PowerCranks blog (LONG)

Triathlon Forum
1

I initially wrote this blog for my coach to discuss the need for changes in my riding position. I thought that I could post it here as well and maybe get comments from some of you experienced PowerCrankers.

I’ve been training with the PowerCranks exclusively for about 5 weeks now. Yesterday I did a 2 hour indoor PowerCranks session which is by far the longest session yet.

I’ve noticed that my hands get sore and that I have to keep changing hand position when riding with PCs. On my shorter rides I have not given this much thought and I have blamed it on trying to keep my hip angle open. On this long ride I realized that I am carrying a lot more of my bodyweight on my arms than when riding with regular cranks. My shoulders and wrists were quite strained and my right pinky is still a bit numb from the pressure on my palms.

Why is this? I haven’t changed the bike geometry or riding position.

**** When riding with regular cranks both legs apply downward pressure on the pedals. Even though I have worked at pulling up or pedaling in circles with regular cranks there has always been a net downward force from the “recovering” leg on the pedal. This force has been equalized or countered by the “driving” leg that both apply power to the rear wheel and lifts the “recovering” leg. When riding with PCs the connection between the crank arms is removed and the recovering leg is forced to apply a net upward force on the pedal. Consequently the driving leg applies less downward force for the same amount of movement. The rationale for the PCs is that this is a more efficient way to propel the bike forward.

There are 5 points of contact between the rider and the bike and the riders bodyweight has to be distributed between these. When we reduced downward force from both legs using the PCs, the legs carry less of the riders weight. This load is consequently moved to the seat and hoods. At the same time we removed some of the riders “grounding” and balance obtained through balanced downward force applied by both legs. The way humans are built we are most efficient when both feet are grounded and in balance. For example a boxer hits much harder if he is properly grounded and when you try to open a stuck door you rely on power transfer through your core and your grounded legs, not the arm that opens the door. The point is that when riding with PCs the legs are less grounded, one is actually pulling up and further causing imbalance. Because of this we are not able to transfer power through the core to stabilize the upper body and hold it erected as easily as with normal cranks. The result is that the weight removed from the legs is now carried by the arms and not increased weight on the saddle as you would initially think.

This effect can be countered by mashing bigger gears as this will increase the downward force on the pedals. This also explains why it is more comfortable to ride at a harder effort while using the PCs, independently of cadence. A harder effort implies more force applied and hence it is possible to engage the core muscles and unload the arms. With regular cranks it is possible to cruise at a low effort. With PCs the “drive” leg just drops to the bottom of the pedal cycle if there is no resistance providing support for the body weight. This resistance is provided by the “recovery” leg using normal cranks.

This also explains why it feels very far to reach the hoods when riding with PCs. I’m much more comfortable riding with my hands on top of the bar because my body is less “cantilevered” out. The more erected, the more weight is directly applied to the saddle and hence I rely less on support through the core.

Riding in the aerobars is a special case. This is incredibly tough because when I close down the hip angle, the hip flexor is left with a very limited and unusual range of motion to pull the leg over the dead spot. Almost like getting up from a deep squat is much harder than if you only go down to 90 deg knee angle. Although this is the most apparent effect, and certainly the perceived effect, I am sure that the reduced “grounding” worsens the problem. I think that my pelvis tilts forward more due to the lack of core support, further closing the hip angle.

Will all of this improve with training/adaption? Will I learn to engage my core muscles and unload my arms in the roadie position and open my hip angle in the aero position? Will I have to do drastic changes to my riding position(s) to adapt to the PC riding style?

 I hope this is food for thought! 

 Sindre
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2 hours on a trainer with PowerCranks? Gracious, that’s tough. I’ve had PowerCranks on a road bike for nearly 2 years. I’ll say that after a while (more than 5 weeks), your rpms come back up (especially if you work on that) to more normal levels, and the hand pressure you may be finding as a way to compensate for what you see as a weak core, will lessen. THEN, you may start to see an increase in seat pressure. As you progress even further, that increase in seat pressure tends to lessen as you balance the pulling up with pushing down a bit harder. You do need a strong core to stabilize the pelvis to do this, it takes some time. I know that when my lower back or sides are sore (for whatever reasons), I have a harder time riding PCs, and lots of things become uncomfortable in a hurry. I’d say you’re asking you body to do a big load in only 5 weeks, but, as long as you don’t get hurt, it’s a good way to get much of the initial adaptation done. Maybe break that 2 hour ride into two 1:15’s!

