When going through Airborne training as an ROTC cadet in August, a long, long time ago, the Black Hats made sure everyone was hydraded and run through the showers 2-3 times per day. When you are soaking wet from a cold shower, 95 degrees is actually comfortable.
Last night I was trying to figure out when I went to Jump School, I came up with July, but had forgotten some courses and now think it was closer to the end of August, I thought it was pretty hot then, but I had already been spending all my time at Ft.Polk and then Fort Sill, so it was nothing new.
Sadly, despite all precautions, there are a number of military personnel who die each year in training accidents. Back in 1991, General (then Lt. Colonel) David Petraeus was nearly killed when a soldier tripped during a live-fire exercise and accidentally shot him in the chest.
Back during WW2, thousands of airmen perished in flight training accidents. The Zachary Taylor National Cemetery in Louisville contains dozens of mass graves from the transport aircraft crashes that occurred in the region. Bowman Field was one of the primary transport pilot training facilities in the country, as well as the site of the main production plant for the Curtiss C-46 Commando. They would take young pilots, some with less than twenty hours of flight time, and place them behind the wheel of a brand new C-46. Unfortunately, some of these aircraft had construction flaws (due to the hasty assembly times necessitated by the war) and would suffer severe problems while in flight. If they had an experienced pilot with a couple hundred hours of flight time, they might have recovered; but with a rookie pilot who usually only has a few dozen hours, the results were often catastrophic.