At the start of a race, a cyclist's velocity is zero because they are not yet moving. However, as they begin to pedal and move forward, their velocity increases. The direction of the velocity depends on the direction in which they are moving.
Acceleration is the rate at which velocity changes over time. In the case of a cyclist at the start of a race, their acceleration would be positive, as they are increasing their velocity. The magnitude of the acceleration would depend on various factors such as the force of the cyclist's pedaling, the mass of the cyclist and the bike, and the friction between the tires and the ground.
As the cyclist continues to pedal, their velocity will increase, and their acceleration may either increase or decrease depending on the external factors that influence their motion. Ultimately, the cyclist's velocity and acceleration will determine their position and speed relative to other cyclists in the race.