Track and field is a sport that involves running, jumping, and throwing. Meaning using the whole body. The track is shaped like an oval and in the center has grass for the field events
An object at rest will stay at rest unless acted upon unbalanced forces. Before a runner starts they have to be in running position and or at rest. Then when the race starts the runner uses an unbalance force to start running
The two opposing reaction are from the runner and the ground, the runner is moving forward as the ground is what the are apposing against, like Newton's third law,