Athletic heart syndrome (AHS) is a non-pathological condition commonly seen in sports medicine in which the human heart is enlarged, and the resting heart rate is lower than normal. The athletes heart is associated with physiological cardiac remodeling as a consequence of repetitive cardiac loading. Athletes heart is common in athletes who routinely exercise more than an hour a day, and occurs primarily in endurance athletes, though it can occasionally arise in heavy weight trainers. The condition is generally considered benign, but may occasionally hide a serious medical condition, or may even be mistaken for one. Signs and symptoms
Athletes heart most often does not have any physical symptoms, although an indicator would be a consistently low resting heart rate. Athletes with AHS often do not realize they have the condition unless they undergo specific medical tests, because athletes heart is a normal, physiological adaptation of the body to the stresses of physical conditioning and aerobic exercise. People diagnosed with athletes heart commonly display three signs that would usually indicate a heart condition when seen in a regular person: bradycardia, cardiomegaly, and cardiac hypertrophy. Bradycardia is a slower than normal heartbeat, at around 40–60 beats per minute. Cardiomegaly is the state of an enlarged heart, and cardiac hypertrophy the thickening of the muscular wall of the heart, specifically the left ventricle, which pumps oxygenated blood to the aorta. Especially during an intensive workout, more blood and oxygen are required to the peripheral tissues of the arms and legs in highly trained athletes bodies.
It is used in the Duff reaction (formylation of arenes), the Sommelet reaction (converting benzyl halides to aldehydes), and in the Delepine reaction (synthesis of amines from alkyl halides). Explosives
Hexamethylenetetramine is the base component to produce RDX and, consequently, C-4 as well as Octogen, hexamine dinitrate, hexamine diperchlorate and HMTD. Historical uses
Hexamethylenetetramine was first introduced into the medical setting in 1895 as a urinary antiseptic. However, it was only used in cases of acidic urine, whereas boric acid was used to treat urinary tract infections with alkaline urine. Scientist De Eds found that there was a direct correlation between the acidity of hexamethylenetetramines environment and the rate of its decomposition. Therefore, its effectiveness as a drug depended greatly on the acidity of the urine rather than the amount of the drug administered. In an alkaline environment, hexamethylenetetramine was found to be almost completely inactive.Hexamethylenetetramine was also used as a method of treatment for soldiers exposed to phosgene in World War I. Subsequent studies have shown that large doses of hexamethylenetetramine provide some protection if taken before phosgene exposure but none if taken afterwards. Producers
Since 1990 the number of European producers has been declining. The French SNPE factory closed in 1990; in 1993, the production of hexamethylenetetramine in Leuna, Germany ceased; in 1996, the Italian facility of Agrolinz closed down; in 2001, the UK producer Borden closed;  in 2006, production at Chemko, Slovak Republic, was closed. Remaining producers include INEOS in Germany, Caldic in the Netherlands, and Hexion in Italy.