3 Focus Areas to Improve Biomechanics, Generate More Power, and Help You Run Faster

Biomechanics are a bit of a Pandora's box in the running community. Some say they're the ticket to getting faster and building endurance. Others think runners should just stick with what's comfortable and natural.

Regardless of which camp you fall into, there are a few fundamental aspects of running biomechanics that could influence running economy and performance, and certainly relate to injury prevention. Here are three areas to focus on if you're looking to improve your biomechanics, generate more power, and get faster.

1. Back Kick 

During the swing phase of the gait (when the foot is off the ground and moves from behind to in front of you), the foot acts like a pendulum. Your hip is the pivot point, and your leg and foot are "suspended" from the pivot point. When it comes to pendulums, there's one really important variable: the length between the pivot and whatever object is at the end of the pendulum. In this case, it's your foot. A shorter pendulum is faster (or in physics speak, oscillates with a smaller period). Applying this to running, from a biomechanical perspective, having a shorter leg pendulum would be most economical. How do you "shorten" the leg while running/walking? The back kick. In the picture below, you'll see how pronounced the back kick is in many elite runners (this one from the front group at this year's Twin Cities Marathon). The runner then actively brings the foot and leg forward through the gait by driving his knee. (One other thing to note: this is at mile 25!)

2. Knee Drive

As the right foot comes forward, the runner aggressively drives the knee upward and forward. This is where a lot of the runner's power comes from. But, he's only able to do this because of strong hip extensor muscles (muscles that are somewhat notorious for being weak in many runners). He engages his hip extensor muscles, and with a strong knee drive, also drives backwards with his left leg (the toe off part of the gait cycle). A pronounced knee drive also sets up the runner for an effective foot strike. See the next picture, particularly looking at the right leg/foot. The knee drive helps avoid excessive dorsiflexion of his foot. Dorsiflexion is when you point your toes upwards. Too much dorsiflexion usually sets a runner up for heal striking, while a more neutral position, such as in this picture, usually means a more mid-foot strike.

3. Foot Strike

Two big points on the foot strike. The first is that the runner strikes mostly at his mid-foot, which tends to generate less impact forces on the lower limb joints compared to heal striking. The second point is where the foot lands relative to the rest of the runner's body. It's almost directly under the runner's head and hips. In fact, you can basically draw a straight line from the top of the head, through the torso and hips, and finishing at the heal of the foot. Having this type of alignment, with the foot striking under the hips, enables the greatest amount of power to be generated.

By focusing on these three main factors over the past few years, I've seen some huge improvements in my own racing. For example, here's a side-by-side of what my "knee drive" looked like five years ago and what it is this year.

Take time to revisit the basics. Set a good foundation and the rest will follow.

A quick way to assess cycling aerodynamics

I finally had a light-bulb moment. I realized it can be pretty helpful having a brother who is a mechanical engineer. He's worked in performance car racing and understands aerodynamics!

There is huge cross-over with cycling and triathlon. How? In both scenarios, car racing (think Formula 1 race cars) and cycling, it's about maximizing power by, in-part, minimizing drag.

Now, if I wanted the gold standard in aerodynamics assessment I'd head to a wind tunnel. Unfortunately, that not exactly accessible to everyone. So, plan B.

My brother told me about this pretty cool app called 123D made by Autodesk (Autodesk also makes the computer program AutoCAD, used by many engineers, architects and land surveyors). Basically, you take a series of photos and the app constructs a 3-D model based on the photos. It's not exactly the gold standard, but constructing a 3-D model of yourself on a bike can provide some interesting insights into biomechanics and aerodynamics.

For me, one of the most helpful aspects was seeing what my torso is doing while in the aero position. The more "aero" you are - i.e. how close your back is to being parallel with the ground - the less wind resistance and drag. Result? You go faster!

Here's a series of still shots based on the model. The app allows you to zoom in and out, and rotate.

 

Give it a try and leave your thoughts in the comments.

Top Posts from 2013

Well, 2013 is officially in the books. It's been a great year - my first full year of blogging. I hope you have enjoyed reading my posts as much as I've enjoyed writing them.

