A chin-up is a strength training exercise that primarily targets the muscles in the upper body, particularly the latissimus dorsi, biceps, and trapezius. To perform a chin-up, an individual hangs from a horizontal bar with their palms facing towards them and pulls their body upward until their chin is above the bar. This movement helps build muscle strength and endurance. Chin-ups can be modified to suit different fitness levels. Beginners may use assistance bands or perform negative chin-ups, where they start at the top position and lower themselves slowly. Regular practice of chin-ups can improve overall upper body strength and contribute to better athletic performance.