Guru Sidero - steel road bike *Now on Sale*

So this is another Studio demo/floor bike. I decided to try out the new steel offering from Guru, and I must say, it turned out great.

I pieced the build kit together to match (as you can see) the bike's paint, and the result is striking, I think.

I order the demo bikes with my own Studio signature geometry -- basically I tweak the stock geometry provided by Guru so that it fits the cyclist(s) I think would be interested in such a bike.

Head tube = 14 cm
Effective Top Tube = 50 cm
Standover = ~73 cm


The bike is built with SRAM Force throughout, Ritchey Pro Alloy kit, and Fulcrum Racing 7 wheels.

The Fulcrum wheels were a nice addition. This year they changed the wheel from having red accents on the decals to the hubs, rims, and nipples all being fully anodized red. They really make the look of the whole bike.


I have again used the SRAM SuperLight bar tape -- this time in red -- it just has a great feel to it and it wears extremely well. I have two clients that I built bikes for a year ago. Just did a check-up on their rides and the tape still looks brand new; that is considering a lot of miles and a couple of trips overseas with the bikes.

This complete bike, for full custom geometry, is $3950 with a Force group and about $3300 with a SRAM Rival set up.

I think this is a really great pricepoint for a non-pricepoint bike.

What are our muscles really doing when we pedal?

So my fit Studio is in a  Physical Therapy clinic, which makes sense, because I am a practicing PT.  My co-worker, and owner of the PT clinic, Rik is trained in a new biofeedback system.  Biofeedback uses electrode patches placed over the muscles to determine how much these muscles are working -- how much, how soon they kick in, how long they stay "on", how they "turn off", etc.  As you can imagine, this is highly useful with our clients.

So we decided to test a few cyclists and see what we came up with.  We could simultaneously use the Retul, to pick up movement imbalances and then cross reference with the biofeedback to try and figure out what the muscles on each side of the body were and were not doing.  We can even then use the biofeedback while the person pedals to "train" them what activating certain muscles at specific times "feels" like to help correct the underlying muscular problem.

First we have to test as many people as we can, to start to figure out common muscular patterns.  Hopefully we can figure out what is "normal" but if my line of work has taught me anything, it's that there aren't many "normals" out there.  That's why I think it's more likely we'll find common motor patterns that may not be symmetric, amongst many athletes.

Subject #1 : Me, 33 y/o, male, 5'10", 175#

I have a fairly symmetrical pedal stroke.  If I had to guess I would think that I am a bit right side dominant, and probably scoot off the right side of my saddle because of it.  But we don't have to guess, because here is a right and left Retul file from a recent test on myself:

Not bad.

Next was to hook up the biofeedback.  This involves placing small sticker-like electrodes strategically over the muscles you want to test.  Wires snap to the electrodes and run to a little processing unit that reminds me of a car radar detector.

The "radar detector" talks to the laptop via a BlueTooth connection -- the setup is pretty slick.

The software that Rik uses seems to have endless choices on how to set up the display screens so that you can simultaneously see what the

 different muscle groups are doing.

  When I was hooked up to the biofeedback unit we decided to test vastus lateralis (VL) (the quadricep or thigh muscle on the outside of the

 leg -- this tends to be very pronounced in cyclists), vastus medialis (VM) (quad to the inside just above the knee, and the hamstring.  We tested these muscles on both legs, so we could compare how much more the right or the left lateral quad was working, but we could also compare how much and when the medial vs. the lateral quad did work on the same side.  We could also compare this to how the hamstrings worked.

We tested all three muscle group -- VL, VM, hamstring -- on both legs, of course at 150 watts and at 215 watts.

The printout from the biofeedback looks like this:

The lines and squiggles at the top half of the page are usually in color, but they are a bit above what we want to get into here. 

Below are the printouts bottom half of the page.  The colum to focus on is the one that says "Mean" -- they are basically the normalized mA that the electrodes pick up from each of the

 muscles.

There are four sets of data:  comparing VMO/VL at 150 Watts, VMO/VL at 215 watts, VMO/hamstring at 150 watts, and VMO/hamstring at 215 watts.

