The aim of this project is to assess the influence of exercise on pharmacokinetics (PK) and pharmacodynamics (PD) of a single dose of subcutaneously (sc) administered unfractionated heparin (UFH). It is hypothesized that exercise will increase the systemic exposure (PK) and therefore the clinical effects (PD) of the sc administered UFH.

To assess this, healthy male volunteers will be included in a controlled, randomized, crossover study, where they, on four separate days, will have UFH injected sc in the thigh, followed by different exercise interventions (one per experimental day). Blood sampling, with the aim of assessing PK and PD will be performed during the following hours.

Inclusion Criteria:

• Body weight 50 kg or more
• Body Mass Index 18.5-25 kg/m2
• Acceptance of not drinking alcohol for 24 hours before to 24 hours after dosing of study drug
• Acceptance of not performing physical activity for 24 hours before to 24 hours after dosing of study drug
• Signed informed consent form

Exclusion Criteria:

• History or sign of bleeding disorders
• History or sign of kidney disease
• History or sign of liver disease
• Average systolic blood pressure <100 mmHg or >140 mmHg and/or average diastolic blood pressure <60 mmHg or >90 mmHg (average of three measurements performed at screening).
• Daily pharmaceutical treatment
• Contraindication to increased levels of physical activity (10)
• Smoking or other regular use of any form of nicotine products during the study period and the previous 3 months.
• Current or prior participation (within 3 months before screening) in other clinical trials that might affect the results of this study (judged by the investigator).
• Previous treatment with heparins
• Low levels of anti-thrombin (P-antitrombin(enz.) <0,80 kIU/L)