You have been given a death sentence. You have been diagnosed with ALS (Lou Gehrig’s disease), a fatal motor-neuron disorder. You will gradually lose muscle function until there is no function left. How long do you have? On average, three to five years, with most of that time spent becoming increasingly dependent on others, in every way.
What is your response? If you are Cooper Meacham, age 39, you decide to run the Boston Marathon. To have even a ghost of a chance of doing this, however, you will need to gain muscle function between now and race day at the same time you are involuntarily losing it. You will need to approach every moment of your life, every aspect of every moment of your life, as if there was no tomorrow.
Why would anyone try to do this? As we follow Cooper on the grueling course from Hopkinton to Boston, we learn the reasons, and find ourselves increasingly conflicted between wanting to cheer this grievously afflicted man on and wanting him to stop. If he does not stop, we come to realize, he will die. If he does stop, there will be no tomorrow.