VM/VL @ 150 watts

VM/VL @ 215 watts

VM/hamstring @150 watts

VM/hamstring @ 215 watts

As you can see from the sheets, my right quads (medial and lateral) both work more than the left at all wattages.  But when I increased from 150 watts to 215 watts my left quads increased their activity 18% while the right increased 23% (VL) and 29% (VM).

The next round of tests, comparing the VM to the hamstrings on both sides confirmed an 18% and 29% increase respectively for left and right for the VM when going from 150 watts to 215 watts.  The hamstrings, which overall, were not very active increased 31% on the right and 38% on the left; this increase on the left might make one think that the left "evens out" at higher wattage, but I think it is still a bigger issue: the right hamstring was more active at 150 than the left was at 215.  The fact that the starting point for the left hamstring was so bad made it's improvement seem more drastic.

What did we learn?

I think this first round of tests is encouraging and shows that we can, with good effect correlate what our mechanics are like (from the Retul data) and what the muscles themselves are doing.  We should be able to explain why a cyclist may pedal with an asymmetry and whether it is due to a poor motor plan or if it has more structural origins.

I think we can safely say that one of the main reason that I sit a bit skewed on the saddle is because my pedal stroke's motor plan has a significant emphasis on my dominant right leg.  I think with more data we will see that my current pedal stroke is poor in the efficiency category because I have not been riding as much  lately and I am getting a very small contribution from the hamstring muscles.  I am not "pedaling ellipses" but rather more up and down (and definitely more down than up).

Theory

I have a theory as well about the activation of our quadriceps when we pedal that has to do with left and right efficiency.  I believe I am more coordinated (because pedaling is a coordinated task) on my right leg -- it's clear my hamstring are more active on the right and help to smooth out my pedal stroke.  I am also more skilled at one leg pedaling drills on my right leg -- less "clunking" through the stroke and better cadence.  

I think, based on some of the muscle activation graphs that I saw for me (and they would have been difficult to post here -- sorry), that our more efficient leg will see the quads activate later and relax earlier than the non-dominant side.  So the non-dominant side will have a more consistent or longer activation patter than the dominant side.  

This to me seemed counter-intuitive at first, but after some thought I realized that because my dominant side hamstring were activating better, they would inhibit the quads sooner since the load was now taken up by this new group of muscles -- the more "normal" or efficient pedal stroke.  The dominant side could more accurately and quickly kick itself on and off in time with my cadence and when it kicked on it could fire more motor units more quickly.  I think this would have implications, of course, on negative torque values (when your quads are still pushing down on the pedal after it has passed the dead bottom center position and therefore exerting negative torque or power) but also in terms of fatigue.  The non-dominant quad is staying "on" longer, even when it shouldn't and wastes unnecessary effort -- it fatigues quicker even though it is adding less to the overall workload.

Anyway, I should have more data coming this weekend and next week with a  few more guinea pigs so stay tuned.

uber-commuter

I had to post these pictures.  I don't haul this much normally, of course, but today I had to bring a number of things in to work.  This is why I love the Surly Big Dummy.

I had to get all of this onto my bike (well I could have driven, but that would be cheating):

And here is how I did it:

I love this bike

Talkin' bike seats

I mentioned in my last post that, for the average woman, and ideal seat design would be wide in the back to support the wider ischial tuberosities, but then needs to quickly narrow to avoid compressing the tissues distal and lateral to the sit bones. 

This narrower space between the femur and sit bones that we tend to rest (which ends up being the proximal hamstring -- medially the semi-membranosus and laterally the biceps femoris) is not the only reason for this saddle shape.  The woman's sit bones are oriented more in the frontal plane (more side to side) than a man's.  The male sit bones are set more in the sagittal plane (front to back).

When you factor in the natural translation of the hips and pelvis downward at the bottom of the pedal stroke, you can visualize that the male sit bones can more readily follow this path of movement -- sort of like a knife blade slicing through the dirt.  The female sit bones can't move as easily in this path -- imagine running the same knife through the dirt now turned to it's side a few degrees, like a plow.  The amount of shear force (or at least the potential for shearing) is much greater.

