Monday, June 22, 2009

In Praise of the Little Muscles

The more I learn about how animal bodies achieve motion, the more impressed I am by the mechanical engineering that has been achieved by Mother Nature through some millions of years of evolution. Prosthetic limbs and robot arms that have been built to date by humans can’t come close to duplicating Nature’s exquisite designs. For example, I recently saw the latest personal robotics research coming out of Willow Garage. They’re doing interesting work, though as someone who has watched robotics research from the sidelines for 30 years or so, it’s clear that real progress is still slow, and we’re still a long way from giving Nature any serious competition, either from a physical performance point of view or from a computational intelligence point of view.

As someone who has never really studied anatomy in any detail, I also never fully appreciated just how many muscles are engaged in simple motions, what it takes to use and control them properly, and just how important some of those little muscles that we tend to ignore can be. There’s nothing like an injury to a minor muscle to teach you what their importance and function are.

My first experience with a “minor” muscle injury was some years ago. I tore my right piriformis muscle doing a lunge while fencing. (Look up all the muscles mentioned here at Get Body Smart.)

The Piriformis is a little muscle under the Gluteus Maximus that is used for leg rotation at the hip. I knew I’d done something bad at the time, but I didn’t have much in the way of acute pain and mostly just ignored the injury. Some months later I was experiencing chronic but vague hip discomfort and a sense of looseness in the joint. A good physical therapist was able to diagnose the problem from my assortment of vague symptoms, and having diagnosed the problem (the muscle at that point was seriously knotted), it was a straightforward, if slow, process to undo the damage and get the muscle back to normal function.

Apparently, there aren’t a lot of nerves in these small muscles compared to the major skeletal power muscles, and one can’t necessarily feel the damage unless you find the muscle and start to really knead it—something that can be hard to do for a muscle that is hidden behind something much bigger. It took a year or so of regular rubbing (the corner of a countertop or table
worked great!) before the muscle stopped acting up from time to time.

I had a similar experience with the upper part of my right Soleus muscle. In that case the injured muscle was hidden underneath the big calf muscle (the Gastrocnemius). The Soleus contributes to flexing the foot, and thus is commonly stressed by running.

Again, I was experiencing vague calf pain while not having any obvious pain in the big muscles. Once identified, Soleus muscle damage can be easily massaged by lying on one’s back and resting the lower leg on the opposite bent knee. Move the lower leg back and forth over the knee with the Gastrocnemius fully relaxed, and you should easily be able to find any tender or knotted
areas. Even though I don’t have any particular damage problems with this muscle now, I still find it a useful post-run massage to do—the Soleus muscles often take a beating on a long hard run. Also, while I generally subscribe to the theory that warming up slowly is far more important than stretching (which can be downright counter productive, promoting rather than preventing injury), I do find it useful to stretch the Soleus muscles by flexing the foot up with the leg straight (which also stretches the Achilles tendon and attached structures).

My most recent experience was the most dramatic yet. It introduced me to yet another lesser-known muscle that I had been completely unaware of and left me unable to run for several weeks! After running many hundreds of trail miles over rough terrain with little more than routine sore muscles and the occasional minor bumps and scrapes, I managed to injure myself on the track! I was well warmed up and had just run a 7-minute mile (about as fast as I can go for that distance). After a lap or two of cooling down, I decided to sprint for 100 m or so. Mistake! I almost never really sprint, and I don’t really have well-developed sprinting muscles and technique. Again, I knew I’d hurt something, but I wasn’t quite sure what. A couple of days later, about seven miles into a twelve-mile trail run, I landed slightly wrong on the injured leg going downhill, and felt a sharp pain in my knee. After the acute pain subsided, I was suddenly unable to run at all, though I could still walk with minimal limping and was able to walk the rest of the way.

It turns out that the damaged muscle this time was the Popliteus. (And no, there was not any ligament or cartilage damage at this point.) This seeming unimportant muscle is located immediately behind the knee running diagonally across the leg from the outside (at the top) underneath the top of the Grastocnemius muscle. It’s pretty hard to find even when acutely injured, but it can be massaged (carefully! there are other sensitive structures nearby) if the Gastrocnemius is fully relaxed. The Popliteus muscle serves at least three important functions. First, though it has very little power being very small, it is the first muscle that fires when you bend your knee from a fully-extended position. Second, it helps hold the knee joint together. Third, it helps prevent you from “hyperextending” your knee (going past the normal maximum extension—straight leg). Lacking a normally functioning Popliteus muscle is surprising debilitating! The knee joint just doesn’t work right. Most joint motions involve multiple muscles that are fired in an exquisitely timed sequence to achieve the full action. The Popliteus fires first
for knee bending, and without it, your timing falls apart. The joint looseness and potential for hyperextension leave the joint cartilage vulnerable. My attempts to continue at least light running caused acute pain to develop at the medial meniscus, the main piece of cartilage padding the knee joint on the inside. The weak Popliteus muscle allowed excessive pinching of the
cartilage, especially on impact. In effect, the Popliteus muscle also plays a key role in the sequence of muscle firing that provides shock absorption as you land on your foot when running. This particular problem is peculiar to running; walking and bicycling were possible with little or no pain. (With most knee injuries, bicycling is painful, since it tends to put significant stress on the knee.) Of course, as with any injury, any limping or other change of gait, whether conscious or not, tends to stress other muscles that are compensating for the injured muscle in unusual ways. In this case, I got quite sore in the adductors in the opposite leg!

