To increase the speed of your fastball, you will need to focus on a few key areas: mechanics, strength and conditioning, and mental focus.

First, make sure your mechanics are sound. So focus on the following areas:

1. Start with a robust and balanced base. Your feet should be shoulder-width apart, and your weight should be evenly distributed. This will give you a solid foundation to generate power.
2. Use your lower body to drive your pitch. This will help you generate more force and velocity. Your legs and hips should do most of the work, with your upper body providing support and balance.
3. Keep your arm relaxed, and your wrist snaps at the moment of release. This will help you maintain control and prevent the ball from tailing or sailing.
4. Follow through with your pitch. After releasing the ball, your arm should continue moving toward your target. This will help you maintain your momentum and add velocity to your pitch.

By focusing on these areas, you should improve your mechanics’ soundness and increase your fastball’s speed.

Next, work on building up your strength and conditioning. This will help you generate more force behind your pitches, which will, in turn, increase the speed of your fastball. You can achieve this through weight training and functional exercises targeting the muscles used in pitching.

Try the following exercises:

1. Medicine ball slams: Stand with your feet shoulder-width apart and hold a medicine ball in front of your chest. Quickly extend your arms and slam the ball into the ground as hard as possible. This will help you build explosive power in your legs and hips.
2. Box jumps: Stand in front of a box or bench and lower into a quarter squat. Quickly explode upward and jump onto the box, landing softly with bent knees. This will help you develop lower body power and improve your balance.
3. Plyometric push-ups: Start in a standard push-up position and lower your chest to the ground. Quickly push up and clap your hands together before returning to the starting position. This will help you build upper body strength and power.
4. Single-leg Romanian deadlifts: Hold a dumbbell in one hand and stand on one leg. Keeping your back straight, bend at the waist and lower the dumbbell towards the ground. This will help you develop balance and strength in your legs and hips.

Incorporating these exercises into your training routine will help you build up your strength and conditioning, which will, in turn, increase the speed of your fastball.

Finally, focus on your mental game. Here are a couple of tips I feel are good common practices:

1. Develop a strong routine and stick to it. This will help you stay focused and calm on the mound.
2. Take deep breaths and stay relaxed. This will allow you to maintain control of your pitches and prevent them from getting wild.
3. Visualize success. Imagine yourself throwing a perfect pitch and hitting your target. This will help you stay focused and confident.
4. Stay positive, and don’t let mistakes affect you. Every pitcher makes mistakes, but the best pitchers can move on quickly and focus on the next pitch.

This will help you stay relaxed and avoid rushing your pitches, which can lead to losing control and velocity.

By working on these areas, you should increase the speed of your fastball and become a more effective pitcher. 

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