According to reports in the media, Mr. Bechler had the following risk factors for heat stroke:
a prior history of heat illness episodes while in high school - which heightens the probability of reoccurring incidents;
a family history of sudden death following exercise (his half-brother died of an aneurysm at the age of 20 after overheating from playing baseball);
a history of hypertension and liver problems;
he had not eaten solid food for a day or two, in an apparent attempt to lose weight;
he was apparently not adequately acclimatized to training in the heat and humidity of South Florida;
it appeared that he was wearing two or three layers of clothing during workouts, again, in an attempt to lose weight;
he was overweight and did not have a high enough fitness level to make it through conditioning drills; and,
he was allowed to exercise until he collapsed with a core temperature reportedly of 106° F before being removed from the field.
It has been extensively documented that untrained, overweight, and unacclimatized people who perform excessive exercise in heat/humidity are at great risk of heat illness and heat stroke—particularly if they have become dehydrated and are trying to lose weight quickly.