Breathlessness occurs in the lower part of the ribs bilaterally, sometimes involving the abdomen and back. Breathlessness is usually caused by strenuous exercise without any preparatory activities, and is a manifestation of the lack of oxygen in the muscles of the body, or the inability to catch up with the rhythm of the exercise, leading to spasms of the muscles controlling the respiratory movements, mainly the diaphragm and the intercostal muscles, causing pain in the lower part of the ribs bilaterally, the upper part of the abdomen, and sometimes even discomfort in the back. When the body performs strenuous activities, the skeletal muscles rapidly consume the supply of nutrients brought by the blood, resulting in a short period of oxygen and blood deprivation of the respiratory muscles before the body has compensated for it, and spasms can occur to produce pain. After the appearance of pain, should immediately rest in place, can be slowly deep breathing, with local massage to relieve the symptoms.