Tuesday, July 19, 2011

Running cadence

The other day I realized that even though it has the title "Rebuilt Runner", my blog has precious little on it about running.  I tend to write about what is on my mind, and because I've been doing a lot of other types of exercise lately, that's what I've been writing about.  But that's all gonna change today!

When I started running again a few months ago, I decided to completely retool my form.  I had learned a lot about running mechanics during my many months of injury, and I knew that now was as good a time as ever to start from scratch.  I kept reading about the importance of striking on the midfoot, but as hard as I tried I could not figure out how to actually do it.  I could either land on my heel as I had been doing for years, or I could run entirely on the balls of my fight.

After a couple of weeks of awkward experimentation, I decided to try working on something else-cadence.  Cadence is how often you take a step, the rhythm of your running.  Everything I had read suggested that 180 steps per minute was the best, so I got on on the track and tried this new, faster pace.  Amazingly, as soon as I made that change, I naturally started landing on the midfoot!

Everything in running is connected, so when you improve one element, it will improve others.  Taking that many steps felt clumsy at first, because I been taking long, loping strides for so long.  But when you take many small steps, you feel lighter, smoother.  It's like a ballerina up on pointe gliding across the stage; she takes so many small steps that it looks like one fluid movement.  This feeling is what you are going for.

This cadence was so different from how I used to run, that it took a long time to get the new rhythm etched into my muscle memory.  I even went so far as to get a metronome app for my iPhone and run with the program clicking away three times a second in my ear.  If you don't have a smartphone, you can just look at the seconds ticking away on your watch, and count "DA-da-da-DA-da-da-DA-da-da..." for several seconds before each run.

The difference it makes is tremendous.  With a slower cadence, you go up really high and come crashing down hard with each step.  With a fast cadence, you rise and fall less, and the force of the landing gets spread out over more steps.  This makes running easier on your body and can help to avoid injury.  You also run faster...too fast, sometimes.  To run slowly with a high cadence, you need to have a shorter stride, and learning to vary your stride length with your pace is a skill that takes time to develop.

180 bpm isn't a hard and fast rule; like everything in running, it depends to a degree on your own body shape.  Some may find slightly faster feels more comfortable, while others might find that slightly slower works better.  But the variability should be small.  I saw a slow motion breakdown of the top five finishers in the latest Boston Marathon, and everyone was within about 5 bpm of 180.  So if it works for them, that's good enough for me.

Friday, July 15, 2011

Born to Run

This book got a lot of attention a few years back, mainly for having brought the minimalist running movement into the mainstream.  I got the book because I heard it had some good info about running form, but I found it had so much more than that.

It is the true story of Christopher McDougall's odyssey into the world of an ancient Mexican people called the Tarahumara who live in a remote canyon, speak their own distinct language and have a culture built around running.  In the Tarahumara tongue, their name for themselves actually means "the running people."  They will go on 120 mile treks through blazing hot canyons while covering their feet with only sandals.  And these aren't just the few star athletes; most Tarahumara people can do this.

What happened to McDougall was an incredible personal journey, and he tells it with the prowess of the best novelists.  The book contains stories within stories, and the many eccentric people he meets along the way are painted with vivid detail.  For example, the story of Ann Trason battling two Tarahumara men in a grueling 100-mile race through the mountains of Colorado is as thrilling a sports story as I have ever experienced.  It's quite possibly the most exciting book I've ever read, and what's amazing is that it is absolutely true.  Maybe that's why it is so exciting, because you know these are real people having amazing experiences in a bizarre and inspiring sport.

Every runner should read this book, but I think everyone else should read it too, because it is just a great story.

Thursday, July 14, 2011

Overcoming oxygen debt in swimming

I recently got back into swimming, and I was reminded of how hard it is at first.  I was pretty fit, but I couldn't go for more than five minutes without needing a break.  The problem was I wasn't getting enough air and felt like I was drowning.

This feeling is called going into oxygen debt, which means you are using more air than you are taking in.  It is incredibly uncomfortable, and in my case causes a sense of panic.  In order to keep swimming, I needed to find a way to either take in more air, use less air, or both.

Breathing while swimming is different then breathing while running or cycling (or really any other sport) because you can only breathe at discrete times.  For the freestyle stroke, you can breathe at most every time an arm pulls through the water.  So if you are already breathing that frequently, you can't breathe any faster.  Another obstacle is speed; some speeds are more efficient than others, so swimming more slowly might actually require MORE oxygen then swimming quickly.  I'm very dense, so the slower I swim the futher my legs sink into the water.  This shape is much less hydrodynamic, which makes swimming harder.

So what can you do?  The key for me is taking longer, deeper breaths, and focusing on my form.  First, lets talk about breath.  You can only breathe in when your head is turned all the way to one side, but you can breathe out any time.  So breathe out slowly while you are turning your head, then once you get your face our of the water you can use that entire time for breathing in.  Try to hold your head above water as long as your stroke will allow, and breathe in deeply and slowly.

Next, there is form.  Of all of the endurance sports, swimming is the one where form matters the most.  This is because the shape you make determines how easily you can move through the water.  If your form starts to slacken, you will change your drag coefficient, which will make swimming harder.  So actively thinking about your form will help you to stay in that nice hydrodynamic shape.  Also, keep the tempo up; slowing down may seem easier, but because your breathing rate is tied to your cadence, you wont actually be improving your air/work ratio.

The next time I swam, I found that as I worked on these two things, then I was able to swim farther.  Oxygen debt still eventually overtook me, but that is because my swimming fitness is down.  As my cardiovascular system improves, I will be able to take in more oxygen with each breath.  And as my swimming muscles get stronger, they will be able to do their work more efficiently, requiring less oxygen.  The key is to gradually swim farther and farther each time, and eventually supply will catch up with demand and swimming will get easy.