hello. Its a bit specific topic but I can try to help. When you're standing on a balance board, you have to use your core muscles to stabilize yourself. Otherwise, you'll tip right over. I found for example such balance boards
https://itfactory.ca/collections/balance-boards
If you're working in a typical office setting, it's easy to go the whole day without really engaging your core -with the help of a balance board, though, you can strengthen these often-neglected muscles.