The good news is that, while recovery has been slow and I was unable to run much at all for a few weeks, no lasting damage occurred. I walked and bicycled more, and eased back into running with shorter, slower distances, being particularly cautious on the downhills. Ibuprofen and a simple knee brace also helped enable a little more activity sooner, and I managed not to lose too much conditioning. I also followed the recommendation to take a Glucosamine/Chondroitin supplement.

I also took advantage of the slower shorter distances to start to switch over to more “toe” running (landing on the ball of the foot rather than the heel). This reduced the impact on the medial meniscus, again allowing me to run more sooner, though it has required developing a slightly different set of running muscles. (You use parts of your Gastrocnemius muscles more for shock absorption when landing on the ball of your foot than you do when landing on your heel.) I’ve been experimenting with Vibram Five-Finger shoes, which I like a lot for running, and since these shoes have no padding whatsoever, landing on your heels
is not such a good idea, at least on rough surfaces, so I was already motivated to change my running style. But I’ll postpone a detailed report on these unusual shoes for another post.

Final notes: (1) If you’re wondering whether the new shoes caused or exacerbated the injury (I was wearing them when it happened), I can’t prove definitively that they didn’t, but I’m pretty convinced that there’s no connection. I’ve tried various shoes since and keep coming back the the Five Fingers as the shoes that cause the least stress post-injury, which is certainly suggestive that they couldn't have caused the injury in the first place. (2) I now know how to go about diagnosing problems like those described above without consulting medical professionals. There are, of course, a lot of good resources on the web that can help you sort through any specific problem. I started out this time with a Google search on “knee pain” and found a number of good diagnostic aids including a paper by Calmbach and Hutchins oriented at Family Physicians that helped me sort through what was plausible and what was not, and I am convinced that I have correctly described the injury. Of course, I have to add the usual sort of disclaimer that you shouldn’t “try this at home” and should always seek competent medical advice when needed. I just happen to have a certain tendency to do things myself anyway, and I’ve come to believe that, in many cases, I can do as well or better than any professionals I might try to hire to help me.


Saturday, June 20, 2009

Third Time’s the Charm? Quicksilver 50K

Being disgusted and frustrated with missing cutoff times in two consecutive races, I couldn’t possibly take the hint, and instead signed up for another one! (against David’s better judgment). It seemed a shame to let all this hill training go to waste, so I convinced David that I was doing another with or without him, and luckily he decided to come too. This time it was the Quicksilver 50K in Almaden Quicksilver County Park in San Jose. We had some vague thoughts about moving up to the 50 mile after returning to the 50K point, which tacks on an out and back to get the extra miles. Supposedly, you can opt up to the 50 mile but not down from the 50 mile to the 50K. Not wanting to take another chance on missing cutoffs or just having a bad day with the heat, we signed up for the 50K with the possibility of continuing on. Turns out, 50K was quite enough on this sunbaked day, and I was happy enough to stop with that.

The picture (pre-race) below was swiped from Donald Buraglio’s site. (Thanks Donald!) David is #117 (currently ~187lbs, down from 220lbs a year and a half ago). Fifty mile winner Chikara Omine is #75. Jean Pommier and Mark Tanaka with backs to the camera. Many other folks I don’t recognize—apologies). For more pictures and a report on the full 50 mile race, see Donald’s post.

The race started at 6 am, before the sun’s rays began to heat us up. We climbed a few initial hills on a fire road, mostly walking where I was, then ran down the road again and off onto a wooded trail following a meandering stream. This section was shaded as the sun rose, and was full of lovely gentle inclines and downhills. At one point I jumped over the stream crossing rather than climbing carefully down and back out again, and strained something in my foot—I thought it was broken it hurt so much! but it gradually settled down. I need to remember that I’m not 20 anymore! We came out onto fire roads again and more uphills, longer though still gradual and runnable, and still mostly shaded and cool.

Reaching the first full aid station (Dam overlook), the sun had only just peaked over the hills. More fire roads with runnable ups and downs, mostly in the shade, and the second aid station was upon us, more brightly lit and exposed to the sun. These volunteers looked to be getting warm. By this point the runners were pretty spread out. A few people had gone out too fast and were slowing down, and I was able to pass a few folks. We came upon Sean Lang and Gordy directing traffic, and soon there was a long fast downhill section leading back to the dam overlook aid station. I tried to make up for my slowness on the uphills here, and to compensate for having to climb this hill again on the way back. This was now mile 19—my energy levels usually start to fade here, and that’s what happened this day as well.

