Handle Bio-mechanics

[johnlvs2run]

Robert,

Great work. Thanks for sharing.

Concept2 should hire you and Warren Berger as consultants.

Is there any significant reduction in weight?

I have no problem reading the monitor from its new location atop the flywheel housing.

The monitor looks to be above the chain, the same as previously.

[Slidewinder]

Hi John,
A friend gave me this old computer - and I can't view my posted image with it either. I'll look at your design the next time I'm at the local library.
Robert

[Slidewinder]

Re: Geometry and the Slidewinder handle
To start with the most basic bio-mechanical design consideration, try this:
Grip a pencil in your hand and then hold your hand out in front of you. Relax your wrist - not limp - just let your wrist and your hand assume a natural and relaxed position. You will notice that the pencil in your grip is not at a right angle to your forearm. It is at a slight angle. Whether you hold your hand horizontal, vertical, or anywhere in between, the pencil remains at a slight angle to your forearm.

I didn't discover this. Every manufacturer of handguns knows this. That is why the handgrip of a pistol is not perpendicular to the barrel, but at a slight angle. It is the most comfortable and ergonomically correct position.

In an earlier post I described the ergometer handle as a human/machine interface, and defined a successful human/machine interface as one that creates as seamless a connection as possible between the human and machine. The machine should adapt to the human, not the other way around.

The primary goal therefore, was to design a handle that maintained that pencil-in-the-hand angle under all possible user conditions:
- to maintain that angle whether the user's hands are horizontal, vertical,
or any position in between
- to maintain that angle from catch to finish, whether the user starts with
the hands horizontally aligned or vertically aligned (hand over hand)

"But wait!", I hear some rowers sputtering, "Rotating your hands to vertical has nothing to do with rowing!"
To this I reply, "So what?"

Having the capability to move in a certain way is not the same as being forced to move in that way. God gave Adam and Eve freedom of choice. I would like to give ergometer users the same freedom. If the freedom to engage in non-rowing related movements does not in any way limit or diminish the rowing enthusiast's ability to exercise using rowing-specific movements, then there are no grounds for dismissing or criticizing what is actually, a broadening of the appeal and potential of the machine.

I have no statistics, but I would not be surprised if more non-rowers than rowers now use the C2 ergometer. They use it for the general health and fitness benefits of the exercise, not to improve their rowing performance. Being able to exercise using a variety of stroke geometries, both rowing and non-rowing related, would be very attractive to this large and growing group.

For almost thirty years, the primary obstacle to users being able to experience and enjoy the full potential of the C2 ergometer, has been the primitive design of the handle. The user of the stock handle is restricted to one movement - and even that one movement is bio-mechanically flawed.

In another post I will explain how the specific geometry of the Slidewinder handle enables, not just a choice of movements, but in doing so, meets all of the described human/machine interface objectives.
Robert

[bloomp]

I have no statistics, but I would not be surprised if more non-rowers than rowers now use the C2 ergometer. They use it for the general health and fitness benefits of the exercise, not to improve their rowing performance. Being able to exercise using a variety of stroke geometries, both rowing and non-rowing related, would be very attractive to this large and growing group.

I think "use" is a very relative and generous term. Most people don't know how to properly USE the ergometer at all. Most people don't want to put in the effort to learn HOW to use it either. They won't be doing themselves any good rowing for 1 minute at an all-out pace with terrible technique, and they won't be doing themselves any good using weak-terrible technique to row at 2:30+ pace for 2k. That's not fitness. I've never seen ANYONE actually put in a workout on the C2 ergometer other than trying a 2k or 500m or rarely a 20'/5k type piece. Never. Ever. I've been at gyms with C2s for five years now and guarantee you that anyone that isn't a rower (or in a Crossfit type program) on the erg is not getting health benefits from it.

It's easy to use a treadmill. You walk everywhere. Some people just don't want to put the effort into learning how to properly row. And you're not doing those people any good by giving the this extra silly option to make them 'feel' differently while they piddle about for 10 minutes.

For almost thirty years, the primary obstacle to users being able to experience and enjoy the full potential of the C2 ergometer, has been the primitive design of the handle. The user of the stock handle is restricted to one movement - and even that one movement is bio-mechanically flawed.

You are quite the headcase. You seem to think that the handle and only the handle is an issue. The issue is that MOST PEOPLE do not know how to use the machine. You, sir, do not know how to use the machine. What does a typical training session look like for you, out of sheer curiosity? If people could row with something close to proper technique, they would be able to "experience and enjoy the full potential of the C2 ergometer".

The handle makes the motion completely symmetric. That is the reason it is fixed. You need that symmetry when training (or just getting a workout in).

[johnlvs2run]

I've been at gyms with C2s for five years now and guarantee you that anyone that isn't a rower (or in a Crossfit type program) on the erg is not getting health benefits from it.

