8 Reasons Athletes Injure Their Hip Flexors

Last Updated on January 28, 2015

This article is guest blogged by Travis Hansen, author of The Speed Encyclopedia.

He also wrote Why Acceleration is More Important than Top Speed in Most Sports and Building Your Horsepower – The Power Development Model Part 1 and Part 2, which are full excerpts from his book.

To read all his articles on this blog, click here.

The hip flexor region is undoubtedly one of the most talked about areas of the human body when it comes to performance training. Most of us are familiar with a dozen or so different muscles that originate at and around the pelvis and lumbar spine, and then insert down past the knee to various locations on the tibia and fibula. This series of musculature is essential to walking, running, sprinting, jumping, decelerating, and everything else athletic. However, in the majority of cases, they are simply deemed as a “bad guy” which is always overactive, tight, and a primary site of injury or potential injury that we need to address to stay healthy and perform better. Based on how we function and the location of these muscles and how they function, this can definitely be the case; however, they aren’t always bad.

In this article, I’m going to talk about a few not so common mechanisms of hip flexor injury in athletes and how to fix them:

#1-Anterior hip mobility/flexibility deficits

#2-Poor Dorsiflexion strength

#3-Low Heel Recovery

#4-Weak Posterior chain Development

#5-Gait patterns

#6-Global posture

#7-Being athletic!

#8-Weak quads or hip flexors

Ok, now very little time needs to be dedicated to this first one I imagine. Muscles such as the Adductors, Rectus Femoris, and the Psoas group are major culprits when it comes to “Reciprocal Inhibition” of the power muscles of our hip. The Thomas Test, Half Kneeling rear foot elevated stretch, heel to butt stretch, and heel to butt runs are some of the many drills you can implement into your training programs right now to rid of any unwanted adhesions, scar tissue, tightness and soreness that may be limiting your ability to really extend your hip and drive more power into the ground in athletic based movements. This is just your classic Anterior Pelvic Tilt or Lower Crossed Syndrome.

The next cause of hip flexor strain is indirectly caused by poor mechanics specifically at the ankle joint of the swing leg during a sprint cycle pattern. More specifically, if the foot of the swing leg does not dorsiflex enough then the toes will be left pointing down towards the ground. Unfortunately, if this happens then the calves do not reset into a stretched position, and you will lose speed and power at the foot when your foot lands back down on the ground again. What is maybe even more important is that this unwanted action makes our entire leg a bit longer which requires the hip flexors to work harder than they already have to when sprinting. Multiply this across several foot contacts and leg swings and you can see how the stress can compound and further predispose this area to injury.

READ Armin Hary and the IAAF Reaction Time Rule (Part 1)

Heel recovery was a technique that I was first introduced to by Coach Latif Thomas. It’s the path the foot takes as it pushes off the ground and swings back through in front of us as we land. Unless we are coming out of 3 or 4 point stance and accelerating then our foot should rise and pin underneath our glute, step through the knee, and then land in front of us. Often though, athletes won’t set their foot into their rear, which causes the foot inevitably to swing low and places an excessive amount of stress on the hip flexors just like with the weak dorsiflexion scenario I just discussed.

Just like with the flexibility deficiencies of the hip flexors that I just discussed, most everyone now seems to appreciate how fundamental the glutes and proximal hamstrings are in preventing our pelvis from tipping forward and keeping the various hip flexors in overdrive.

What is not always appreciated though is the “specific” strength the hamstrings need to be able to exhibit to prevent overstriding and domination of the Rectus Femoris muscle just before we land during sprinting. First, what actions comprise the act of overstriding in sprinting? It’s concurrent knee extension and hip flexion. What actions does the Rectus Femoris perform in human movement? Knee extension and hip flexion. This muscle is largely responsible for causing an athlete to reach their leg too far out in front of their center of mass during sprinting. This position not only increases energy loss and ground contact time, but it makes us slower and tells our central nervous system to keep sending contraction signals to the overused RF, when the brain should be cuing local nerves at the hamstring to keep the knee bent, so we don’t overstride.

I’ve been observing the repetitive motions that occur during gait recently. Most know that flexed positions which are common to sitting, soccer, lacrosse, football, rugby, and other functions can create various hip flexor issues, but I don’t think gait or just general walking is talked about much for athletes. When you analyze the nature of the hip while walking, you will notice that we sub-consciously never fully extend the hip or arrive in a hip hyperextended position. The downfall to this is that we tend to stay fixated in a knee bent/hip flexed position.

