Arm Care Velocity Screen

Velocity, accuracy and durability. These are the characteristics that set a pitcher up for success. Without any one of these characteristics, the full athletic potential of a player will be missed. So what is the best way to maximize each of these? The answer is to utilize an assessment based arm care program at regular intervals throughout training and season to identify impairments, fatigue and shortcomings of each individual athlete. Without testing, you’re just guessing.

Pre-Velo Screen

Research has consistently highlighted a number of modifiable risk factors, that predispose a pitcher to an increased risk of injury. Each of these risk factors should be assessed during a pre-velo screen:

Skeletally Mature

Skeletal Maturity in skeletally immature adolescents, the growth plates on the ends of the bones (also known as physis) are still open. This means the athlete is still growing. These growth plates are susceptible to injury, that can have long term consequences.  Injury to the shoulder growth plate is known as Proximal humeral epiphysiolysis or “Little League shoulder”, while injury to the elbow is known as Medial epicondylar apophysitis or “Little League Elbow”. If you are 16 years old or younger, and have x-rays to confirm your growth plates are closed, you are eligible to proceed with a velo program.

IR Strength

Internal rotation strength is shown to be one of the biggest influencers of throwing performance. Pitchers often have greater IR strength on their dominant arm compared to non-dominant arm, as well as increased IR strength compared to non-throwing age matched individuals. If your internal rotation strength is in the bottom 25% of your age group, you will benefit from additional strength work prior to starting a velo program. By following your recommended arm care program and training, you will address this underlying weakness, reduce your risk of injury and likely experience greater performance gains than you would if you jumped into a weighted ball program.

ER Strength

External rotation or posterior cuff strength is responsible for controlling the ball in the socket during layback as well as the deceleration of the arm after release in the throwing motion. Preseason weakness has been shown to be one of the strongest predictors of throwing injuries in not only the shoulder but in the elbow as well. In fact, athletes that suffer UCL injuries have demonstrated a 30% decrease in their ER strength tests prior to their injury. Based on the overwhelming body of research linking ER weakness to injuries in throwing athletes, if your strength falls in the bottom 25% of your age matched cohort, your focus should be on a posterior cuff strengthening program rather than a velo program at this time.

ER/IR Strength Ratio

In addition to an athlete’s raw strength numbers it is important to make sure their strength remains in balance. The nature of throwing mechanics as well as a high volume of pitches naturally increases a pitcher’s internal rotation strength. However, if there is a lack of increased external rotation strength to counter the internal rotators, athletes end up with an increased risk of injury. Research has focused a lot of attention to the ER:IR strength ratio and the role it has in risk of injuries to the rotator cuff, labrum and UCL. If you have greater than a 15% difference between your ER and IR strength, you are at an increased risk of injury, and not appropriate to begin a velo program at this time. Rather than focusing on velocity, it is more important to focus on balance and durability of your arm.

Scaption Strength

Scaption strength plays a key roll in shoulder stability and the ability to transfer power during the throwing motion. Typically scaption strength in a healthy pitcher is slightly stronger on their throwing arm compared to non-dominant arm. During the course of a season, or following heavy workloads, scaption strength has been shown to decrease by 13%. In addition, pre-season scaption weakness was a strong predictor of in-season injury. If your scaption strength test is in the bottom 25% of your age matched players, you are risking injury and decreased accuracy due to poor control at your shoulder joint. Take time to focus on strength and improve your mechanics prior to jumping into a velo program.

Internal Rotation Range of Motion (ROM)

The internal rotation range of motion of the shoulders is often asymmetrical, with less internal rotation occurring on the throwing arm. These changes are often normal adaptations to throwing, but may also be a sign of restrictions developing in the arm. A loss of internal shoulder rotation is commonly called GIRD and currently defined as a loss of more than 20° of internal rotation on the throwing arm compared to the non-throwing arm. Research shows a significant loss in internal shoulder rotation after pitching, which can accumulate throughout a season if it’s not caught or left unaddressed. These changes can alter the biomechanics of the shoulder and increase the risk of injuries like labrum and rotator cuff tears.

