Planks

Plank has two common meanings in everyday use: a wooden board and a core-strength exercise. As a piece of timber, a plank is a long, flat piece sawn from a log and used in construction, flooring, and furniture. Planks vary in length, width, and thickness, and may be rough-sawn, planed smooth, or finished with coatings. Typical thicknesses range from about 12 to 50 millimeters (roughly 1/2 to 2 inches), with lengths from about 1 meter up to several meters. Wood types include softwoods such as pine, fir, and spruce for general purposes, and hardwoods such as oak and maple for durability and appearance. Outdoor planks may be treated to resist decay, and engineered products such as laminated veneer lumber or multi-ply planks are also common.

In construction and carpentry, planks are used for flooring, decking, paneling, walls, fencing, and as structural elements. They can be solid boards or part of engineered products. The term can also refer to planks cut for specific finishes, such as tongue-and-groove flooring, or to historic wide-plank flooring common in older houses.

The plank exercise is a popular isometric core workout. It is performed by supporting the body on forearms or hands while maintaining a straight line from head to heels. Key muscles engaged include the abdominals, obliques, glutes, shoulders, and back. Proper technique emphasizes a neutral spine and hips aligned with the rest of the body; avoid letting the hips sag. Beginners often start with 20 to 30 seconds and increase hold time gradually, incorporating side planks and other variations for progression.

Etymology traces to Old English planke, referring to a flat board; planks have been used in ships and buildings for centuries.