To bridge the gap is to catch up with the rider or group that is ahead, typically after they have picked up speed or broken away. One can do it on their own or accompanied, and it is incredibly hard work and effort.
One of the best tactics in bike racing is bridging. The riders must maintain their pace and conserve their energy, timing when they make the bridge so that they don’t waste their efforts. This is crucial in racing over longer distances where timing, wind, and co-ordination between riders count for much. Bridging can win a stage for the rider or turn the race. It is a favored tactic that intelligent riders execute nicely and can alter the outcome in competitive racing.