Buffer Than Buff: Quest for Bulk Up

In one of the houses in the Survival Area, there is a man who is always training. On the front of his house, there is a challenge scrawled in bad hand-writing:

If you can best me in my weights training, then I will gladly help one of you Pokémon Bulk Up. I am waiting for you inside.

Seems pretty simple. So, if you wish to take him on, just say so as you enter the Area.