Heh, that is bull crap.

Anyone who uses a Concept2 rowing machine is a rower, so your assertion is ridiculous. Probably what you meant to say is anyone who does not row in a boat, where by convention you are taught to bog down between strokes, totally lose any sense of coordination or rhythm, and gain a blockheaded deportment.

That the world champion Danes and Italians row entirely differently does not seem to make any difference.

I personally learned to row like them, in my garage, before I ever found any information about others, except for the Concept2 instruction manuals, which I completely ignored to my benefit. Any fitness athlete can do likewise.

[Rockin Roland]

There would be so many occasions at gymnasiums where people jump on a C2 ergometer and thrash around for 5 minutes then get off and move onto another piece of exercise equipment.

One can debate for hours if these people can be actually classified as rowers while they were on the C2 erg for that time. You can take the argument even one step further and say that the movement to row on a static C2 erg has little correlation to what actually is required to row a boat on the water. But most gym users wouldn't be capable of comprehending such an argument.

So just let them feel proud and call themselves rowers regardless how aweful they may have looked on that C2 ergometer. The real truth will hit them hard one day if they ever decide to get into a rowing shell on the water.

And it won't matter how bio-mechanical the handle on their C2 erg was because it will do absolutelly nothing to prepare them for their experience on the water.

[johnlvs2run]

Every time I've been to the lake I've seen a few fat slobs rowing around on a boat for 5 minutes and half of them fell in the water.

That tells me all that I need to know about on the water rowers.

They all suck.

Except for the Danes and Italians, that row the way that I learned how to row on my own.

[Slidewinder]

Bloomp:
I make no claim to be a rowing athlete or any kind of athlete, but I do know a bent wrist when I see one, and a bent wrist under stress (as what occurs with the stock handle) is not good for anyone, athlete or non-athlete.
Your continuous harping about my technique grew tiresome quite awhile ago. Give it a break. I have already stated that I have spent far more time working on the C2 ergometer than working out on the C2 ergometer. My interest is mechanical design, and I know that the stock handle, as a human/machine interface, is a stone age implement compared to the Slidewinder handle.
Wake up! The stock handle is undeserving of your love. It's just a padded stick! It's not an amazing piece of technology, an engineering marvel, impossible to improve. After twenty-five years, I think it's time to reassess this love affair you are having with a padded stick.
Robert

[Tinus]

but I do know a bent wrist when I see one, and a bent wrist under stress (as what occurs with the stock handle) is not good for anyone, athlete or non-athlete.

Are you actually comparing to the old, small, stick handle or the newer and wider handle? While I still agree the wider one can still be improved the old smaller model has more clearly bad ergonomics.

A few days ago I took extra notice on the movement of my arms, wrist and hands on this old type of handle. I noticed the angle of my arms changing considerably in the transverse plane while my hands where fixed to the position of the handle which was awkward. I either have to bend the wrist and apply unnecessary torque or I have to bend my hand which decreases the quality of the grip on the handle and results in uneven (extra) load on the fingers.

On the newer,wider, model the angle of the lower arm changes less because the hands are positioned further away from the middle.

[Citroen]

Wake up! The stock handle is undeserving of your love. It's just a padded stick! It's not an amazing piece of technology, an engineering marvel, impossible to improve. After twenty-five years, I think it's time to reassess this love affair you are having with a padded stick.

How are you going to fit your funky handle in a boat? The ergo is a rowing simulator, it's meant to match the actions needed to row a boat on water as a replacement when the water is too cold or too frozen to get your boat out on it. It's often discussed that the ergo has a bunch of deficiences but if that's the case why do so many rowers use it for their winter training?

You've still never answered my question of what problem are you trying to solve because what ever it is you're not going to be able to solve the same problem when the rower moves from his ergo into his boat. Making a perfect handle doesn't wash because the motion of a sweep oar (and to some extent sculling blades) is adequately simulated by the current slightly angled padded plastic handle (no longer a padded stick).

Here in the UK we have a TV programme called Dragon's Den where folks just like you try to pursuade very wealthy folks to sponsor their invention. I'd love to see you appear on that when you won't even answer a simple question. It's the folks that can't answer their inquisitors on that programme who walk away with nothing more than their bus fare home.

