeted in this exercise. This important muscle is a key local stabilizer.
Contraction of the transverse abdominis increases intra-abdominal pressure, which leads to lumbar
straightening.33 In addition, a rise in intra-abdominal pres- sure presses the rib cage upward and effectively allows the extension of the thoracic vertebrae.34
In addition, we attribute the decrease of thoracic curvatures to a stretching effect on the thorax. In a previous study, Izumizaki et al35 reported that thoracic capacity and rib-cage movement were changed by thixotropy, which is the exercise of maxi- mal expiration from maximum inspiration. The stiffness of the rib cage leads to thoracic kyphosis.3 In this study, repetitive deep breathing resolved the stiffness of the rib cage and straightened thoracic kyphosis. This process may be responsible for altering the spinal curvature.
These training methods require a long period of 12 weeks for improvement. By contrast, our intervention period was 4 weeks, so spinal alignment may be improved in a much shorter period.