These tricks currently have no use in a speedrun
There are a few known techniques that can be performed in order to cross bodies of water or lava without falling in. The currently known methods either have no use or they don't allow Link to exit the body of water/lava (see below).
This trick requires multiple frame perfect inputs and is not considered RTA viable.
If Link performs the grabbing animation on a precise frame when walking over water or lava, the animation that would normally cause him to drown or burn can be avoided. Repeating these grabs on the correct frame will allow Link to hover over water or lava indefinitely while still being able to move forward. Unfortunately, this technique does not allow Link to get back onto dry land if the jump out of water animation would be required to leave the water, even if he makes it all the way to the shore. Damage from external sources, such as bombs, do not boost Link onto land either.
Some objects and enemies in the game will make the Hammer recoil when you hit them, knocking Link back a great deal. If you're standing near a ledge, the recoil will cause Link to hover temporarily in the air, allowing Link to cross over lava or water for a short distance.