There is almost no research on hydration and performance...or recovery issues like muscle soreness. But I have some preliminary research stuff that was covered on this topic at a recent sports training conference I went to, so I will look at it again and post about it later.

Lena - i realize transfer across athletic disciplines is often pooh-poohed here, but I know there is quite a science (art?) to recovery in the areas of weightlifting/general training. I realize that a lot of this is just an opportunity to sell supplements like creatine and glutamine, BCAA's, etc. That said, there are studies that show that consuming liquid carbs and protein within 30 minutes after exercise help reduce soreness and/or increase recovery.

But if you're really convinced about temps, then a possible hypothesis is that the increase in temperature means you have to grip more to generate friction which means you're just working a bit harder than normal. Small switchs in exercises force the body to adapt and adaptations create soreness. It's the difference between doing normal pullups and wide grip pullups (not that anyone should ever do pullups ).

Aerili - i just punched "soreness" and "hydration" into google scholar and found 5 promising articles in the first 2 pages - all fairly recent.

My guess would be that, even though you're consuming plenty of water, you're still coming up short on things like electrolytes, sodium and potassium. Water doesn't help much if you're body doesn't have the things it needs to use water. Try stuff like Camelbak Elixir or Nuun tablets, Gu, Cliffshots, and all of that junk. I have good luck with the Elixir tabs, and I think they taste the best.

*edited to include the first letter of my post*

FWIW, when I was racing bikes, I could function just fine at 95 degree races, hour after hour after hour. I just drank a lot more, probably more than double. I think I probably popped salt tablets too, I remember using those a lot.

Anyway, I felt that as long as I kept enough fluid going through me, the only problem was that I was hot.

I find it impossible to get enough fluid while climbing. Like I said earlier, it seems to affect my strength, not my soreness.

One thing, also bike related, not climbing. I work on the pedicab, the rickshaw. It's hours and hours of riding a heavy bike. It's easy to forget to drink doing that. When I spend 10 hours on the bike with barely a sip, I feel way tired the next day. I actually feel hung over, even though no alcohol was consumed.

In my experience, hydration is pretty much the magic formula.