Help with moving blocks

Hey guys, I am currently trying to create a game where you use moving blocks to get from one point to another. The only problem i have right now is the fact that the blocks move when I jump on them. How can I make these blocks move in a straight line with out moving when I make contact with it.

To make the blocks move i am currently using all ways to motor (X and forward) to velocity (X, Y and forward).

try making the block have a rectangular shape (item submenu)