[Slidewinder]

Tinus:
I agree that the new C2 handle is an improvement, but there is only so much that can be done with a rigid, single-piece handle. Since the width of the handle is fixed, the angular change of the arms as the stroke progresses is dependent on user arm length and shoulder width. Wrist angulation will therefore vary from user to user.
Some have told me that they use a light grip so that the flex of the fingers will accommodate the angular change of the arms as the stroke progresses, but this is adapting oneself to the deficiency of the handle.
With any well designed human/machine interface, the machine should adapt to the human, not the other way around.
With the prototype handle, bio-mechanical integrity is a given, regardless of the user's arm length or shoulder width. Referring to the still image of the handle I posted, and using a bit of visualization, it can be appreciated that as the stroke progresses, a consequence of the user's body mechanics is that the handle arms spread, keeping the handle arms and the user's arms aligned with the direction of applied force. The ergonomically correct "pistol grip" angle, referred to in a recent post, will be maintained throughout the entire stroke.
My emphasis in these posts has been the bio-mechanical superiority of the "Slidewinder" handle, but the design is not entirely about bio-mechanics. There is another desirable and fortuitous consequence of the just described spreading of the handle arms. Again, this takes a moderate amount of spacial visualization.
As the handle arms spread, there is an attendant angular progression of the handle handgrips in relation to the user's body. This angular progression closely replicates the angular progression of oar handgrips during actual sculling. I hope to make another short video to demonstrate this, since it is not at all clear in the first video that this is occurring. It needs a camera angle from the front and above.
So although comfort was a primary design consideration, the angular progression requirements for comfort and the angular progression requirements for a decent replication of sculling, happily coincide. I'm not comfortable blowing my own horn, but at present I have no choice. The Slidewinder handle is in another class entirely than either of the C2 stock handles.
Robert

[Slidewinder]

Citroen:
I have not concealed from you or anyone what my goals were in the development of the Slidewinder handle. Please read my May 6 post and the post immediately preceding this one. Read earlier posts as well.
In summary: the Slidewinder handle solves all of the bio-mechanical problems which have plagued C2 stock handles since the introduction of the Model A. It enables an improved replication of the sculling action (more on this in future posts). It enables a variety of rowing and non-rowing stroke geometries.

I'm not sure why the Slidewinder handle elicits anger in some people. Possibly it is something to do with having one's illusions shattered - that the beloved C2 ergometer is not perfect after all. I've written before that the C2 machine has almost reached the status of a holy icon, and therefore anyone who dares to criticize it is a viewed as a heretic. The prototype handle has been very well received in some quarters (eg: the Trent University rowing club) but I have also been subjected to verbal abuse (right here in this forum) which is completely unnecessary. If someone has an argument to make that the Slidewinder handle does not solve the problems and transcend the limitations of either of the C2 stock handles, then I am happy to hear that argument, but calling it silly, and strange, and ridiculous, or referring to me as "a head case" (as a recent poster did), is just name calling. Can we not aspire to a higher level of discourse?
Robert

[Citroen]

I'm not sure why the Slidewinder handle elicits anger in some people.

Not anger, simply futility.

[Slidewinder]

I'd like to clear up something I missed earlier in this thread.
I have in past posts pointed out the advantage of being able to rotate the handgrips when using the Slidewinder handle. That is:
- enables various rowing and non-rowing stroke geometries
- movement capability adds variety and interest to the exercise program
- rotation of the hands engages various muscle groups in different ways,
broadening the scope and appeal of the machine

One important point, and one of interest to rowers, was overlooked in the discussion pertaining specifically to hand rotation.

One poster vigorously dismissed this hand rotation capability. He wrote that this movement matches nothing that occurs during actual rowing. This is incorrect, but somehow this falsehood slipped past me.
There certainly is, in actual rowing, a hand rotation (an angular change) taking place in the same plane as enabled by the Slidewinder handle. It's not a dramatic rotation, but it's there.

As the rower places the blades of the oars in the water at the catch, and then raises them out of the water at the finish, the shafts of the oars pivot (rotate) in the oarlocks. This results in an angular change of the oar handgrips. This angular change of the handgrips during actual rowing can be exactly replicated when exercising using the Slidewinder handle.

Let's not waste more time laughing at the position of my hands in the video. Any experienced sculler, using the prototype handle, could and would exactly replicate the angular change of actual oar handgrips as the oars pivot up and down in the oarlocks and the blades dip in and out of the water.

Then of course, there is the simultaneous angular progression of oar handgrips in a second plane, caused not by a raising and lowering of the oars, but by the arc of the oars pivoting in the oarlocks from catch to finish. As explained in my May 9 reply to Tinus, the spreading of the handle arms of the Slidewinder handle as the stroke progresses is a natural consequence of the user's body mechanics, and this results in an attendant angular progression on the handgrips in the transverse plane, which closely replicates the angular progression of oar handgrips in that plane during actual sculling.

So, the Slidewinder handle enables an angular progression of the handgrips in two planes, replicating the angular progression in those two planes experienced during actual sculling. Adding angular progression in the third plane (ie: adding a twisting capability to the handgrip), to enable a virtual feathering of the oarblades, would be icing on the cake, and a simple thing to do.
Robert

[Slidewinder]

Citroen:
Please read the immediately preceding (May 11) post as well. Nothing is being concealed from you, everything is being explained, but you still must make the effort to comprehend.
Robert