How’s your run coming along?

3

Don’t worry about that, eventually you’ll adapt to Powercrancks and become really good at riding Powercrancks, which will give you an enormous satisfaction and sense of accomplishment.

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I agree with your analysis. It sounds to me that you are doing well in your adaption if you can ride for 2 hours on a trainer at 5 weeks (which is a lot harder than 2 hours on the road). Riding on the trainer is probably more painful also as the bike doesn’t shift under you as much, giving you less “break” in position.

One thing you need to consider is what you are doing with your hands. If you are not relaxed, because of the PC’s or whatever, then that can cause problems with your hands also, beyond the extra weight on them. The muscles need to be relaxed to get blood flow and if the blood flow is inadequate you will get pain and cramping.

Regarding your last questions: "Will all of this improve with training/adaption? Will I learn to engage my core muscles and unload my arms in the roadie position and open my hip angle in the aero position? Will I have to do drastic changes to my riding position(s) to adapt to the PC riding style? "

Yes, Yes, and probably not unless your previous riding position was poor. The adaption occurs mostly and naturally from time in the saddle, not from changing riding position. That being said I think many make minor or subtle changes, especially in the first year.

5

Don’t worry about that, eventually you’ll adapt to Powercrancks and become really good at riding Powercrancks, which will give you an enormous satisfaction and sense of accomplishment.

So true…

Sindre does have a point though that I think is often overlooked. Folks often talk about the importance of flexibility in being able to maintain an aggressive riding position for long periods of time. Even the most inflexible person can touch his thighs to his chest with a 25 degree bend in his knees without too much trouble. I think it’s those with the fitness to put a lot of force to the pedals on the downstroke for extended periods that are most comfortable maintaining a closed hip angle for long durations. If you’re not supporting much of your weight through your pedal stroke, it’s going to be difficult to stay comfortable on a bike.

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Don’t worry about that, eventually you’ll adapt to Powercrancks and become really good at riding Powercrancks, which will give you an enormous satisfaction and sense of accomplishment.
By that I assume you mean that I will just get good at riding Powercranks, not at riding a regular road or triathlon bike? :slight_smile:

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I’m not saying anything more, I want this thread to remain quiet :slight_smile:
.

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I’m not saying anything more, I want this thread to remain quiet :slight_smile:

Why on earth do you care? If it wasn’t for you and a few others the PC threads would be like all others.

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Frank, it was a JOKE… hence the smiley… you know I love you in the purest Tibbsian way :-)))

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This problem with the servers has got to end, LOL
.

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Regarding “grounding,” balance and core strength…

Your body will hold back on the power it allows you to deliver to the pedals as long as you feel awkward or out of balance. You are correct that the loss of pressure on the bottom of your foot (on the upstroke) creates a core challenge. That’s a GOOD thing. I use unbalanced and unstable positioning with all my athletes who can handle it, because it creates TRUE core strength. By that I mean transversus and pelvic floor, not just six pack and obliques.

The improved core strength will make you a better rider, and two hours on PCs will improve core strength.

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Assuming Sindre’s premise is valid and a PC rider supports more of his/her weight with hands/arms and/or has to ride more upright, how does that contribute to ‘core’ strength building? The more weight that’s supported by the hands and arms and the more upright the rider is on the saddle, the less the muscles of the ‘core’ are being used to support the weight of the rider’s upper body. No?

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“how does that contribute to ‘core’ strength building?”

The true “core” is the transversus and the pelvic floor. The “decorative” abs are secondary. Whenever you are unstable (physically, not like Tibbs!) your transversus engages to stabilize the spine, and the pelvic floor muscles engage to support the internal organs. It is these that are largely responsible for our ability to balance and stabilize under load. As an experiment, try doing your normal curls, shoulder presses and reverse flys, then try doing them balancing on one foot. You’ll feel the “core” muscles working. You’ll also find that you’re initially much weaker until you learn to stabilize.

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“how does that contribute to ‘core’ strength building?”

