What is in this image? Describe it as if you were explaining it to someone from the 15th century.

This picture shows a group of athletes at the starting point of a competition, wearing streamlined attire for swift movement. They are bent at the waist, positioned on supports that touch the ground, somewhat reminiscent of a marksman steadying before releasing an arrow, but these devices assist in launching them forward instead of steadying a bow. Their clothing is tight to reduce the wind''s grip, much like how a swimmer in your time might oil their skin to slip through the water more easily.Beside the competitors is a tiered structure where spectators would sit, akin to the grandstands you might see at a jousting tournament, though constructed from materials you would not recognize, smooth and uniform. There’s an obscured board aloft which likely displays scores and timings, using technology far beyond hourglasses and sun dials, it instantaneously updates information for the viewers.The setting is refreshing; there are mountains akin to those you might find in the distance beyond a meadow, giving a naturalistic boundary to the scene. The competitors are on an elongated path that has clearly defined boundaries and a smooth surface, facilitating their race without impediments of rugged terrain or obstacles.