How to Train the Lead Leg Block
What is a lead leg block?
The lead leg block is the entity in the delivery that redirects the force generated from the back leg, up the kinetic chain to the upper body. The “block” happens when the lead foot has contacted the ground and sends the lead knee from a flexed position to an extended position. To do this, the pelvis rotating into the lead hip requires lead leg to stabilize and extend to a certain degree. Ideally, a good lead leg block is timed up before and into ball release, not after.
Flexion to extension is a big contributor to throwing velocity, thus is why we will be discussing topics on how to identify, and how to prescribe based on what tools you have to fix the lead leg block.
Can a good lead leg block improve command? Yes. The ability to stop forward and rotational energy in the lead leg sends more energy to the trunk, shoulder, hand. The more efficient the lead leg, the increased ability for the thrower to maintain direction of the trunk and the hand to deliver the ball where it’s intended to be.
HOW TO KNOW IF A LEAD LEG BLOCK IS “GOOD”
Although not all lead leg blocks are created equal there are ways to tell if a block is great versus poor. We realize not everyone has a pitching lab to identify precisely what velocity your knee is moving to extension at, however looking at side video of the delivery and provide decent context to if you are timing up the lead leg block well or not.
For most hard throwers, the lead leg is stable and extending before ball release. Stability in the lead leg may be visually different when evaluating pitchers but the keys to look for are:
Foot/ankle stability — The foot lands and stays glued to the ground without changing direction or rolling over during the throw. (ex: lead foot lands then turns more to glove side as throw is being made (bad).
Lead knee stability — The foot lands and the lead knee stacks on top of the foot and stays there. Lacking lead knee stability would show the lead knee gets outside of the foot or continues moving forward as the throw is being made. A good lead knee would visually show the knee stop moving forward or east-west after lead foot hits the ground.
Lead hip stability — When the left foot and knee have began stabilizing after foot plant, the lead hip should also stop moving laterally and stack over the front foot during lead leg extension.
Below is an Ohtani video from side view to show the amount of force and quickness in his lead leg bracing. Does your lead leg do this? If it does, we ultimately want to reach max extension as fast as possible once our foot gets in the ground. The ability to send energy up the trunk into the arm requires a quality lead leg block prior to to ball release.
HOW TO KNOW A LEAD LEG IS BAD
On the opposite side of this discussion is how to determine if a lead leg block is bad. If your knee flexion stays the same at foot plant, or even continues to gain flexion (you sink even more into your leg as you move down the mound), this move typically does not correlate to strong velocity numbers, due to the negative correlation to redirect force at all, let alone with any sort of speed.
If you continue to go into flexion after foot plant, there is an opportunity for improvement. There are several factors that lead to a poor lead leg. The lowest hanging opportunities lie within prep work on the hips, mobility, single leg strength, rotational power, and ground force production.
Where does the energy go after the throw? Are the spinning off glove side? Typically, lead leg needs to improve if so.
Is the rear leg folding underneath? Typically, lead leg is falling more into flexion and needs improved.
Is the lead foot spinning while the throw is still being made? Typically, lead leg needs to improved by attacking foot and ankle stability.
Correlation of lead leg block to velocity
Here is where we dive into the math side of this discussion. Driveline Baseball has done many studies with their motion capture lab, both to prove and disprove how the lead leg block correlates to velocity.
When comparing lead leg reaction forces at the arm cocking stage, and arm acceleration stage, they found that the r^2 was strongly correlated with ball velocity at values from .45-.61. They had concluded that peak lead leg ground reaction force during the arm cocking phase was the best predictor of ball velocity.
This study was done for comparing the strongest correlator to velocity between the lead leg and drive leg, but that is a discussion for another day.
How we approach fixing issue
Now since we know the data is on our side, how do we go about fixing the issue here at PRP? From a mobility standpoint, we help you achieve those end ranges of motion by prescribing a movement assessment to find out why you move the way you move, and how we can make it better.
From there, our strength director will see how the athlete moves and produces force in the weight room (testing with Hawkin Dynamics). These numbers are an indicator of how much force the athlete may create on the mound. Then, we include patterning, single leg, and rotational work in the weight room.
The rest of our typical day plan is where all of the patterning of the delivery gets done, with the Core Velocity Belt, medicine balls, plyo ball drills, and actual throwing, which I will go into detail there. All drills being discussed will be linked at the end of this article.
How we prescribe with the Core Velocity Belt
For the lead leg, we have many different drills to offer that can be worked on with the Core Velocity Belt (CVB). One of the many great things that this tool has to offer, it can challenge and assist an athlete to get in virtually any position within the delivery.
Using another stimulus to challenge the athlete’s upper half (A PVC pipe, water bag, water ball), we will set up with the band on our lead hip, band behind, working away from the tension. Allowing the CVB pull the lead hip, creating an exaggerated amount of extension, over time with different variations of these drills will create a more natural lead leg block.
How we prescribe with Medicine Balls
The medicine ball is a tool that allows us again to pattern our lower half, without stressing the arm with throws, so we utilize them as often as we see fit.
A great way to challenge the lead leg block with med balls is actually by throwing up the mound instead of down the mound. An over the shoulder uphill slam with a medicine ball is one great drill we utilize in order to effectively pattern a better lead leg block.
How we prescribe with plyo drills
At this stage of the patterning workout is where we truly incorporate the upper half with the timing of the blocking that we have been working on in pre-throw skill work.
An example of one of our exercises that we utilize to get an easy feeling with arm timing and the lead leg would be a rocker throw. This drill focuses strictly on the lead leg plant. Making an emphasis on solely the lead leg creates a more controlled output when trying to pattern arm timing to the block.
Another variation for plyo throws in more constrained position in the split stance throw. This challenges lead leg stability and trunk rotation in prep work.
Higher level throws are often prescribed drop steps with med balls and plyo throws to improve the lead leg.
Summary
Ultimately, the lead leg is the stabilizer for the lower body to send energy to the upper body to rotate quickly. There is a strong correlation to ball velocity from lead leg flexion to extension velocity. It also improves strike throwing. The more force you can put in the ground, stabilize, and efficiently redirect the flow of energy from the ground up, likely will create a higher ball velocity.
The drills and methods outlined are only a few that we have to offer an athlete. There are several drills and weight room exercises that you can provide athletes to improve their lead leg patterns. There is no one singular way in how to train a certain movement pattern. At PRP, we challenge the athlete accordingly to receive the output we want.
Written by Max McKee
References
Boddy, K. (2022, August 30). Efficient front leg mechanics that lead to high velocity. Driveline Baseball. https://www.drivelinebaseball.com/2015/12/efficient-front-leg-mechanics-that-lead-to-high-velocity/