Functional is a synonym of Running. Running is related to Retreat. 
one thing you do when you Hike is Sweat. you are likely to find Water in/at/on Sweat. Water is related to Office. you are likely to find Lighting in/at/on Office. 
Functional <--Synonym--> Running <--RelatedTo--> Retreat 
Hike --HasSubevent--> Sweat <--AtLocation-- Water <--RelatedTo--> Office <--AtLocation-- Lighting 