Having attended outdoor training and PT on a fair number of occasions, I have heard the phrase, "stay hydrated," from countless instructors. With the weather hitting the 90's this week, that type of advice is warranted. The CDC offers many hot weather tips for avoiding heat related problems. Their best advice is prevention...take a look at the CDC link HERE for helping to prevent heat related illness. Additional tips can be found on the Red Cross website HERE.
If you or someone you know is experiencing symptoms of heat stroke or heat exhaustion, dial 9-1-1 and seek medical aid immediately.