Uphill stress test: using my "bum leg" as a realtime strain gauge

Only about three weeks after the calf "re-pull" going up Lafayette, my leg was feeling quite a bit better.  I had even been out for some fairly gentle walking-around in the meantime, paying close attention to any hints of discomfort that the calf or Achilles might produce from any particular kind of stress.  Muscle/tendon tears generally take six weeks or more to heal, and may not get fully back to rights even then depending on original severity and subsequent care.  Fortunately, my "recurrence" was less serious than the original injury back in December, in part because I knew what was happening and knew to get OFF it as much as possible right away, and then made sure to take better care of it afterward.  But I wasn't going to just sit around and do nothing, in the height of get-outdoors season.

As a first-level test I decided to try the AMC-organized "Thursday evening conditioning hike" in the Fells, but instead of going with the group I started at the other side of the loop and went the opposite way from their usual direction.  And I did indeed meet the group along the way, twice as we circled our different directions.  That was useful, as we could chat briefly and I could let them know that I was starting to get back on the trails, and I wanted to test myself on the same type of energetic hike but not burden them if I did have a problem and needed to limp out of the woods.  I felt pretty solid on it and blitzed the four miles at a good clip, even though I could still detect a little weakness, or something not 100% right, in the calf.  Nothing actually *hurt* or felt like it was going to let go again, and I seemed to have most of my "launch power" back already, so now I wanted to tackle something a little more strenuous.

Recalling what the barefooter in the 2015 article about Welch-Dickey had mentioned about other trails, I decided that my second-level test would be to go give South Moat Mountain and its sharp "shale-like" terrain a try -- just to see what she'd been referring to.  This trail only ascends about 2200 feet and isn't inordinately steep for most of the way, and I would be super-careful and pay attention to what my body was telling me.  I drove up on a nice Sunday morning, hoping that it would be a somewhat less popular hike on a weekend [not being a 4K, or the nearby "hot target" of Chocorua].  I guessed right; there were still several slots open at the trailhead parking at about 10:30 when I finally rolled in.

  Deep diagnostics

So on this ascent I was able to really Do Science.  My leg in its not-quite-healed state could function as a sensitive "abuse detector" and give me fine-grained feedback about what I was doing, and the mountain had just enough elevation gain that I'd be putting forth a nontrivial effort.  This would partially re-create the conditions of going up Lafayette -- a level of general fatigue, and lots of large upward steps.  One major thing I'd noticed all along was that stepping off with the right foot angled upward in a dorsiflexed position produced the sharpest feeling of something amiss in the muscle, so I was trying to mostly avoid that.  There's a moment in a step when the rear heel lifts and the foot helps propel forward, with the knee straightening out at the same time.  That places a brief peak of stress on the calf and Achilles, and the more lengthened the system already is, the more strain that is.  On typical rocky/rooty trail sections some amount of that happens anyway, but while I could feel a difference today when my heel was momentarily hanging off a rock, I was healed up enough that it wasn't causing distress or any notable threat of failure.

However, I did make a few key discoveries as I began to tire out, and was able to relate most of them back to the Lafayette ascent.  Mainly, as more "burn" crept into my quads and glutes, my steps became a little more lurchy, if that's a word.  There's a natural tendency we have, when a motion has to overcome a lot of resistance that a muscle group feels less ready to deal with, to try and jerk the motion a little more and use inertia to carry it through.  One obvious manifestation of this is seeing someone do heavy bicep curls wrong, where they're throwing the whole upper body back and forth to try and help the arms lift the load.  Similarly, when my legs started to feel less able to power smoothly through large upward steps onto the uphill leg, I found myself almost involuntarily trying to hop off the rear leg a little to help move upward onto the front one.

And *that* was the killer -- the one key motion that I could feel was going to make bad things happen if I kept it up too much.  It's a natural gait adaptation, to shift load away from parts of the body that are becoming less able to deal with it -- except that now I needed to intervene and keep it under control.  It was during this scenario that I got the day's one or two small warnings that things were pushing the limit -- when stepping up with the left leg, and having my right leg automatically try to explosively "dyno" my whole body up onto the next big upward step.  That fast twitch with the rear foot already dorsiflexed was the absolute peak stress point, and I was remembering the same feeling from the Lafayette climb just before the right-side Achilles started to hurt.

So the answer, at least for finishing my Moat ascent, was to *stop* and rest a bit and have some more water, maybe palpate the calf a little, and not be in such a hurry that I'd just blow out my drivetrain again.  In other words, to not let the engine overheat and seize up.  It's also worth noting that I'm not exactly in my twenties anymore, and said engine has its share of miles on it.  I forcibly decided that if I couldn't step up smoothly and let either rear foot just follow along without trying to "helpfully" impulse, it was time to slow down or stop and let the rest of the system recover enough to do its job. 

