Ditto on the snacks. I have found that very brief, but, relatively frequent breaks seem to help keep both the old and young guys moving at a better overall pace. A quick energy bar and a swig of water or gatorade goes a long way. Chomping on some gorp, yeah, that's always good, especially if it has an appropriate dose of M&M's and/or Toll House bits (semi-sweet) sprinkled in among the nuts and dried fruit; after all, without chocolate, life itself would be impossible.