Here are the most popular posts from the past year:

1. Minimalist running shoes: Are they really what we want them to be? 

2. What's wrong with the conventional wisdom on cholesterol and how it could actually be harming us

3. Making the best of it when things don't go your way: NJ State Triathlon race report

And, of course, if there are specific topics you'd like to hear more about, let me know. I'm always looking for new ideas and would love to hear from you.

Happy New Year and best wishes for a healthy and successful 2014.

My recipe to swim faster

Swimming never really came naturally to me. I grew up running around the soccer field, not cranking out laps at the local pool. Since the age of four all the way through my sophomore year of college, my goals were always around building soccer-specific skill, strength, and fitness.

That's not to say I didn't know how to swim growing up. I took swim lessons when I was young. I could hold my breath underwater for a pretty long time. I even spent a summer life-guarding at my neighborhood pool, which of course required me to pass a swim test.

My first few years of running were a natural extension of my years of soccer. It was what I knew best - running, endurance, and cardiovascular fitness.

So it shouldn't come as a surprise that transitioning to triathlon from running has taken a lot of work, particularly on the technical side. And of the three disciplines, none is more technical than swimming.

What I’ve found over the past few years after getting back into swimming is that, above all, technique matters! You can be the strongest guy or gal lining up at the swim start (or on the start blocks), but if you produce a ton of drag, you don’t stand a chance at swimming fast or economically.

Since taking up triathlon a few years ago, I've managed to cut my 100 meter time in the pool by about 45 seconds. Compared to last year, I improved my swim time at the Philly triathlon by 8 minutes - that's a little more than 30 seconds every 100 meters.

Here's my 3-F recipe that made it happen:

1. Frequency - I've talked about this before in previous posts, but for a novice swimmer it's all about developing a feel for the water. The solution isn't really rocket science - swim more often. I shortened my swim workouts, but increased their frequency to about five times per week. This approach is all about quality over quantity. It doesn't make much sense to develop endurance in the pool and do these massive sets if your stroke is inefficient. You're simply perpetuating bad habits. That leads me to my next point.

2. Form - This means drills, drills, and more drills. Improving technique helps efficiency, particularly to reduce drag (so you're expending less energy). This is a big part of swimming faster! For me, at least one workout per week is exclusively for drills, and I often incorporate drills into as many as three or four workouts each week. During the past winter I basically did a six week block where I more or less did nothing but drills in the pool. One of my favorites (which I continue to incorporate regularly into my sessions) is a drill called Unco - short for uncoordinated. The drill helps improve rhythm and timing of your stroke.

Here's a quick breakdown, but check out the fantastic site Swim Smooth for more detail. While using fins (unless you have a really good kick) perform a full stroke with one arm, breathe to the opposite side, and keep the opposite arm at your side -- essentially a one arm stroke. For example if you start with your right arm, you'd breathe to the left side. Do the drill for 25 meters or yards and then switch sides.

Photo credit: swimsmooth.com

3.  Flexibility -Strong ankles help stabilize during your foot strike while running. Unfortunately, this doesn't really help you in the pool. Strong ankles are often inflexible ankles; and inflexible ankles produce a lot of drag. Take a look at the picture (again from Swim Smooth). With inflexible ankles, your toes essentially point straight down towards the bottom of the pool, resulting in water being pushed in the wrong direction. This obviously slows you down.

Photo credit: swimsmooth.com

Two easy things I've done to increase flexibility in my ankles: 1) use fins, especially during kicking drills; and 2) ankle stretches. Stretching out the ankles is pretty easy. Here's a quick stretch I've tried to do on almost a daily basis.

My final point is about consistency. These are things I've incorporated over months and improvement will take some time. But invest the time and you'll be a better, more efficient swimmer.

Happy training.

Minimalist running shoes: Are they really what we want them to be?

