Software:Time trial

In many racing sports, an athlete (or occasionally a team of athletes) will compete in a time trial (TT) against the clock to secure the fastest time. The format of a time trial can vary, but usually follow a format where each athlete or team sets off at a predetermined interval to set the fastest time on a course.

In cycling, for example, a time trial can be a single track cycling event, or an individual or team time trial on the road, and either or both of the latter may form components of multi-day stage races. In contrast to other types of races, athletes race alone since they are sent out in intervals (interval starts), as opposed to a mass start.^[1][2] Time trialist will often seek to maintain marginal aerodynamic gains as the races are often won or lost by a couple of seconds.^[3]

In cross-country skiing and biathlon competitions, skiers are sent out in 30 to 60 second intervals.^[4]

In rowing, time trial races, where the boats are sent out at 10 to 20 second intervals, are usually called "head races."^[5] Head races are typically held in the fall, winter and spring seasons. These events draw many athletes as well as observers. In this form of racing, rowers race against the clock where the crew or rower completing the course in the shortest time in their age, ability and boat-class category is deemed the winner.^[6]

In many forms of motorsport, a similar format is used in qualifying to determine the starting order for the main event, though multiple attempts to set the fastest time are often allowed.^[7] In rallying, the special stages are run in a time-trial format. Other forms of time trials in motorsport include hill-climbing and qualifying.^[7] A similar race against the clock or time attack is often part of racing video games. Time attack is a type of motorsport in which the racers compete for the best lap time. Each vehicle is timed through numerous circuits of the track. The racers make a preliminary circuit, then run the timed laps, and then finish with a cool-down lap. Time attack and time trial events differ by competition format and rules. Time attack has a limited number of laps, time trial has open sessions. Unlike other timed motorsport disciplines such as sprinting and hillclimbing, the car is required to start off under full rolling start conditions following a warm up lap in which they will have to accelerate out as fast as possible to determine how fast they enter their timed lap.