Having SCA3, riding a road bicycle is easier for me than walking. I lack the coordination to walk efficiently, but I can still ride a bicycle under certain conditions, though my ability is dropping precipitously.
How does a bicyclist stay upright?
The bicycle does not keep itself upright in spite of the rider. It’s not the gyroscopic effects of the spinning wheels that keep the bicyclist upright. It is the rider that actively balances the bicycle by steering it. See Jobst Brandt and/or Wikipedia.
Here’s an article from The Popular Science Monthly, Volume 38, published in April 1891 (currently 123 years ago), titled, “What Keeps a Bicycler Upright?”, where the author has it right:
“Gyration has nothing to do with it; centrifugal force has no application to it except when [cornering]….”
“[T]he stability of the bicycle is due to turning the wheel to the right or left, whichever way the leaning is, and thus keeping the point of support under the rider, just as a boy keeps upright on his finger a broomstick standing on its smallest end.”
In other words, staying upright depends on steering. Balancing on a moving bicycle (or on rollers, when the bicycle is stationary and the “ground” moves underneath it) is the technique of oscillating the steering wheel back and forth, thereby keeping your center of mass properly positioned and preventing yourself from falling over.
Please note!
Riding a bicycle requires the ability to balance, and having ataxia will impair your ability to balance and therefore impair your ability to ride a bicycle. I would discourage anyone with ataxia attempting to learn to ride a bicycle or even to get reacquainted with the bicycle after a long hiatus from riding.
My background is that I have ridden many tens of thousands of miles on the road, and I have done bicycle races throughout northern California, culminating as a senior 2 rider in year 1991 at age 23. Now, in 2014 at age 47, after about eleven years of being overtly symptomatic with SCA3, I am at the tail end of my abilities both to ride a bicycle and to walk.
Side note: faking it
In almost all cases of actors riding bicycles in movies, they wobble severely and/or precariously, which indicates an extreme lack of experience riding. They have enough intuitive skill to force their bicycle into submission perhaps even subconsciously, but they have no grace at all. I have not catalogued this phenomenon in any way, but I feel like it happens close to 100% of the time.
Also, I watch a lot of televised bicycle races, and it’s pretty safe to say that all professional riders visibly oscillate; in other words, you can see them steering for balance. They do this even when riding in a pack or close to the side of the road. Perhaps the most extreme case of oscillation (while seated) is my own namesake, the hugely popular Jens Voigt. I recently heard a race commentator wonder how many extra kilometers Jens rode in a race because of his style. There is another big-name rider who is the king of oscillations out of the saddle, namely Alberto Contador.
Interestingly, the riders who hold the steadiest lines are the ones whose fitness level is on the medium to low side. They can be seen around here riding oscillation-free in the three inches between the white line of the lane’s edge and the road drop-off of a narrow road. Even before I knew I had ataxia, I would wonder how they managed to do that.
Riding on rollers
Being familiar with riding on rollers can increase one’s acceptance of how a bicyclist stays upright. To help understand this topic, one need only turn to Jobst Brandt (RIP 2015), as I always try to do on topics pertaining to the bicycle:
https://groups.google.com/forum/#!topic/rec.bicycles.tech/2lo_Hu99p3E
“It doesn’t matter whether [(1)] the bicycle moves forward or [(2)] the road moves backward [as on rollers] for staying upright from steering. The inertia of rider velocity makes road riding more stable but riding slowly is much like balancing on rollers at any speed, there being no forward momentum and inertia of the bicycle.”
“If the front wheel isn’t rotating you can’t steer.” I take this to mean you can steer if the front wheel is rotating.
On rollers, the front roller is connected to the rear rollers with a belt. Thus, the front wheel is made to spin in sync with the rear wheel. This is not important for the gyroscopic effects (except when riding on rollers with no hands) but rather to allow steering and thus facilitate balance. Continuously adjusting steering is how you balance a bicycle, whether it’s moving on the road or stationary on rollers.
Pedaling is of critical importance on rollers. You cannot coast on rollers with any stability (i.e., having the wheels spin as you freewheel); if you stop pedaling, the wheels stop turning quickly due to friction. You will start to fall to the side the moment you stop pedaling, because stopping pedaling also causes you to stop steering for balance. This is especially apparent if you are riding with no hands. If you are riding on rollers with no hands and stop pedaling, you will fall to one side immediately (unless perhaps you have an acrobat’s sense of balance, à la Peter Sagan).
What about motorcycles and animals?