Like many I began to think about so-called minimalist running after I read Christopher McDougall's Born to Run, which tells the story of the seemingly superhuman Tarahumara Indians and their ability to naturally run for miles (and essentially barefoot). Similar to what the Paleo diet has done in nutrition circles to reinvigorate an ancestral perspective with nutrition (to essentially think of nutrition or diet composition as something that should be strongly informed by what our ancestors ate thousands of years ago), McDougall's book sheds like on running from the perspective of human evolution.

Around the same time the book came out in 2011, discussions about barefoot running really started to take off and contributed to the serge of minimalist running shoes that came onto the market. (Many of the major running shoe brands now have at least one minimalist option.) A 2012 study in the Journal of Strength and Conditioning Research found that about 75% of more than 6,000 runners surveyed said they were "at least somewhat interested in running barefoot or in minimalist shoes."

So what's all the hype about? Why are so many people interested in minimalist running shoes?

More and more research is pointing to several benefits from barefoot running, such as fewer injuries or better performance. This study found runners in minimalist shoes or barefoot were 2-3 percent more economical while running on a treadmill than running in standard running shoes, likely due to improved "elastic energy storage and release in the lower extremity during minimal-shoe running." Comparing injury rates between runners wearing minimalist shoes (or running barefoot) and those wearing traditional shoes, other researchers found an injury rate 3.4 times higher in those wearing traditional shoes.

The basic argument for increased injuries when wearing traditional running shoes has everything to do with the biomechanical differences in foot strike. As I've discussed previously, when heel striking the equal and opposite force that is generated sends a shock to the ankle, knee and hips. Conversely, during a forefoot strike (which is more common with barefoot and minimalist runners), there is a much smaller impact force that's generated. For those interested in exploring this more, I highly recommend the above link on biomechanical differences in foot strikes. Looking back at the 2012 study of 6,000 runners I just mentioned, injury prevention was the most common reason for choosing to run barefoot or in minimalist shoes. More than a third of those running barefoot or in minimalist shoes said it was prevent future injury.

But, for some of the benefits, there are certainly some risks, particularly for those making the transition to minimalist/barefoot running after years or decades of running and walking in traditional shoes. In Lore of Running, Dr. Tim Noakes writes "only those with perfect biomechanical function were able to survive training; those with less than perfect function were soon injured and dropped the sport. Today, many runners who have very bad biomechanics are able to run prodigious distances only because of the very real improvement in the design of running shoes. In the past, they would simply have had to stop running because of recurring injury."

In fact, there has been research to suggest that many of the benefits of barefoot running are in those who have consistently trained their feet and surrounding musculature to adapt. The main take-away - if you're interested in running barefoot or in minimalist shoes, it's going to take time. More on this later.

I'm personally about a year into the process of transitioning to more minimalist running (for all the reasons I've already discussed).

I went from running in these about 18 months ago...

To these about 6-12 months ago...

And began running in these about 4 months ago...

But one of the interesting questions - and one that isn't addressed often in the literature - is if minimalist running shoes actually does a good job of simulating barefoot running from a biomechanical perspective. There's plenty of evidence showing a clear difference with traditional running shoes, but studies often lump minimalist running shoes into the same category as barefoot running. The big question is....is this a good assumption?

Well, taking a look at a study from earlier this year published in the British Journal of Sports Medicine suggests it might not be. Researchers looked at the 3-D kinematics at the hip (top panels), knee (middle panels) and ankle (bottoms panels) joints for the stance phase of the gait cycle (this is when the foot is in contact with the ground) of four different shoe types: barefoot, minimalist, racing flat, and traditional running shoes.

Here is a breakdown of what they found...

It's slightly difficult to interpret because the graph is a little small, but here are two main points.

First, you'll notice that much of the kinematic variation is at the ankle and knee, and much less so at the hip. Barefoot runners showed a reduction in peak power generation at the knee, but an increase at the ankle compared to all other running types. You basically have a shift in the joint being stressed when barefoot running from the knee to ankle. This is, in my opinion, one of the important reasons for a gradual transition if you're thinking about dumping those regular running shoes and hitting the pavement barefoot.

