- A dumbbell is a type of free weight used in strength training and resistance exercises. The weights on a dumbbell can be fixed or adjustable, allowing users to customize the load for their specific needs and fitness levels. Dumbbells are a versatile fitness tool that can be used for a wide range of exercises, including arm curls, shoulder presses, chest presses, rows, squats, lunges, and more. They can target specific muscle groups or be incorporated into full-body workouts. They are commonly used for strength training exercises. By lifting and controlling the weights, they help to build and tone muscles, increase strength, and improve muscular endurance.