That’s right, I said it. Mostly everyone who completes some sort of training program often neglects this variable without even realizing it. Actually, they train this variable, but with little to know realization. That variable is the angle of the shin during athletic, and non-athletic activity. Shin angle is involved with every aspect of human movement, not just sprinting, throwing or swimming.

Whether you are a seasoned coach, or a parent looking to get their young athlete to the next level, you have probably tried to develop the ability of shin angle change. However, you probably didn’t use the best cues/ reasoning to get your athlete to do what you exactly wanted them to do. On top of that, if they couldn’t do it, you probably looked at another area of the body to solve the problem.

The angle of the shin dictates the direction of the athlete’s center of mass. During bipedal locomotion, the relationship between initial contact of the foot and the angle of the shin quite literally determines where the athlete is going, and where they will be going.

Let’s take linear sprinting for example, a 40yd dash. The goal of the 40 yd dash is for the athlete to cover 40 yds of distance in as little a time as possible. There are a a million variables that separate the fast athletes from the slow athlete, but one of the most important variables is how efficient the athlete is with each step they take. According to force plate data, elite sprinters can produce and handle up to 2500 N of force, but those are elite level athletes. How do those guys train to attain that ability? It’s technique.

Your body is constantly learning how to handle and optimize what you are telling it to do. There are certain optimal positions that your body needs to be in to even attempt to produce high levels of force at an extremely high rate of speed. Just like pitching, hitting, swimming, etc. If your technique is not optimal, it won’t matter how strong you are, you won’t be able to use your strength efficiently. The position of the shin sets up the rest of the body to attempt to complete the task required.

We can classify shin angle into 3 different angles: Negative, neutral, and positive angles. Negative shin angle means the shin (tibia) is behind the the ankle and foot (talocural joint). A neutral shin angle is where the shin is stacked vertically and in-line with the ankle. Finally, a positive shin angle means the shin is positioned in front of the ankle joint.

Each position will dictate the direction of force, therefore the direction of the body. For example, if an athlete is attempting to slow down, they will automatically try to find their heel by striking the ground with it. This heel strike forces a negative shin angle, and shoots forces produced by braking in a front to back direction. The result is that athlete slows down to an eventual stop.

A neutral shin angle is associated with a more vertical direction of force, like jumping. A stacked shin allows the athlete to put their force in a mostly top to bottom / bottom to top direction, resulting in actions like standing up, jumping, and squatting.

A positive shin angle is the key to horizontal locomotion to a certain point. This is especially true for the acceleration phase of sprinting. Having the shin in front of the ankle when contacting the ground means the force produced is directed in a back to front direction, and the athlete is in a position to move forward with less braking forces to compete with.

The athlete’s ability to understand these positions will dictate their understanding of sprint mechanics. This is especially true for those of us who think taking bigger strides automatically means a faster sprint time. Let’s break that statement down a little further.

Sure, a longer stride will create more time in the air, therefore less time having to deal with those annoying braking forces. However, the question of “how” those athletes attain longer strides is what’s key. Simply taking longer strides will more than often not solve the problem, and actually create a slower athlete. The reason being is that athletes who attempt to take longer strides typically cast their foot out in front of their shin and knee. Why is that less than optimal?….. The answer is above! They are now creating a shin angle more conducive to slowing down, rather than speeding up.

Sprinter with positive shin angle at mid-stance

What about running tall? Is this another cue you’ve used to help athlete’s sprinting ability? Sometimes this cue can work, but is often over-cued, and here’s why. A taller athlete is necessary during the late acceleration, and terminal velocity phases of sprinting. The athlete begins to rise out of their stance, and their force direction becomes more vertical. However, an athlete with a sprinting posture that is too tall, or even worse, too tall too early results in a shin angle that is too vertical! When athlete’s are sprinting “too tall” their shin is more neutral at initial contact, which is a position more optimal for a vertical force direction. In a race, where are we trying to go? Forward!

Now, don’t get me wrong, the direction you want to go in, at the velocity you are trying to attain is determined by the requirements of the moment. I am not saying a positive shin angle is the cure for male patterned baldness. The cure for optimized athletic performance starts with knowing how to get in and out of positions more efficiently than your competition. Because at some point an athlete will need to slow down, jump, change directions, etc. All I am saying is that you need to train the correct joint angles in movement to get the most out of your training.

I will close with this. Let’s get sprinting out of our head for 1 minute… don’t freak out, I’ll try not to. Look at other sports, and movements. When a swimmer leaves the blocks during a swim meet, what direction are they going? Forward. When a pitcher comes down the mound to deliver a pitch, what direction are they going? Forward. So, what shin angle would probably be best for optimal performance? A negative shin angle. Coaches must keep this fact when prescribing movement to their athlete, not only for the goals of enhanced performance, but injury prevention, and movement biasing as well.