100%, balance boards help with surfing. Surfing uses a lot core strength. Balance boards help you develop that core strength by way of improving your balance. It’s that easy
There are a few benefits to using a balance board to train for surfing. Balance boards:
The more a balance board mimics what you are doing in the water the more or dry-land training will translate into improved surfing.
For example, you can walk up and down a balance board mimicking walking a longboard. You can also practice smaller movements on the balance board similarly as you would when surfing a short board specifically when you are adjusting you back foot before a big turn.
When you work on your small foot adjustments on a balance board you start to see just how much your body mechanics unintentionally push the board up or down, which will ultimately wastes your physical energy and slows your surfing down.
Using a balance board will help you maintain a steady, flat state on the board. The more you can maintain a steady flat state and not push too much pressure on the nose or tail of the board are the wrong time, the more you keep the board balanced and planeing (maintaining flatness), which will help you keep your speed, giving you the momentum you need to move through your turns.
Simply putting more time into improving your balance (AKA – time training on a balance board) and all of the little core muscles that go into not falling off of balance board, the more stamina, strength and balance you will be able to call upon to make your turns when you are surfing.