Through a recent conversation with a coworker I was reminded of a technique my JV Volleyball coach once told our team: when you're feeling overheated and/or exhausted run the inside of your wrists under cold water as it will help you cool off. At the time it seemed like it would fall into the too-good-to-be-true category, but you know what? I tried it at a match at Danville High School in VA when we were playing inside their un-airconditioned gym for a match early in the season. Side note: The fact that I remember the exact moment I used this technique is significant and gives you a little context to the effectiveness.
So, getting back to the conversation, after she jogged my memory in talking about the technique she's trying with an athlete, I was prompted to dig up actual research to see if there is anything besides my own anecdotal evidence to support my experience.
Here's what I found from the British Journal of Sports Medicine article "Effect of a 5-min cold-water immersion recovery on exercise performance in the heat.":
Background: This study examined the effect of a 5-min cold-water immersion (14 degrees C) recovery intervention on repeated cycling performance in the heat. Methods 10 male cyclists performed two bouts of a 25-min constant-paced (254 (22) W) cycling session followed by a 4-km time trial in hot conditions (35 degrees C, 40% relative humidity). The two bouts were separated by either 15 min of seated recovery in the heat (control) or the same condition with 5-min cold-water immersion(5th-10th minute), using a counterbalanced cross-over design (CP(1)TT(1) --> CWI or CON --> CP(2)TT(2)). Rectal temperature was measured immediately before and after both the constant-paced sessions and 4-km timed trials. Cycling economy and Vo(2) were measured during the constant-paced sessions, and the average power output and completion times were recorded for each time trial. Results Compared with control, rectal temperature was significantly lower (0.5 (0.4) degrees C) in cold-water immersion before CP(2) until the end of the second 4-km timed trial. However, the increase in rectal temperature (0.5 (0.2) degrees C) during CP(2) was not significantly different between conditions. During the second 4-km timed trial, power output was significantly greater in cold-water immersion (327.9 (55.7) W) compared with control (288.0 (58.8) W), leading to a faster completion time in cold-water immersion (6.1 (0.3) min) compared with control (6.4 (0.5) min).Economy and Vo(2) were not influenced by the cold-water immersion recovery intervention. Conclusion 5-min cold-water immersion recovery significantly lowered rectal temperature and maintained endurance performance during subsequent high-intensity exercise. These data indicate that repeated exercise performance in heat may be improved when a short period of cold-water immersion is applied during the recovery period.
As you can see there is good evidence to support the use of cold-water immersion to improve recovery between intense bouts of exercise.
Application:
Consider the full 5-minute immersion of your forearms (not hands) for applications like recovery periods between maximum effort lift attempts, large breaks in a competitive match (soccer, basketball, lax, etc).
If you're short on time, experiment with even just :30 of cold running water on the wrists (like from a water fountain). Personally, I've found this effective.
Regardless, of which variation you choose, you will notice your entire body seems to be operating at a cooler temperature and you actually feel refreshed despite the intense workload you are trying to recover from.