Bret Contreras, who is one of my favorite speed researchers, shared some information in a recent article that has some application here I think. He cited that hip extension and knee flexion increases more than any other joint motion as velocity increases during sprinting from mid to maximum levels of speed. Meaning that the faster we move, the more our glutes and hams get turned on, and the more our hip flexors will shut off. Unfortunately, I’m not sure if enough athletes are participating in “true” maximum effort speed training to make sure they exit anterior dominant gait patterns and the other negative adaptations that could occur with too much of one posture or one movement (i.e. adaptive shortening). Combine that with everything else, and sprinting becomes absolutely essential in my mind. Gait analysis and Bret’s research supports the need for athletes everywhere to make sure they are getting some dedicated time to speed work in their programs.

READ 8 Key Tips To A Better Vertical Jump (Part 3)

Global posture refers to structural imbalances that are present away from the local area, which in this case is the hips. Tight calves creating a subtle weight shift back, a rounded posture at the shoulders, and a forward head are all players in the posture game and can cause our hip flexors to become or remain tight. Make sure to look throughout the entire kinetic chain for any imbalance or weight shift that could be potentially wreaking havoc on the area you are trying to clean up and optimize.

You probably would have ignored the notion that being in the right athletic position can break down your hip flexors over time. The athletic position does involve a component of hip flexion. Moreover, the dominance of weight in the front of our foot (Forefoot Dominance) may subsequently increase hip flexion to help counterbalance what is happening at the foot at that moment. It also helps to set the glutes in a more lengthened and effective position to contract and maximize force output. (Length-Tension Relationship). You don’t see sprinters or any fast athlete with a rounded lower back when they run do you? Yes, me either. Their butt is out; hips are loaded, and their center of mass is placed over the front of their foot which makes them more reactive, among other things.

Now does this mean we should abandon the athletic position or revise it? No way. This alignment makes athletes more efficient and effective in the movement. The only modification that should be made is to make sure they get out of it, or that we counteract it with ankle mobility and hip extension drills. Too much of anything can be bad when it comes to training!

The last one is going to initially seem probably a bit paradoxical after what I’ve just said and according to what you may have heard about quad and hip flexor overuse theory, but it’s true. Anecdotal evidence, as well as research, has supported quad strength, mainly through the concentric phase as an indicator of acceleration and speed success. 3 4 Biomechanically, there is very little momentum present at the start and during low speeds, so it’s just a matter of how much total force and strength an athlete can summon throughout their entire body into the ground to get their body moving faster.

Knee angles are greater during acceleration, and that helps explain the quads value at that phase. Moreover, a recent study showed the importance of the collective hip flexors in being able to start and accelerate during a linear sprint. 5 With all that being said, it would make sense to me that we may be slow due in part to weak output from the quads and hip flexors, and this weakness may be a contributor to injury that occurs to these muscles, especially at short distances?

READ Building Your Horsepower – The Power Development Model

In the athletes that I’ve worked with in the past who hurt their quad, hip flexors, or groin all had pretty poor lower body strength to bodyweight ratio’s, and failed a standing above 90-degree psoas test. Now I’m not saying it was the cause of the strain, but these deficiencies may have contributed. Furthermore, not every athlete is lordotic and carries good tone at their hip flexors and quads, so they may need to supplement some single leg work and squats into their programs. Finally, Bret also discussed the critical importance the psoas has on swinging the thigh upward and research has identified sprinters are generally bigger and more muscular, but they are also bigger around the hip flexor region as well.

SCIENTIFIC REFERENCES:

#1-Clark, M. A Scientific Approach to Understanding Kinetic Chain Dysfunction: 2001.

#2-Sprinting and Glutes

#3- Young, W, Benton D, Duthie G, and Pryor J. Resistance training for short sprints and maximum-speed sprints. National Strength and Conditioning Association 23: 7?13, 2001.

#4-Bret C, Rahmani A, Dufour AB, Messonnier L, Lacour JR. Leg strength and stiffness as ability factors in 100m sprint running. Journal of Sports Medicine and Physical Fitness 42:274?281, 2001.

#5-Bushnell T, and Hunter I. A biomechanical analysis of sprinters versus distance runners at equal and maximal speeds. Sports Biomechanics 6: 261-268, 2007.

#6-Hoshikawa Y, Muramatsu M, Lida T, Uchiyama A, Nakajima Y, Kanehisa H, and Fukunaga T. Influence of the psoas major and thigh muscularity on 100m times in junior sprinters. Medicine and Science in Sports and Exercise 38: 2138?2143, 2006.

About the Author

Travis Hansen was the Head Strength and Conditioning Coach for the Reno Bighorns of the NBADL for their 2010 season, and he is currently the Director of The Reno Speed School inside the South Reno Athletic Club. He is the author of The Speed Encyclopedia.