How do secondary headaches help us learn more about primary headaches?

A headache is secondary when it is caused by another condition. The term is used to distinguish this type of headache from the primary headache disorders like migraine, tension-type headache, or cluster headache. Many medical conditions can cause headache, but there are usually clues in the medical history or examination to suggest secondary headache.

Explanation:

Primary headaches could be causing secondary ones. Like an aftershock.

creating amino acids is the answer

no, because those are both different running competitions. while distance runners train their legs and their lungs to run long amounts of time, the sprinters are training their legs and their lungs to give all they have in the little amount of area they need to cover. the brain also plays a huge part in all of this.

the brain is the only thing in your body that sends messages to your body telling you to run. if you are a long distance runner and you have the mind set of a sprinter, you will not get anywhere. if you have a long distance mind set and you have to run 200m in 20 seconds then you will not make it in time.