Nutrition is MORE important to get right in wrestlers than just about any other sport. This is largely due to the energy requirements of a wrestler in this anaerobic sport. Plus, the weight cutting element coupled with month after month of yo-yo dieting make “proper” nutrition planning even more important.
Iowa High School Athletic association has lots of information about nutrition including a few specific articles about wrestling and healthy weight loss for wrestlers.
Maximizing Wrestling Performance Handout – National Wrestling Coaches Association