The sperm are changing chemical energy into kinetic energy.
Chemical energy is defined as the chemical substance’s potential to undergo a transformation through a chemical reaction. So, this type of energy can be transformed to other forms of energy by a chemical reaction.
Kinetic energy, on the other hand, is the energy that an object (structure) possesses due to its motion.
So, in the example above, chemical energy of the glucose is used (by breaking the bonds of this molecule through the chemical reaction) for the formation of sperm’s kinetic energy (necessary for movement).