Previous studies have shown that a decreased blood flow is a risk factor in the occurrence of Achilles tendon (AT) injuries. Based on the current literature, no consensus was reached as to the most solid warming-up of the AT. Therefore, knowledge about activities which increase blood flow in the AT could be useful in the development of a solid warming-up programme for the AT. The aim of this investigation was to define the influence of different kinds of physical activity on the vascularisation of the AT in a healthy asymptomatic population. Subjects performed five activities in randomized order: running, static stretch, dynamic stretch, cycling and rope skipping. The vascularisation of the AT of the dominant limb was measured with the non-invasive oxygen-to-see (O2C) device. Blood flow was measured before, immediately after, five and ten minutes after activity to investigate the duration of the vascular response to activity.

Inclusion Criteria:

• no history of Achilles tendon complaints
• healthy and active adolescents

Exclusion Criteria:

• history of Achilles tendon pain or current complaints
• not healthy or not active population
• children