Essentially, all the angles of the pubic and ischial rami (the structures that form the "loops" on the bottom of the pelvis, and that we sit on) are steeper and sharper and because of this, less contact with saddles is probable.  I think this is the reason women often struggle with saddles -- more contact and shear forces -- and not just the fact that they have wider sit bones.

Saddle position

Of course, the right saddle is nothing without it being fit in the right position.  Many cyclists are on saddles they are unhappy with, but the reason is that they are not sitting on the part of the saddle that is meant to be sat on.  Most are scooted too far forward, even to the point where the sit bones don't rest on the saddle, but rather the saddle is squeezed in between them and the rider is resting more on their soft tissue -- this is a problem, obviously.  A huge mistake I see all too often is having the saddle tilted down --- yes, even a little is generally not a good thing.  

A bike seat needs to be in the right place fore and aft so that the sit bones can contact the wider, more cushioned portion of the saddle, and then it needs to be level so that the sit bones can rest on it.  If you aren't perched on your bike seat, then you aren't effectively stabilized to make full use of your pedal stroke. 

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Think about this: 

If you have a seat slid all the way back on the rails, so that the seatpost clamp is at the front of the seat, and it is level.  What happens when you sit on the saddle?  What if the rails are made of Steel?  Titanium?  What I'm getting at, is that a saddle has a static (or unweighted) position and a dynamic (weighted) position.  The dynamic position is the only one that really matters.  It has been my experience that especially with titanium railed seats if the seatpost clamp is to the back of the rails the seat will flex downward, if towards the front of the rails the seat will flex backward.  Therefore I have allowed some seats to leave my Studio tilted up or down at times to accommodate.

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This leveling of the seat brings me to my last point about a good seat -- for a man or a woman.  The seat should have at least some portion of it's surface should be flat and not fully sloping. 

This FSA saddle is a good example of when some seat designs can cause trouble for people.

The centerline of the seat is the high point and the cover slopes downward to either side.  I am sure there are people who find this saddle comfortable, but I haven't met them yet.

I am intrigued by the new fizik Antares -- the entire saddle looks flat.  I will have to try it out and get back to you on that one.

Next up :  Some top secret stuff going on in the lab.  Well, not really secret, but it should be pretty cool.  We are combining the use of the Retul dynamic "mo-cap" with a very sensitive biofeedback system so we can see what exactly some muscles are doing when we pedal, and using all the information (and there is tons!) to try to determine what the leg muscles are doing when....say, a knee tracks laterally more then the other side. 

From the preliminary findings, I think I can say that many will be surprised at what we are finding.

--J

"Influence of Gender, Power, and Hand Position on Pelvic Motion during Seated Cycling" Sauer et al 2007

Sauer, J.L., J.J. Potter, C.L. Weishaar, H.L. Ploeg, D.G. Thelen.  Influence of Gender, Power and Hand Position on Pelvic Motion during Seated Cycling.  Med. Sci. Sports Exerc., Vol. 39, No. 12, pp. 2204-2211, 2007.

This is the first installment in some interesting research I have been kicking around and using in my bike fitting practice.  I have decided to share a few bits here.

This first study took trained cyclists and they measured movement through the hips and pelvis at three different wattages (100 W, 150W, and 200 W), on three different saddles (Bontrager X-Lite 2006 mens, fizik Vitesse womens, and Bontrager Race Lite mens), and in two different hand positions (tops and drops).

It did not effectively determine much in the way of gender differences.  I think they set out to find out if riding on the drops versus the tops caused more pelvic motion for males or females.  Perhaps they were expecting more aberrant pelvic motion among females, I don't know.  Overall I think they tried to make their scope too broad -- they were trying to figure out too many things at once.  This, I think watered down their results a bit.

They fessed up to their short-comings in their Discussion, which is admirable but still doesn't help to improve the utility of the study.  The short-comings they listed had to do with the fact that the women were tested at the same wattage as the men and therefore at a higher percentage of their maximum - so asymmetries would be more pronounced in the women due to a greater relative workload.  

