Short Stories with Tragic Endings

I am with a representative of Puma who seems to resemble a cross between
Bear Grylls and Mike Rowe. There is also an old lady there. They are doing an
experiment with Puma's newest shoe, the Cabana Racer, and the representative
gives the old lady a red and orange pair of Puma Cabana Racer shoes. I point
out that I am also wearing my white-black-grey pair and the representative gets
a smile on his face and says "aahh". The old lady puts on the red Pumas and
the test is going to be a race with a race car. The car is yellow and looks quite
fast. The old lady starts running and I run as well. The car is definitely not going
its full speed but it is not going slow either. Somehow we are keeping up with it
but we are not going faster than a normal running pace. We run through a city
for a while, the car had lost us a long time ago, and after a bit we stop, look at
each other, and the dream ends.