Softball is often thought of as a slower, safer game, but in reality fastpitch softball players throw the ball as hard as they can and many work to improve their velocity. Softball pitchers use an underhand throwing motion, while the other players on the field throw the ball overhand. You can use drills to increase arm strength for underhand or overhand throwing depending on the position that you play.
Throw or pitch the softball from a greater distance than normal. Move back from your catcher as far as you are able to while still getting the ball to the target. Make 10 to 12 throws from the maximum distance and then work your way back in. Try to extend the distance over time, and you will increase your arm strength.
Use weighted softballs as part of your training regimen. Softball coach Gerald Warner suggests using balls up to twice the weight of regulation balls and also using balls that weigh less than the standard 6 oz. The heavier balls build strength, while the lighter balls allow you to teach your arm to whip faster, both of which will increase velocity.
Attach a resistance band, bungee cord or harness to you while you throw or practice pitching. Attach the cord or harness, generally with a belt, around your waist, and secure the other end to a fence or post. Softball coach George Brandt says that using a harnesses is one of the best ways to increase the speed of your pitches. The resistance forces your muscles to work harder during the motion, which increases strength and in turn boosts velocity.
Study and fine-tune your pitching and throwing motions to look for problems with your mechanics. To improve underhand pitching, Warner suggests focusing on a longer stride, pushing off the mound hard and working on snapping your wrist harder at release. These sometimes forgotten little things in a pitching motion can help you increase the speed of your pitches. To improve overhand throwing, focus on using a full throwing motion with the arm traveling in a full semicircle and make sure you get full extension when you release the ball.
No matter how strong your arm becomes, don't sacrifice accuracy for speed. A slightly slower but accurate throw or pitch is better than a faster toss that's off target.
Warm up before performing throwing drills or playing a game, to help prevent arm or shoulder injuries.