A lot of people have suggested good ideas on this thread, and it could be a nutrition thing, but I want to weigh in on rehydration. Be very very careful about rehydrating after long rides or races of 2+ hours in hot/humid conditions. Someone suggested drinking lots and lots of plain water. Drinking too much plain water can lead to hypotranemia, which is uncomfortable to say the least. The ER trip after Vegas last year was enough to convince me to be pretty darn careful about electrolyte balance.
Honestly, recovery is dictated partly by the nutrition you consume and the actions you take after the race. What people forget to mention is that recovery is dictated very heavily by your pre-race fitness. The fitter you are, the faster you recover. Matt Fitzgerald writes some good stuff on this.
The more you push your body, the fitter you will get and the easier it will be to recover from hard training sessions or longer races.
Hope this helps a little.
Max