A marathon mentality means that you are in something for the long haul. You are not going to walk away or leave before the job is finished. Here, “long haul” means a long period of time or a great distance. For example, long haul truckers drive their large vehicles over great distances. Okay, now let’s talk about sprinters. If you have a sprinter’s mentality, you attack a problem with short, fast bursts of energy. There is no need to pace yourself. There’s isn’t time! A sprinter’s mentality means you do not hold back. You do something with all the energy you have. You can do this because you know the project (or problem) will only last a short time. Now, a person can have both a mentality of a marathon runner and a sprinter. It may depend on the situation or project. However, some people may be more one kind of person than the other.

What is the mentality of a sprinter?
attacking a problem with fast bursts of energy
taking your time dealing with a problem
taking lots of rest and coffee breaks
being confused as to where to begin
What does mentality mean?
an attitude or way of thinking
the weight of an individual
the smoothness of a surface
confusion
A marathon mentality means that you are in something for the long haul.
the long haul
the short term
a very brief time
a temporary period