How do I reinforce my Bouncy Laundry Room Floor?

The Maytag Man has guaranteed me that if I reinforce the floor under my laundry room my front load washer won't "walk" around the room anymore. The machine is made to--I don't know--- dispense it's energy through the bottom he says which has been causing my floor to vibrate excessively which is making the machine move and sound like a hurricane in my home. I am pretty handy, but am at a loss on how to even start this "simple" project. PLEASE HELP ME!!!!! the machine has actually ripped a hole into the new vinyl flooring. I am at my wits end. I have a crawl space.