External Rotation Range of Motion (ROM)

Baseball players often have greater external rotation range of motion on their throwing arm. In fact, research defines a pitcher having ER Deficit if their throwing shoulder doesn’t have at least 5 degrees more external rotation than their non-throwing arm. This is a normal and protective adaptation to throwing. Pitchers who have ER Deficit have a moderate increased risk of shoulder injury, and a significant increased risk of elbow and UCL injuries.

Flexion Range of Motion (ROM)

Shoulder flexion range of motion is an important factor when looking at injury risk. Baseball players should have the ability to bring the arms all the way overhead and should be symmetrical between the right and left sides. In fact pitchers with shoulder flexion deficit in their throwing arm greater than 5 degrees was determined to be the most significant categorical risk factor associated with increased elbow injuries. Your arm care needs to focus on shoulder mobility and range of motion at this time rather than starting a velo program.


Indicated through decreasing trend of strength & ROM.

Strength Fatigue Trends – Fatigue is the number one predictor of injury in baseball pitchers. Pitching while the arm is fatigued results in a 36x increase in the athlete’s risk of injury. By closely tracking your strength numbers through your assessment based arm care program, you will be able to pick up trends of decreasing strength if fatigue is present. It is not the right time to start a velo program when your arm is fatigued, and your strength values are trending down.

Shoulder ROM Trends – Acute changes in shoulder range of motion can be indicative of fatigue. Fatigue is the number one predictor of injury in baseball pitchers. Pitching while the arm is fatigued results in a 36x increase in the athlete’s risk of injury. By closely tracking your range of motion through your assessment based arm care program, you will be able to pick up trends of acute or progressive changes indicating fatigue or early injury is likely present. It is not the right time to start a velo program when your arm is fatigued.

Velocity development programs (Velo programs) are one of the most common training protocols being utilized by coaches across the country. These programs often utilize weighted ball programs in an attempt to train the athlete to maximize the utilization of elastic properties during a throw and increase throwing strength in their athletes.

But how do you know if an athlete is ready to participate in a velo program? How do we maximize the benefit of the velo program for each athlete? How do we reduce the injury risk during a velo program? The answer; utilize an evidence based pre-velo screening tool as a part of your assessment based arm care program.

Velocity Checklist

If you pass the Velocity Screen that is great. But just because your arm checks out, does not mean that you are ready or it is the right time to start a velocity program. Below is the Velocity Checklist that you need to pass prior to beginning a velocity program:


No arm pain while throwing

Hopefully this is an obvious point. You never want to throw through pain.


You are not in-season

During the season, your goal is to properly manage your workloads and recovery periods so that you feel fresh and strong. This is not the time to do a velocity program. Typically velocity programs are done in the off-season training period or the pre-season (60-80 days before the season begins).


Have been throwing consistently for at least 4 weeks

You need to build a base of throwing prior to engaging in any Velocity Program. Four weeks is the bare minimum. This base also known as chronic load will better prepare your soft tissue for the forces it will encounter during the velocity program.


Have taken time off if your workload was high last season

If you had a heavy throwing workload last season (80 or more innings) you need to take at least 2 months off from throwing. If this is you, focus on strength training during this down time.


Have a qualified coach designing & monitoring your program

You need the guidance of a coach who has a successful track record of conducting velocity programs with positive results. Meaning players are increasing velocity and staying healthy during and after these programs.


Your throwing mechanics are efficient

Throwing mechanics need to be analyzed on slow motion video and determined to be reasonably efficient by your coach.


Nutrition & Sleep are essential

Nutrition and Sleep are critical in promoting recovery. This is especially important when participating in a velocity program. Nutrition and sleep will not only have an impact on the health of your arm, but will also aid in your velocity development.


Understand & acknowledge that there are risks involved

Whenever you are pushing the limits of human performance there is going to be an inherent risk of injury…no matter how well you have prepared. But you are never going to reach your potential without taking some risks. Risk is a part of player development. The goal with this screen and checklist is to minimize those risks as much as possible.