The next section was not difficult and had a fair amount of downhill, but I was just hot, tired and thirsty, and even the downhills felt bad. It seemed to take forever to finish the 4 mile loop, then climb once more to the Dam overlook aid station. I filled up on fluids and wandered off sipping coke on lots of ice. The long downhill became the long uphill as we retraced our steps, and I managed to muster a run here, but it was intermittent. Finally, there was Sean and Gordy again, making sure we didn’t get lost, then a bit more climb and another long downhill to my last aid station. I was surprised to see I had caught someone, and was inspired to try harder this last section. Only 4 miles to go—how hard could it be? It turned out to be the most difficult part of the course! Soon we were climbing again, short steep hills I had read, but what I found were long steep hills almost impossible to climb at this point. My shin muscles were cramping and I had to walk on tip toe to keep the muscles from cramping worse. I felt a shiver and was sure heat stroke was near too. The hills just kept coming and coming until you forget you thought you’d be finished by now. Finally we came upon the final downhill dash (for those who still had their legs) and the finish.

At this point, there was no question about going out into that heat again. I had made the cutoff time for the 50-mile, but it was miserably hot out there on that trail, and the thought of crawling up those last few hills again in the heat was more than I could take. It turned out David had had enough too, and he brought me ice as soon as I crossed the finish line.

And what a spread at the finish! There was watermelon, strawberries, meats on the grill, salads, desserts. They even had a generator for power and a full sized refrigerator (now that's serious advance planning) with ice cream, and they filled ice cream requests to order (I had ice cream with strawberries). It was fun hanging out and enjoying the food with fellow racers. I got to visit with Barb Elia and Christina Brownson, and a whole bunch of other folks whose names I forgot in post-50K brain fog. I also got to run for a while with Janice O’Grady, one of the founders of the event who returned from Colorado to run it. I talked with Mark Tanaka for the first time (having one of his usual hectic race mornings), as well as Simon Mtuy and Jean Pommier. The 50-mile winner, Chikara Omine was amazingly approachable and gracious, though a superstar already at 26 years old. See Mark Tanaka’s interview. And I finally got to see Bev Anderson-Abbs in person rather than merely watch her shoot by (and even talked with her!). She looks like a consummate athlete—lithe and well muscled. Maybe someday…

I was able to keep my heart rate more consistent than at Diablo or Miwok, which could be a sign of some improvement in pacing. I typically start a race between 150 and 160 bpm, and hold that for a few hours, but the HR gradually drops for unknown reasons over time, down to the 140s, and when I’m really dragging or cold, into the 120–130s. It’s an interesting chicken and egg question—does heart rate decline because of fatigue, or does fatigue increase because of HR decline (the heart can’t deliver sufficient oxygen)? The hints I’ve gotten from questioning coaches is that as glycogen is depleted, there is less energy for anaerobic energy production, and the aerobic heart rate is much lower (see the Maffetone formula, that works out to about 135–140 bpm for someone my age and condition. For other lucky souls, it might be much higher and hence they can blow by me without even breathing hard). I’ve been looking through the research literature, but I still don’t understand the connection between exercise intensity, muscle glycogen reserves and heart rate, but presumably it has something to do with blood lactate levels. This time I also didn’t bother with Vespa, though I had tried it previous races. I think if anything, my energy levels were maintained better than usual, but that may have more to do with pacing and the course.

We decided to experiment more seriously with David’s carb-free race nutrition approach, and have him try and run at his own pace to see if he’d bonk with no carbs. So David started out faster and I didn’t see him the rest of the day until the finish. (and I was lonely…) I carried all kinds of food with me, most of which I never managed to eat. Funny how that always happens. I started out with a bottle of full strength Cytomax, but it got diluted as we went along with the watered down stuff. I forgot one of my water bottles, and so never had the ability to carry extra water—when it grew hot, that became a problem. I ended up eating a few gels, few bites of potato and cups of coke, and a couple ounces of roast beef that I brought along in my pocket. Maybe 500 calories in but ~3000 out (walking uses less than running, but 5500 feet of climbing must count for something).

I was happy to be 54th out of 75 finishers and 5th out of 7 in the 50–59 women (not completely back of the pack for a change) in this field that included 19 first ultra runners (many of whom were faster than me!)

David finished successfully without using any carbs in 32nd place overall (and 7th out of 12 in the 50–59 age-group men). He was running with a heart rate generally in the 150s, substantially above the mid 130s that he typically maintains at my pace, and well above his purely “aerobic” effort. Toward the end he reported distinctly slowing at the same heart rate, but that was probably due to a combination of increasing heat and steeper trails and calf cramps. (The hardest hills, both up and down, in this race are at the very end!) He said he couldn’t sit down to rest for about an hour after the race because his legs kept cramping! It was definitely hot there at the end, and I was glad I managed to keep the cramps at bay as well as I did.

The aftermath: the lung irritation and asthma from before Diablo finally disappeared for good (and hasn’t come back thankfully). My foot (that I thought might be broken) was tender and slightly swollen for a few weeks, though I kept running on it anyway, but mostly has settled down again (though the bones look thicker now—got stronger?). Some hot spots on the balls of the feet, but no blisters (thanks to Drymax socks!)