A plank is a flat, rectangular piece of wood or other material, often used in construction and woodworking. It can vary in thickness and length, making it suitable for various applications, such as flooring, furniture, and structural support. Planks are typically cut from trees and can be made from different types of wood, including pine, oak, and maple. In fitness, a plank refers to an exercise that involves holding a position similar to a push-up, with the body straight and supported by the forearms and toes. This exercise strengthens the core, shoulders, and back. It is commonly used in workouts for improving stability and overall body strength.