The women were also tested on the same handlebar (which had 145 mm of drop to it), and given that the women were smaller, they were forced to relatively lean further forward when they went in the drops.

One other thing I wish they had done, was to include more information and clear photos of the saddles they used -- it can be difficult to find saddles outside of their production year.  And saddles can be changed often from year to year, so finding a 2009 fizik Vitesse may not be very instructive.

Things I learned:

The women's ischial tuberosities (sit bones) were (on average) 134 mm apart center to center, while mens were 115 mm.  Nearly 2 cm difference in width of the sit bones -- that's significant.

What does this mean for bike fitting? Well, simply women's bike seats should be wider at the back of the saddle so their sit bones can rest on something properly, right?

Well, maybe.  Remember, these are averages -- some women have hips shaped like a 13 year old boy, so we need to think individualistically.  But also, this study found that the center to center distance between men's and women's hip sockets was NOT significantly different.  

This reinforces to me a long-held idea I look for in women's seats (as it applies to a woman who shares these "average" proportions -- remember, we need to take things on a case by case basis):  Yes, their seat should be wider toward the back to accommodate the wider ischial tuberosities, but it's my opinion that the saddle needs to narrow very quickly in the middle -- or as I call it, the transition --(essentially the part of the saddle below which the seatpost is clamped to the rails).  

To get a visual on the anatomy, check out this link for a view of the pelvis.  The bottom picture gives you a sense of where the femurs attach to the hip socket (acetabulum), so when you look at the male and the female structures above it, you can see there is a difference in how the femur relates to the ischial tuberosities.

Consider the fizik Arione saddles below.  The little hash marks along each side of the saddle are part of their "WingFlex" technology.  This is the transition area that I was referring to.  In the case of the Arione, this is very effective for some people -- mainly men over about 165 pounds seem to benefit.  Perhaps they are heavy enough to take advantage of the Wings and actually cause them to flex out of the way.  I have not found as many women that are comfortable on them.

I believe this is necessary because the gap between where their sit bones contact the seat and the path the femur takes during the pedal stroke is narrower, which can put more shear force on the soft tissue just distal and lateral to the ischial tuberosity.

I feel many women would do better -- and, again, this is a generalization -- on a saddle more like:

Well, not this exact saddle, but it's female equivalent.  Some of you may recognize it as a Selle SMP Stratos, and I think the fact that the saddle narrows down quickly (the angle of this picture does not do it justice) keeps the width where it is needed (in the back) and keeps material out of the way of those distal-lateral soft tissues by our sit  bones.  You can see the actual women's version of this saddle here.

Next post I'll talk about another reason that women's pelvic motions on the saddle differ from men's, since it can't be explained by hip joint or ischial tuberosity widths alone.

Cycling Research?

Unfortunately there is not as much science entrenched in the culture of cycling.  For years, Euro pros abstained from sex before races because it was feared that it would rob them of some essential power, for god's sake.  (Although Mario Cippolini worked hard to make us think he did not follow this logic.)  

Certainly this is changing, what with pro teams and amateurs alike making use of physiologic testing, wind-tunnels, and accurate power data.

The arena of bike fitting has had a few stabs at this, but many (like Specialized's BG Fit) are tainted by a corporate and retail driven focus.  

So I guess fads and marketing need to be treated with some apprehension.

In the realm of physical therapy and sports rehabilitation, certainly there are fads and marketing within the industry, but good therapists tend to use what works -- which is, most often, sound exercise regimens and manual treatment techniques -- not the Tony Little Gazelle, the Ab-Lounger, or that electrical stimulation belt for 6-pack abs.  

For this reason, I tend to default to good old published research, whenever I wish a fresh angle on some idea.  It's more work - information isn't already broken up into sound-bite worthy tidbits by some marketing department, it's not immune to corporate influence (many studies ARE funded by corporations with an angle to support), and some studies are just not set up very well, so they may or may not really tell us anything with any degree of certainty.  But that is why getting good information from them is more satisfying - because it does take a little work and you have to be discerning in your reading.

