Tactics are based on drafting. This is where a rider can reduce the effort needed to pedal by following the rider in front very closely. Riding with others in the main field, called the peloton, can save as much as 40% of the energy needed to ride alone. Riders can help each other to ride at high speed, or one rider can sit on a competitor's wheel, forcing him to do more work and get tired earlier. Some teams have a leader, and the rest of the team let him or her draft them to save their energy for the important bit of the race. Drafting is not allowed in individual time trials.