Given the response to my last post on How to Run, I figured I needed to explain and expand on some of the concepts covered. To complement the reading heavy last post, this time around I've included a video and several pictures to help demonstrate some of the concepts discussed. I've also tried to address the problem of conceptualizing hip extension.
Before getting to the visual aids, I'd like to first give some practical cues for changing your running form. In what is becoming a reoccuring theme of this blog (and was mentioned in the comments by some astute readers), often what we see and what actually is happening are two different things. To help alleviate this confusion, I've listed some of the visual "problems" that are often seen in running, and then given their actual causes. While knowing the actual cause is great and all, it's useless without a way to fix it. To help you out, I've listed a number of possible "cues" to use to help correct the problems. Hopefully you find this information useful.
Finding the Cause:
Problem: Excessive Back Kick
Possible Causes: Too much forward lean, active pulling of foot to butt
Problem: Short/Flat stride
Possible Causes: Excessive extension of the entire leg, trying to toe off, too low of a takeoff angle, reaching out with lower leg to cover ground.
Problem: Very Little Hip Extension
Possible Causes: Trying to get quick with the feet and pulling them up early
Problem: Reaching out with the lower leg/heel striking
Possible Causes: Excessive/slow back kick, leaning backwards, delayed opposite arm swing because of the arm crossing or moving outwards, excessive shoulder rotation
Problem: Angle of swing leg too large or too small
Possible Causes: Hip extension either too great (for too small of an angle) or too small (for too large of an angle).
Problem: Reaching out with the lower leg
Cue: Put foot down behind you, as soon as the knee stops drop the foot to the ground
Problem: Hip Extension
Cue: Allow the hip to extend, Use the hip like a crank- initiate it let it go.
Problem: Flat/Short Stride
Cue: Think more vertical, have the horizon bounce slightly, don't push off the ground as long and leave the foot alone.
Problem: Excessively bouncy stride
Cue: Think more horizontal, watch horizon and limit the bounce.
Cue: Leave the lower leg alone. It’s just along for the ride. Be patient. Don’t try and get quick.
Problem: Dorsiflexion of the foot
Cue: Keep the ankle in a neutral position. Leave the ankle alone.
The biggest source of confusion in my last biomechanics article was on hip extension. This is my fault and a remnant of reading too many biomechanics papers. As with everything in biomechanics, there is a description of how it looks like and what it feels like. Describing what hip extension looks like is a piece of cake. It's best thought of as the moving of the whole upper thigh backwards in the running motion. It helps many to focus entirely on the hip joint, and think of the movement coming from there. This is clearly seen in the pictures below.
Describing what it feels like is a little more difficult. The point I was trying to make, but didn't come across quiet as clearly as it should have, is that the hip complex is where the power comes from. It's not from pushing off with your toes or with your calves. The cue should be to focus on the hip as your sort of speed control. As mentioned in my long post on the biomechanics, the hip acts like a crank. The faster you want to go the more powerful or quicker the hip extension needs to be. It's always present, it's just the degree of extension that controls the speed. Once you've initiated it, allow it to happen. It's not forcing the leg backwards, it's starting it and the letting it do it's work. This will take some experimenting around to get the right idea and correct feeling. Most runners start off with limiting the hip extension and then go to the opposite extreme in trying to force full extension on every stride no matter the pace. Eventually, you'll settle in as you become aware of just how much is really needed for each given speed. It's like when you first learn to drive and you're too hard on the breaks when stopping because you haven't fine tuned the process yet.
Pete Larson of the excellent blog runblogger.com sent me a great picture from the Boston Marathon that illustrates hip extension perfectly. Watch all of the elites in this picture and they all look remarkably similar with their extension leg. Note the degree of hip extension as well as the angle. As they say, pictures are worth a thousand words, so here you go:
Above is a series of video's I took at the park with a former runner I coached who now runs in college. Cody's a good example of someone who was a bad heel striker whose arms would also go crazy when he fatigued. He's come a long way and is a quick learner as you'll see in the video.
The reason I like this video so much is that you can see the progression of correction. On the first stride, you'll see a flat stride with a bit of a heel strike. Essentially, he's trying to cover ground by reaching out with his lower leg a little bit. Compared to the Cody of the past, this was a big improvement, but there's always something to work on. On the second stride, we tried to address the foot strike issue by getting him to focus only on putting his foot down sooner. Here you'll see that his feet come down underneath him and he lands midfoot. However, his stride is a bit shorter and a bit more choppy. That's a normal response when you get someone to put their foot down sooner.
On the last stride, our goal was to get him to lengthen his stride, but instead of doing it by reaching out with his lower leg, we did it by covering more ground in the air. The cue here was to focus on not only the power coming from hip extension, but also on projecting the body in the optimal direction with that push off. What that means is that we tried to increase the vertical component. Basically, Cody tried to introduce more bounce into the stride. If you go back and look at the 3rd stride, you'll see that Cody has a longer stride because of an improved push off/vertical component while still landing with his feet underneath him.
Hopefully in this video you can see the progression that Cody went through. The key was addressing one problem at a time and eventually putting it all together as a whole. First we got the foot strike fixed and then brought back in the stride length by pushing, not reaching.
The El Guerrouj Pictures:
I don't have a scanner, so you'll have to settle for some cell phone captured pictures of my El Guerrouj running shots. Although you can't make out everything, note the hip extension, body position, and overall relaxation of El G.