Compare a humans changes during exercise to the changes that occur a during a dogs exercise when it is exposed to a hot environment

A human body, just like a dog's, will sweat. Dogs will pants and sweat through the pads of their feet to cool down, and human will sweat through their foreheads, armpits, etc.
Dogs will tend to, in hot environments, lay on the floor or where the surface is cooler. Since they cannot simply strip their clothing to keep cool they tend to find cool surfaces, fans, sources of air, etc. to keep cool from the heat.