Is heat really a home field advantage???

I saw someone post earlier this week about how the heat supposedly gives us a home field advantage....but does it really or does it only serve to wear our team down after months of training in it during the summer months?  I just cant see how it doesn't contribute to our injury issue. Check out a map of the the southern teams, over the past 10 years (its gotten considerably warmer in the past 10 years) all the southern teams have been losing teams except those that play in domes, and its especially bad with teams that have a good deal of humidity to deal with as well.thoughts?