Nothing wrong with having some normal fat on you most of the time, BUT for championship and olympic racing you must engineer your body fat down to almost nothing in order to run fast.
Very precise dieting is necessary to drop all the fat and even some lean mass, while still hitting that sweet spot where you still maintain necessary strength and speed but have dropped 5, 10, or 20 pounds of unnecessary mass.
If you are in the 5k final, a 5 lb difference in weight can be monumental--medal or no medal, or make the final or dont make final.
A 10 lb difference basically moves you from front pack to rear pack.
Almost gaunt and extremely cut is what wins.[/quote]
Yes, MEN can get their body fat to very low levels-single digit body fat%. However, women NEED sufficient body fat for their body to ensure regular menstruation occurs.