Dirty Mind?

Oh how I miss thee
With thy fast pace
and with thy slow pace
Leaving my breath shallow

Every time we partake
I go weak in the knees
As sweat falls
My muscles seize

My vision is blinded
As we go along
My heart rate is growing
Though I stay going strong

Until at last I give in
Though this ride, it was stunning
I make my way home
After a long time of running