As I mentioned before, it takes time to build the necessary foot and ankle strength to accommodate barefoot running (or minimalist shoes in some cases). By making the transition too quickly you run risk of injury. This is even the case when transitioning from traditional running shoes to more minimalist shoes. Start by spending more time walking around the house barefoot, or introduce one workout a week in more minimalist shoes. Over time and with increased strength in the foot, ankle, and calf, you'll be able to slowly build volume.

Second, kinematic analysis showed that the joints examined tended to act more alike in minimalist, racing flats, and regular shoes, compared with barefoot running, which had it's own unique kinematic profile. So, what does that mean? Well, essentially, there isn't too much of a difference between regular running shoes and minimalist shoes from a kinematic perspective, despite all the marketing claims. (One word of caution: this study looked only at one particular type of minimalist shoes - the Nike Frees - and didn't necessary look at all commercially available minimalist shoes, such as those from New Balance, Saucony or Brooks.)

So, if the hope is to mimic barefoot running by buying a pair of minimalist shoes, you might just want to slowly ease into the real thing. As much as we'd like minimalist running shoes to give us the same experience as running barefoot; well, that simply might not be the case. And if you're hoping to improve your biomechanics, you might get a higher bang for your buck by focusing on running technique and drills instead of dropping a hundred bucks on a new pair of kicks. Recalling the mantra of running coach James Dunne - form before footwear!

How I ran less to run better: 5 things I did to qualify for Boston

This post is the final part of a series of posts on endurance sports and heart health.

Training is both a science and an art form. There are, of course, scientifically supported ways to optimize performance - training structure, duration, intensity, biomechanics, etc. But, as much as I've learned from books, podcasts, and other coaches, I've learned even more from simple experimentation. That's where the science starts to blend with the art form.

To me, training has always been about testing myself and finding new ways to achieve even greater performance. By developing an intimate understanding about my physiology - how my body responds best; when it's tired; when to up the intensity; and what type of fuel is best - I've been able to make huge improvements and go beyond what I originally thought were my physical limits.

In my previous post I talked about how nervous I was leading into the 2012 Philadelphia Marathon. It wasn't the distance, but my preparation. My training was dramatically different than what I was doing just a few years ago. I basically had two fundamental goals with my 2012 training: 1) maximize performance (particularly speed); but at the same time 2) optimize overall health and well-being. The first part is fairly obvious, but the second is a much greater recognition and appreciation for many of the negative health effects resulting from chronic endurance exercise. I wrote about this in greater depth here and here.

5 things I changed to improve my training and qualify for Boston:

1. Biomechanics

Running is all about efficiency and economy. One of the greatest causes of stride inefficiency is over-striding, or when your foot lands in front of your center of gravity. Think physics - force is always equal and opposite. When you over-stride, the force generated comes back up into your heel, your knees, and your hips, slowing you down, but also increasing the risk of injury. The biggest warning sign is a significant heal foot strike. (I'll admit, I followed the classic "heal-toe" advise for several years and even wound up with a slight hamstring injury from overstriding.) So, the goal was to make sure my foot always struck under my hips.

To get there I changed three things: 1) I started actively picking up my feet (as opposed to pushing off the ground); 2) I increased my cadence; and 3) I ditched my old clunky shoes with tons of cushion for a more minimalist shoe, which forced me to address some of my faulty biomechanics I was getting away with, and assumed a more natural stride and foot strike.

2. Training volume

Less became more and quality replaced quantity. There's a growing body of research that points to the benefits of high intensity interval training, particularly when comparing metabolic and biochemical adaption with traditional endurance training. In addition, interval-based training is one way to get around some of the longer-term negative health effects, particularly with the heart (which I reference above), from chronic endurance training. I made intervals the foundation for my training approach.

My weeks usually included three days of solid run sessions, with a fourth optional recovery day. One week always included a shorter interval-based workout (never more than 40 minutes), a shorter tempo or fartlek run, and a longer interval-based session. The focus was always on intensity during the workout, and recovery afterwards. Long workouts were never more than 2 hours or longer than 16-17 miles total, and total weekly mileage was never more than 30ish miles. This is in stark contrast to the 40+ miles a week of old.

