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.