High Quality Content by WIKIPEDIA articles! Exercise induced pulmonary hemorrhage (EIPH), also known as "bleeding" or a "bleeding attack", refers to the presence of blood in the airways of the lung in association with exercise. EIPH is common in horses undertaking intense exercise, but it has also been reported in human athletes, racing camels and racing greyhounds. Horses that experience EIPH may also be referred to as “bleeders” or as having “broken a blood vessel”. In the majority of cases EIPH is not apparent unless an endoscopic examination of the airways is performed following exercise. However, a small proportion of horses may show bleeding at the nostrils after exercise, which is known as epistaxis.