As I worked with this, I mulled over all the other contributing factors from Lafayette that I was able to recall, observe, and even partially reproduce today.  I *was* quite tired during that previous big ascent, about to reach the summit, and likely not giving myself enough time.  I had more more pack weight that day, including the fact that I had just refilled my 2-liter water bottle back at the hut -- 4 more pounds.  The steps upward over the rocks were big, and I had definitely started reverting toward whole-body launch movements over them to continue the effort, including that calf-killing back-foot hop.  Another compensation I remembered from Lafayette was that I'd started trying to assist my legs by pushing down on my knees -- another natural tendency, but obviously placing even more strain on the lower legs.  This is where trekking poles might have helped somewhat -- if one is going to try and bring arms into a climb, their force should be directed against the terrain and not one's own already laboring body parts!  What I should have done that day on Lafayette was stop, sit down, and cross-fiber massage that Achilles and figure out what was going on.  Later that same day, I had also realized that it wasn't just my right leg that was getting hammered on, especially after I'd gone into "limp mode" for the rest of the trip.  The left Achilles had also been rather sore as I recovered from that trip, albeit thankfully not pulled despite the additional load it had to deal with at the time.

One could try to argue that big stiff hiking boots with "support" might prevent so much foot dorsiflexion, possibly mitigating the stretch factor in the gastrocnemius/soleus system.  But the hopping tendency would still be present once fatigue sets in.  Besides, a lot of people climb in trail-runners nowadays because they *want* the flexibility over uneven surfaces, so they're probably going to bend their feet upward about as much as they would barefoot anyway.  What I also know from this experience is that the "impulse launch" cannot be simulated by doing calf-raises with the ball of the foot on a step, even if that is a good overall strengthening exercise.  Even in my recovery period(s) I could do those fairly early on and not feel any notable warnings, but the simple process of fast walking on flat ground yielded a totally different weak feeling in the leg.

So my experimental Moat jaunt was quite fun, and informative.  After summiting South I continued on toward the vague area that's supposed to be Middle Moat and tried to find the peak, but there are three or four high points all around the same level.  My summary of the day was "lovely ledges and bountiful blueberries", as the latter were in *peak* season and I spent quite a bit of time picking and eating along the way.  The descent back to parking was completely uneventful, and if I was feeling any particular subsystem more than others later it was my knees.

  Some generalizations

So I'll summarize a few things that are useful to remember while hiking in mountains with meaningful elevation, especially when barefoot.  These aren't just about avoiding excess strain, we also want to avoid other potentially damaging actions.  Obviously, the "dorsiflexed dyno" move done to excess is potentially bad, and in a fairly sneaky way if you aren't paying attention.  Never forget that gravity sucks, foot-pounds are real work, and the climbs will be slow.  Becoming excessively fatigued in general can bring more risk of numerous musculoskeletal problems, especially as compensation mechanisms we aren't normally used to start kicking in.  I've learned that briefly resting in a full squat position helps keep flexibility up in the knees and ankles, and if any hint of cramping is felt during that process then I probably haven't had enough water.  We obviously need to take note of pointy items ahead and avoid stepping onto those, but not in such an obsessive way that we spend the entire day looking down.  Another thing I've found useful is remembering to lift the feet fairly high after each step -- especially downhill, to avoid kicking any roots or rocks sticking up.  That works against another tendency that comes with being tired -- to just skim the foot forward just off the ground instead of lifting over anything that might be in the way.  Smacking a toe or forefoot-pad into something is a good reminder, of course, and trying not to trip obviously holds for the shod hikers as well.

One way to think about the combined gait picture is to watch the way a dog moves its front feet when walking -- the leg comes fairly high off the ground, and the "wrist" flexes back for a lot of clearance before the next placement -- and then that placement is straight down.  Of course our feet are more the equivalent of a dog's hind feet, but without their advantage that the front paws have already figured out what the path forward is like.  I try to think of my feet as attached to a wheel, or pedals, going around in a nice big vertical circle instead of a flat shuffling motion.  This also leads toward a generally forefoot placement and a more "foxwalking" type of gait, which is very stable and also best for quickly sensing what's on the ground before commiting to putting full weight on it.  We all naturally do that when barefoot on rough stuff anyway, even those of us with the most trail-toughened soles.  The motion also tends to reduce that rear-foot launch impulse a bit, as well as lending more range of motion to the knees which can help keep them from stiffening up as much on the downhills.

Once these subtleties become more habitual and natural, the rewards of tackling big-mountain hikes in the boots we grew ourselves almost cannot be overstated.  Understanding our own locomotion systems and their limits at a deep level gives us more assurance that we'll have a great day out.


_H*   190813