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How 3mm Saved my Dirty Kanza: Co-Founder Bagg Checks in from the Gravel

Bagg Little Egypt Exit Cropped.jpeg

all images courtesy Steve Driscoll at Lift Creative Studios

Not long after the above photo was snapped, slightly under halfway through the 202-mile affair that is Dirty Kanza, both of my hamstrings started cramping, just above and to the outside of my knees. Cramping is something many of you have experienced, and it’s certainly not what you want to have happen when you’re still looking at about 100 more miles of riding in the early-summer Kansas sun. I slowed to a halt, swung a resistant leg over the saddle, pulled out my multi-tool, and raised my saddle about three millimeters. I continued on. The cramping, while not totally fixed, improved, and stayed improved enough for me to finish the race in eleven hours and fifty minutes and 22nd place overall, right around my goals.

So what happened? What magic voodoo did I perform that saved me to ride a second-century across mostly gravel roads? First we’re going to get into the actual mechanism of cramping, and then I’ll explain the fix.

It’s Not Just About Dehydration

I was dreaming of pickle juice for most of the ride

I was dreaming of pickle juice for most of the ride

I can’t tell you the number of people who default to hydration and electrolyte levels when they hear stories about others cramping, and the big nutrition companies will certainly try to sell you on this angle. The truth is that cramps aren’t well understood from a clinical perspective (isn’t that marvelous? We can go to the moon but the human body is still a place of adventure and mystery), and a series of mechanisms contribute to muscles cramping (note that I said contribute—there is no single smoking gun). At Dirty Kanza I consumed close to 600 oz of fluid over the twelve hours, along with almost 6000mg of additional sodium through salt pills. I was peeing regularly throughout the event, and peeing clear—in short, I’d nailed the hydration side of the race.

But this doesn’t mean dehydration and electrolyte depletion don’t contribute to cramping—they do, and you should make sure that you hydrate as assiduously as I did over the course of your next race. I’m just highlighting the fact that that wasn’t the big cause.

Fatigue and Weakness

A cramp is really just a confused muscle. Muscles get tired through over-use, and eventually they kinda lose it, sorta the way that you do when you’re tired and hangry. When they lose it, they just start contracting randomly, like a pissed-off toddler. You can generate fatigue by going too hard too early (sound familiar, anyone who has walked the back half of an Ironman Marathon?), or by doing more than the muscle is prepared to do. Weakness, on the other hand, is just the other side of fatigue. If you’ve shown up with a muscle that isn’t prepared for your event (i.e.: it’s too weak for the application), it’s going to get fatigued sooner and start cramping. The takeaway? Prepare correctly, don’t go out too fast, and ride within yourself. I think I had pulled off those three things, although my volume going into the race (186 miles/week for 16 weeks prior) was on the low side of acceptable—so there’s a possible pathway here for me.

Prior Injury/Trauma

This is what I think contributed to my cramps. I’ve had scar tissue build up in the short head of my biceps femoris for some time now, leftover from the last few years of my triathlon career, my odd run form, and my bike fit issues before I meet Steve Merz at the original Output. These muscles, on both sides, are tight, and they feel kinda like rocks to the touch. They gross out my massage therapist. The biceps femoris is one of the muscles that controls the motion of the knee: in particular external rotation of the tibia (your shin bone). This is a movement you make thousands of times when you ride your bike (100 miles into Kanza, for example, at 80 RPM I had flexed the knee almost 29,000 times). My scarred up biceps femoris didn’t like it, and started rebelling—cramping.

Nervous System Issues

If a cramp is just a confused muscle, sometimes the signal to the muscle is the issue, which is why you’ve seen, in recent years, a proliferation of products designed to help your nervous system function properly during long-distance events. Just as with fatigue, your nervous system gets tired, too, and sometimes the signal gets scrambled. I believe that this is happening for me as well—I’ve got some lower back issues that press on the nerves that run to my lower body, sometimes resulting in crazy signals and cramping. The tightness/scarring of my biceps femoris (see above) also contributes, here, as it inhibits the nerves around it. The best thing you can do here is the physical therapy program your PT has prescribed.

So What Was Up With the Saddle Height Change?

I knew that too much knee flexion could contribute to my biceps femoris cramping, since it means my knee angle, both at extension (knee at the bottom of the pedal stroke) and flexion (top of the pedal stroke) was not enough and too much, respectively. Why wasn’t my saddle higher to begin with? Well, I also have some upper hamstring issues and lower back troubles, and putting the saddle too high will make those areas angry. I figured that I should address the problem at hand, and fix the big flashing warning light. The result? Within a few miles the cramping receded, although little ghosts of cramps flitted around the muscle for the rest of the day.

Long Term?

I’m going to keep the saddle height for now, and aggressively try to fix the tightness/scar tissue of the biceps femoris. That means strengthening all of the hamstring complex, and doing my PT every morning. It’s amazing how often that is the answer to our physical woes. But having a proper bike fit, and understanding the interplay between saddle height and muscular function, allowed me to make the change on the fly, and hopefully this will inspire you to ask some of the same questions of your bike fitter. We like to say comfort = power = speed, but in this case it was knowledge = comfort = power = speed, which doesn’t have the same ring, but does have the same outcome.

Bagg at the finish, covered in salt but not cramping

Bagg at the finish, covered in salt but not cramping

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