Training philosophy was the hardest thing to change, mostly because it was totally counter to everything I previously thought. But, I trusted it, and it worked. 

3. Training style

Becoming a better runner isn't necessarily always about running more. I think my many of my improvements over the past 18 months have a lot to do with the non-running parts of my training. Triathlon training has been key. First, cycling forced me to improve the strength, power, and endurance in my legs, particularly my quads and glutes, offering a great carry-over effect with my running. Also, incorporating sessions that improved my cycling cadence had a similar effect that "taught" my legs to turn-over faster, which was essential for the tweeks I made in my biomechanics.

Second, swimming had less of a carry-over effect, but my interval-based training in the pool improved my cardio-pulmonary capacity in ways that complemented my running. Not to mention, including kicking drills on a regular basis were great for both strength and recovery.

Lastly, I religiously incorporated at least one (and often two) days of strength training and/or plymometric work to increase power and develop functional strength. This has been vital for injury prevention, longevity, and speed.

4. Overall Nutrition

Goodbye processed food, wheat and many carbohydrates. Hello real, whole foods.

I was never overweight, but my diet wasn't necessarily "clean." In other words, because I was playing sports and exercised (and probably from a genetically faster metabolism), I found I was able to get away with not always paying close attention to what I ate. Things like pasta, bread, chips, pancakes, cookies, etc, were pretty routine. I even thought I had to eat this way because my body was burning so many calories and carbohydrates.

Now, vegetables, fat, and protein form the foundation of my diet, with carbohydrates, such as oats, lentils and quinoa cycled into my training based on when my hardest workouts are. By keeping carbohydrates in check, and being strategic with intake, my body adapted to burn more fat as the primary fuel source. Not to mention, I'm able to maintain a much more constant blood glucose level, rather than the peaks and valleys that go along with massive insulin spikes. One of the simplest (though hardest at first) things I found was to eliminate wheat, which is one of the biggest culprits with blood glucose fluctuations. Not only are there a variety of ways wheat contributes to chronic disease (a must read on the subject is "Wheat Belly" by Dr. William Davis), I also found eliminating wheat (and all refined carbohydrates and sugars) helps me 1) maintain more constant energy levels; 2) allows for better recovery post workouts (particularly long/intense workouts), and 3) because stored carbohydrates carry more than double their mass in water, drop about 15-20 pounds of what I call "junk weight."

One of the huge advantages of dropping this "junk weight" - where I went from weighing about 20lbs less during the 2012 Philly Marathon compared to 2007 - was it's effect on running economy. In what is probably one of the most comprehensive book on running, Dr. Tim Noakes writes in "The Lore of Running" that research has shown that "the addition up to 4kg to the torso increased the oxygen cost of running by...2.5%." Further, that "the addition of 0.5kg to each thigh or to each foot increased the oxygen cost of running by 3.5% and 7.2% respectively." In short, a lighter runner can more easily be a more efficient runner.

5. Race-Day Nutrition

I said goodbye to sports drinks and gels, both in training and on race day. Instead, I used UCAN Superstarch for workouts over 90 minutes and on race day. UCAN Superstarch is a slow-releasing, high molecular-weight carbohydrate that results in a much smaller insulin spike compared to simple sugar-based products like sports drinks and gels.

Why is this important?

Two points. First, the body has a limited supply of glycogen, or storage sugar, which, if used exclusively, is exhausted over the course of a couple hours (faster at higher intensities). This is the basic reason behind consuming sugar in the form of sports drinks or gels during a marathon or triathlon. However, this leads me to the second point. When suger is ingested, huge insulin spikes follow, resulting in the body preferentially burning glucose and essentially shutting down its ability to burn fat. When blood glucose levels are maintained in a more moderate range, the body is better able to tap into its massive fat stores. And for those more fat adapted through their everyday diet, like myself, this has huge performance and endurance benefits.

There ya have it. Five big changes I made to improve my running performance. These weren't all done overnight, and many were things that took a lot of patience. But in the end, it was about trusting the approach, and trusting myself.

Let me know your thoughts.