Abstract
A slipstream is formed behind an object in downstream. Even in a marathon event, it is possible to use preceding runners as a shield to reduce aerodynamic drag and to carry out physical strength preservation. These preceding runners are called pacemakers, who maintain a lap time of an objected runner. In this research, to confirm the effect of pacemakers' slipstream and their formations, experiments and numerical calculations were carried out in a real Reynolds number and compared with experiments concerning drag and flow field.
