Drafting is a technique where two or more cyclists ride in a close group reducing the overall effect of drag by exploiting the lead cyclists slipstream.
The optimum drafting position is as close behind the leader’s rear wheel as possible, or if there’s a crosswind, slightly overlapping (echelon) can also be helpful.
The lead cyclist also benefits from drafting as the area of negative air pressure behind them (which causes drag) is reduced by the following cyclist.
Drafting reduces air resistance, the primary force opposing cyclists, and reduces energy utilisation by as much as 40%. Furthermore, it has been demonstrated while drafting a cyclist outdoors at 39.5 km/ hour compared with cycling alone results in reductions of ~14% for ˙VO2, 7.5% in HR, and ~31% for expiratory volume (VE).