So as often as I can, I will share some of the more interesting things that are out there -- I think many will be surprised (I know I am constantly) at what some of the research shows.  Here's a taste:

Did you know that a study was done about 3 years ago looking at the most efficient crank length for trained cyclists?  They tested riders with crank lengths varying from 130mm up to 220mm, and found no significant difference for even some of the most extreme differences.  Granted the test was a very short and intense (I believe it may have been as brief as 3 or 4 minutes) but the fact that a cyclist could score anywhere close with 130mm cranks as they did with 200mm cranks, on any test, is amazing.  It certainly puts into perspective how futile the hand-wringing regarding 175 vs 172.5 cranks, that many cyclists do, may be. 

Custom Studio Build #1

This year I decided to try something new with my "demo" bike fleet.

Generally, manufacturers work with their retailers in the late summer and fall to plan what bikes and how many the retailer wants to have on the floor that year.  Most manufacturers (especially the big guys) require very large orders, and offer terms or a grace period before full payment of the inventory is due.  I am extremely fortunate to work with custom builders who understand intimately the needs of a Studio my size.  

My studio works on a different business plan then most (larger) shops.  I am not about selling a whole bunch of stock bikes -- in fact I don't really sell but a couple the entire year.  Almost all of the work I do is full custom, and as such, it doesn't pay to have 20 stock bikes laying around as inventory or demos.  

In past years, I have picked a couple of common sized bikes of varying "bling" between the builders i use and placed an order with a good parts build and one of the basic paint schemes.  This has served me well.  The bikes I order, represent the builders well (which is the point after all) they look great, and I can sell them pretty readily throughout the year.

This year I thought of really making each of my floor bikes unique.  Custom paint.  Better kit.  Better grouppo.  Better wheels.  I even steered away from the "stock" size that these builders provide for floor model bikes and customized the geometry in a way that I have found fits a wider range of individuals better -- especially in my market.

So with that in mind, here is what my first "Custom Studio Build" looks like:

Here is a breakdown:

• Custom sized Seven VII in "Cue Ball White" paint, bare carbon decals, and raspberry hibiscus accents.  Custom Seven 5E fork (rake matched for geometry, of course).
  
  
• SRAM Red group, except for Force substitutes in the brakes and the front derailleur.  Compact crank with an 11-26 Red cassette.
• Oval Concepts R910 Aergo road bar, matching Oval Concepts stem, and r900 carbon seat post
• DT Swiss Mon Chasseral 1450 wheels
• Alpha Q carbon water bottle cages

I can't say enough about the frame.  It is clean and precise.  Every bike I have ever gotten from the good folks at Seven has been flawless.  The paint is exacting, and it is 100% ready to build right out of the box -- I like that.

I am a big fan of the SRAM Red, but I have started doing the Force substitution  on the brakes, for a modest cost improvement, and no compromise on function, and the front derailleur --again for a modest cost reduction, and the fact that I think the Force front derailleur is a little snappier in it's shifting.  Possibly due to it's aluminum and steel rather than aluminum and titanium construction.  

Weight penalty for the derailleur?  1 oz.

The DT Swiss Mon Chasserals may be one of the best deals out there.  The wheels are light (1450g), strong, and have the most bomb-proof hubs in the world.  Included in the cost are padded wheel bags and DT Swiss' RWS skewers.  Best of all, they're assembled right here in Grand Junction, Colorado.

The Oval Concepts kit is a relatively new addition here at the Studio.  I like the ergonomics of the Aergo handlebar, and the strong feel of the stem.  The reverse bolts are a mild pain in the butt to get some wrenches on, so on-the-ride adjustments could be tedious.  Really the only thing I took issue with is the complete lack of instructions or torque settings.  I don't appear to be the only person to belly-ache about this, as I found a few fellow sufferers during a quick Google search.  If a bar manufacturer  REQUIRES the use of their stem to maintain the warranty on the ($365) bar (which Oval Concepts does) then torque settings (at least!) should be supplied.

The bike turned out great -- I couldn't be happier.  At a recent Open House, this bike garnered much "oohing" and "aahhing" in the gallery.  I don't think it is long for the sales floor.