QUAD MUSCLES IN RUNNING

Quadriceps femoris muscle, or simply - quads, is a large fleshy muscle group covering the front and sides of the thigh. It has four parts: rectus femoris, vastus lateralis, vastus medialis, and vastus intermedius. They originate at the ilium (upper part of the pelvis, or hipbone) and femur (thighbone), come together in a tendon surrounding the patella (kneecap), and insert at (are attached to) the tibia (shinbone). (Encyclopædia Britannica)

Quadriceps group is among the largest muscles of the human body and is essential to many movements routinely performed on daily basis. We do what we do and do not give the work of our quads a single thought, and they perform smoothly and without a glitch.

We incur injuries when we interfere with the work of our muscles or perform incorrect movement. What we need to know is how to do something properly and our body will distribute the workload and the leading roles. The roles of course change as necessary, the same muscle group performs several different functions according to the 'action' happening. (Functional System, P.Anokhin)

In running, quads play an essential role by providing stability during the support phase. That's it. Immediately after the midstance (support phase), the quad muscles cease any electrical activity. In plain English, your quads stop working right after you start falling or leaning forward.

The workload of roughly 75% goes to hamstrings, the remaining 25% consists of the work of all other muscles combined, quads included.

As you see, there is not much to this topic, it is not as complicated as it is usually made out to be. If the extensor paradox was properly understood and not ignored in 1990, lots of runners could have easily avoided quadriceps and hamstring injuries. It is when the work of hamstrings and quadriceps clashes that they get hurt.

Here is one more misunderstood thing. There is a popular quads stretch which is actually a flexibility exercise for the knee. It is always recommended as part of a warm up which is a huge mistake. It should only be done once you're already warmed up. There is a potential to harm your quad muscles if this flexibility exercise is imposed onto an unsuspecting and unprepared thigh.

To round it up, if your quads are misused - they hurt and you don't run good or fast. However if you strengthen them and let them do their simple work - you'll benefit greatly. Add to that good running technique and you will run better and faster and avoid quadriceps' injuries.

Article by Dr. Nicholas Romanov
Composed by L. Romanov