The true “core” is the transversus and the pelvic floor. The “decorative” abs are secondary. Whenever you are unstable (physically, not like Tibbs!) your transversus engages to stabilize the spine, and the pelvic floor muscles engage to support the internal organs. It is these that are largely responsible for our ability to balance and stabilize under load. As an experiment, try doing your normal curls, shoulder presses and reverse flys, then try doing them balancing on one foot. You’ll feel the “core” muscles working. You’ll also find that you’re initially much weaker until you learn to stabilize.
The erector spinae working to support the upper body in the sagittal plane doesn’t count?

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I still recall the soreness in my lower abs when I first trained on PowerCranks. As far as core muscles and PCing go, wouldn’t anything that causes your pelvis to become unstable work some of these core muscles? It’s common to see new PC’ers rock their pelvis side to side (and even fore-aft) trying to help the hip flexors get the knee up. I would think the Erector spinae would be worked like normal, and then called on a bit more to stabilize the lumbars when PC training, because the Psoas attatches on the ventral-lateral surface of the lumbars. As the psoas and illiacus contract to flex the femur, it tends to pull the lumbars ventrally, the erectors would be called on to stabilize that ventral movement tendency.

I have a recurrent quadratus lumborum injury that really makes PC training difficult/impossible when it flares up. All these muscles are inter-related, maybe one of the ways PC training benefits some people is that it strengthens these muscles, and their relationships to one another, when stabilizing the body during pedalling.

Could it be that the non-circular pedalling advocates are correct? Perhaps the PC “circular pedalling” isn’t the best pedalling strategy…but, since so many people report improvements, maybe it is due to this “core strengthening” and/or other training effects?

I don’t claim to have the answers, just theories and questions. And, I’m one that is going to continue my PC training because, for whatever reasons, my performance improved measurably.

17

“I have a recurrent quadratus lumborum injury that really makes PC training difficult/impossible when it flares up.”

    • Wow, that’s a hard one to injure. Is it tight, possibly from a related injury, or is the injury actually to the QL? Often QL problems are the result of postural distortions that can be corrected with some work. I wouldn’t try to diagnose or prescribe over the Internet, but a good chiropractor or PT might be able to help you. (I have a back injury dating back nearly four decades that left me with some problems, and in compensating, my QLs have gotten quite short and quite tight. It takes working at it on a regular basis to keep them cooperative.)

“All these muscles are inter-related, maybe one of the ways PC training benefits some people is that it strengthens these muscles, and their relationships to one another, when stabilizing the body during pedalling.”

    • Absatively. The instability makes the stabilizers work like mad.
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“The erector spinae working to support the upper body in the sagittal plane doesn’t count?”

Erector Spinae would count as core, but I wouldn’t include it in what I’m calling the “true” core, or the stabilizing muscles whose primary function is stability rather than movement. I would include the multifidus, however. Meanwhile, the spinal side of the equation isn’t going to be stressed as much, because you still have your arms and the handlebars to help keep you from falling into your front wheel.

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Yep, it’s the QL alright. Initially diagnosed by an orthopod, seconded by a chiro years later. Yep, it’s tight! Yep, I have some related postural imperfections. Yep, it’s a bugger to have to deal with periodically. It’s not a big muscle, yet, like a little toe, it hurts like heck and affects the whole shebang when it does get overly stressed.

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Yep, it’s the QL alright. Initially diagnosed by an orthopod, seconded by a chiro years later. Yep, it’s tight! Yep, I have some related postural imperfections. Yep, it’s a bugger to have to deal with periodically. It’s not a big muscle, yet, like a little toe, it hurts like heck and affects the whole shebang when it does get overly stressed.

What effect does weights/resistance training have
on that area?

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If I forego weight training, or more specifically, lower back training, and just ride, I’ll be in a pretty bad way in about 2-3 weeks. Running seems to not bother it much, unless it’s already hurting. I do straight-legged dead-lifts with very light weight and high reps, several lateral raise things that hit it from different angles, superman poses, and a three-point based balance ball exercise. As long as I’m diligent with it, it causes little problem. It’s when I ignore doing the right things for a while that I get all bent out of shape there. I’d never encourage my child to play football, unless they were driven to play (as I was). Lots of the injuries I incurred in that sport still haunt me today…amazingly, my knees weren’t ever seriously injured!