The Plank Test is a fitness assessment that measures core strength and stability. During the test, an individual holds a plank position, which involves maintaining a straight line from head to heels while resting on their forearms and toes. The goal is to hold this position for as long as possible without sagging or lifting the hips. This test is commonly used in various fitness programs and is beneficial for evaluating overall body strength. It engages multiple muscle groups, including the abdominals, back, and shoulders, making it a comprehensive exercise for core conditioning.