During exercise, splanchnic perfusion is compromised, resulting in organ damage in healthy individuals. Improving the availability of NO might result increase splanchnic perfusion and prevent organ damage during exercise.

The gastrointestinal (GI) tract plays an important role in the human body. The wall of the GI system regulates digestion and absorption of nutrients and it also has a very important function as a barrier between internal and external environment. The penetration of harmful substances and microbiota of the GI lumen (external environment) to the systemic circulation (internal environment) depends on this barrier. Previous studies have shown that exercise in healthy subjects provides hypoperfusion of the splanchnic area, resulting in intestinal damage, increased small intestinal permeability and liver damage. Similar splanchnic hypoperfusion occurs in patients with compromised circulation.

During episodes of splanchnic hypoperfusion, the de novo synthesis of nitric oxide (nitric oxide, NO) from arginine is compromised. This impaired NO synthesis may play a role in the development of organ dysfunction during exercise. L-citrulline administration, a precursor of arginine and NO, may result in improved NO availability and organ perfusion, thereby preventing organ damage.

Inclusion Criteria:

• male
• age 18-35 years

Exclusion Criteria:

• not healthy
• use of medication or related products
• alcohol misuse
• smoking