My immune system better kick it up a notch . Despite a slight cough , I had a great run this morning . Jballs , my long lost running friend who has been sucked into the abyss of natural gas exploration and the exceedingly exorbitant work days it demands , actually met me for a 6 mile run around town . The cool temperature kept the pace brisk , and we ended up running an extra 1/2 mile . Both of us felt great after the run . I 've got 34 miles on the schedule this weekend ( two runs--24 and 10 ) , and I guess that 's going to be the M.O.

Question: Why is the narrator feeling energized all of a sudden ?
Answer: Running has helped .They love their work .None of the above choices .They love their work hours .