I just spent a solid whack of time in the mountains , six full days out of the last eight hiking in Garibaldi Provincial Park . And I could n't be happier still feeling the burn in my legs . It started last Sunday with a 30-plus kilometre day trip into the Diamond Head area .
According to the above context, answer the following question.
What is causing the narrator to be presently so exhausted ?


They just went off on an excursion .