Your basketball team has been playing twice a week since late October. It is now the winter holidays and you have some time off. Instead of resting, you practice frequently so that your skills are sharp when the season starts in January. What is a situation in the American Revolution similar to this one?

The Americans taking up winter quarters at Valley Forge is similar in the sense that they were drilled in European-style tactics by the Prussian Frederic von Steuben and emerged a better army in the spring of 1778. The time before Valley Forge was bleak, as the Americans had lost Philadelphia to the British and many in Congress wanted Washington fired. At Valley Forge, the men waited in huts and were at the mercy of a government unable to supply the men with adequate food or clothes.  
The analogy of your situation as a basketball player and the men at Valley Forge falls short. While you may get better during your break and may even receive extra coaching, hopefully you are not starving. The metaphor of Valley Forge has long been used by sports teams who are going through a tough time, but it is important to remember that right before the colonists went into winter quarters, the situation for America did indeed look hopeless.