Question: What happens when you go down a hill does your temperature go back down again ?

Dan Gordon answered on 14 Mar 2018:

What a great question. This is slightly complicated so bear with me. When we do any exercise we generate heat, mostly through our muscles where 75% of the energy that is used in a contraction is lost as heat. So when we run up a hill we need more powerful contractions so would produce more heat than when on a flat surface. However when you go down a hill the way our muscles work changes. Now they are trying to act as brakes which means that they use almost no energy (can explain why if you wish). This means that less heat is produced from the muscle and so temperature would appear to fall.
However when we go down hill we are in essence recovering, because we are using less energy this means that you start to now replace the energy that you lost when going up hill. Guess what, this produces heat. So in the first instance going down hill would produce more heat than going up hill. But were you to go down more than you went up temperature would eventually begin to fall because you have recovered from the up hill work.
Hope this makes sense.