Many principles apply to both bicycles and motorcycles. There are also some significant differences: motorcycles have smaller-diameter wheels, wider tires, and an engine, which greatly affects how you corner.
https://en.wikipedia.org/wiki/Bicycle_and_motorcycle_dynamics
When riding a bicycle, your body’s balance system plays a key role in staying upright, even at high speeds, and the same goes on a motorcycle. Some people with no balance impairment will insist that a moving two-wheeled vehicle balances itself, when in fact it’s actively balanced by the rider. On the other hand, a horse (or other animal) will balance itself; only a machine is balanced by the rider—though in both cases, the rider’s balance is used to keep from falling off.
Bicycling with ataxia
So far here I’ve only covered a bit of riding and balancing on straight, flat roads. I have not yet covered climbing, or cornering while descending. First, here are some general details of my experiences riding with ataxia.
Oscillating
The most obvious side effect of riding with ataxia is needing more lateral room to oscillate (for steering, for staying upright), and I need more and more room as the years go by in order to facilitate my worsening balance ability.
There’s a bit of a conundrum that forms because of this. I would like to stay out of everyone’s way as much as possible, and as a result, I tend to do two detrimental things: when others are near, I try to dampen my oscillations and move to the right. The problem with dampening my oscillations is that it’s at the cost of worsening my balance, and moving to the right makes me nervous if I feel like I’m running out of room, at the cost of getting skittish. The solution, until I determine that I need to stop riding, or get a tricycle, is to try to stay relaxed and assert the modicum of extra lateral room that I need for balance.
How much room do I need? The width of a typical bicycle lane is about right. If there is no bicycle lane, I still want the room.
The need to pedal
To facilitate oscillation, which facilitates steering and thus balance, I need to be pedaling. If I’m not able to rhythmically oscillate at a reasonable cadence, then I think I’m relying more on my vestibular system for balance. When coasting, the steering corrections needed are slow and subtle, and with ataxia, I’m losing the proper feedback between my vestibular system and cerebellum, especially when subtlety and precision are required.
When cornering, the need to oscillate is put on hold entirely; more on this ahead.
With ataxia, sudden balance corrections are becoming more difficult. I need to be able to respond to external forces such as the wind, and that’s more difficult when coasting than when climbing and cornering. When I’m climbing or cornering, I’m more actively involved with maintaining my balance. Earlier in my SCA3 progression, I generally felt safe coasting, though doing so on straight downhills mixed with high-speed traffic and crosswinds could make for harrowing moments because of needing to correct for the random (and strong) forces of the wind knocking me around.
My need for pedaling-induced oscillations is now (i.e., recently) more necessary than ever, and I try to avoid coasting even on extremely shallow descents. This is perhaps my most difficult issue to deal with yet, and it may be my undoing. I am finding that braking also facilitates steering and thus balance (at least a little), which works well because both braking and reaccelerating are balance-inducing moments. Also, pedaling with the brakes on works well to facilitate balance, though that is a bit tiring on the hands.
The need to pedal is best met by climbing; more on this ahead.
Vestibulo-ocular areflexia
A big problem on the bicycle is my vestibulo-ocular areflexia, which even among the SCAs is specific to SCA3. Normally, the inner ears (the vestibules) and the eyes (the ocular system) work together, so that you can look around while walking or riding a bicycle, and your cerebellum is able to combine all your sensory data usefully, accurately, and instantaneously. This is known as the vestibulo-ocular reflex, or VOR.
Because of my sluggish eye muscles (i.e., ophthalmoparesis, leading to areflexia) and possible miscommunication with my cerebellum, moving my head causes my inner ears and my eyes to get out of sync. There’s a noticeable time lag between them, and the worsening of this is that they never really sync up. This lag effect is very pronounced on a bicycle when moving my head to look one way while my body moves in another direction.
Two things quickly became impossible on the bicycle: physically looking behind myself, and looking left while turning right. For a good number of years, the solutions to these problems have been:
- Using a rearview mirror. https://www.amazon.com/dp/B000C17M26/
- When turning right and needing to look to the left, I simply stop, look, and then go. At extremely quiet intersections, most cyclists may simply slow, look, and go, but I need to stop, look, and go. I only need to do this at stop signs and red lights, so it’s the more law-abiding approach anyway.
I’m fairly lucky that I can effectively use the mirror to avoid turning my head. Minimal head movement and minimal eye movement are needed to use the mirror. Because the mirror is sitting nearly directly in front of my left eye, the primary physical action I need to take is to refocus my eye(s).
Accommodations (summary)
Ride with a rearview mirror (details above).
Stop to look (details above).
Ride on wider tires. A few millimeters of tire width may sound like nothing, but riding on 700×28 tires makes a noticeable difference compared to narrower tires (i.e., my balance feels more stable).
Go on shorter rides. As the years have gone by, I’ve needed to keep shortening the duration of my rides. The effort it takes to balance feels mentally exhausting more than anything. A few years ago, I was able to ride for four hours at a time. Now, I am down to 90 minutes.
Other difficulties
Riding with less than two hands on the handlebars is unstable, though it depends on what I’m using my off-bar hand for. In 2010 at age 42, I was commuting to work on a bicycle with downtube shifters, which was challenging but I was able to shift okay. I doubt I’d feel as comfortable now in 2014 at age 47. I’m currently only riding a bicycle with brake-lever shifters.
Putting a water bottle back into its cage is almost impossible now (though I do it if no one else is around), as is proper signaling with my arms and hands. In the old days, I was the most law-abiding and conscientious bicyclist on the road (seriously!), so it breaks my heart that I am unable to signal properly now.
In 2010 at age 42, I felt comfortable riding in heavy commute traffic with many stoplights. I no longer put myself into that situation, but I also know that I wouldn’t feel comfortable doing it now. “Threading the needle” through drivers blocking the bicycle lane would barely be doable now.
Something that breaks my heart is knowing that skittishness looks like lack of experience. I know that as the years go by, I look more and more like I’m someone with a lack of bicycle experience.
Things that still work
I am still riding with cleats and clipless pedals.
In 2014, the coordination required by me for circular pedaling is not impaired at all (whereas the coordination required by me for walking is completely shot).
Climbing, and ataxia
Climbing is the only reason I’ve ever liked riding. Thankfully, climbing is the easiest to still do at my level of ataxia impairment. Though I hate descending, doing it on curvy roads is easier than riding on flat roads, so as long as there’s minimal traffic, hills still are my friend.
When climbing in the saddle, I generally grip the tops of the handlebars firmly, especially if it’s steep. This means that with every pedal stroke, I am the most engaged with the process of balancing the bicycle that I will ever be (in the saddle). At my stage of riding with ataxia, climbing (in the saddle) is when I feel I have the best and safest balance.
Climbing out of the saddle is still doable, though I try to avoid it. It requires a tremendous amount of mental energy, and the hardest part is transitioning back onto the saddle without jarring my balance during the process.
Cornering on descents, and ataxia
Cornering on descents could be another lengthy topic, but I’ll try to keep it short. When turning to Jobst Brandt on this topic (no pun intended), he tells us, I think, that the only important factor when cornering is the lean angle.
https://sheldonbrown.com/brandt/descending.html
As far as I can tell, Jobst considers all the advice out there about body position, center of mass, and countersteering to be irrelevant noise; the only important factor is lean angle, and everything else is psychological or intuitive. I still think it’s worthwhile to acknowledge these other factors, especially in the context of having a neurological impairment that takes one off of autopilot and degrades one’s ability to do them.
How does having ataxia affect my ability to corner?
- Broad, sweeping corners, with no traffic worries, are wonderful. I feel little impairment.
- Hairpins and slow corners in general are not fun. I need to readjust my line many times and therefore need to take them slowly and easily.
My need to oscillate goes away when I’m cornering at somewhat high speed, which I believe is what is supposed to happen because of the centrifugal force involved. I think this means that when I’m focused on shifting my center of mass for cornering, that is all the active balancing that I need to do, and I am still able to do it. It seems to require little physical coordination to corner.
Rollers, and ataxia
Rollers and ataxia don’t mix. A few years into my symptoms, I rode my rollers as a steep challenge to myself. After a few days of reasonable success, I decided to push it and tried riding with no hands, and fell off—I’d never fallen off before. It was a rather unpleasant fall onto concrete, and I sold my rollers shortly thereafter. It was absurd to keep doing something that dangerous.
What does it all mean?
I think my experience with ataxia (so far) shows that it primarily affects the complex coordination required for walking and maneuvering on foot, and the circular motion of turning cranks on a bicycle requires less coordination than maneuvering on foot.
Furthermore, I feel that my ability to balance my center of mass is still mostly intact. It’s my impaired walking coordination that prevents me from being able to balance my center of mass when walking, but I feel that I can still intuitively keep my center of mass balanced on a bicycle.
In other words, it’s easier to properly orient my center of mass on a bicycle than on foot. True, having an impaired vestibulo-ocular reflex is a bummer. If it weren’t for that problem, perhaps I’d be close to fully functional on a bicycle.
Updates
2014-08-14, nearly age 47: last hill climb.
2015-07-19, nearly age 48: last (flat) ride.
2022-02-24. My latest wheels =
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