SS analysis: strength or power?

Pure single speeders are a passionate bunch.  After doing a bit of  lurking on the mtbr SS forum and observing the SS related comments here it's obvious the top reasons SSers do what they do come from the heart.  As it should be.

Perhaps I will find that happy SS nirvana in time, but right now I'm a geared rider having fun on a SS.  It's my analytical nature that has me analyzing the demands of SS right now so that I can make a better plan to train for a SS event or two (or three or...  ;).  Nirvana is directly proportional to speed, 'tis a proven fact - so this quest is worthwhile.

There are two obvious paths to go when considering how to train for SS:  target specific aspects of SSing (on the road or MTB), or just go ride your SS.  On the geary, my long-standing paradox has been that to really improve, I have to do specific work - intervals and the like - usually on the road but not always.  So, I'm going to choose the former cause it's worked best for me in the past.  SSing 6 days/week might not be sustainable for me, it's hard stuff!

So then, what are the aspects of SSing that need special attention?  Power Tap to the rescue....the first step is to install the PT on the SS, go ride, then take a look at the ride data through the various tools available.  The most valuable of these has been Quadrant Analysis developed by Andrew Coggan.  Chances are that if you train with power you know the good Doc.

QA simplified:  every data point in a file represents a power output and cadence.  Knowing this in addition to the crank length the data is further broken down to the constituents of power - pedal speed (CPV) and average effective pedal force (AEPF).  In lay terms, how hard you are pushing on the pedals and how fast your feet are moving.  Crosshairs are then drawn with the intersection at the pedal force and cadence that represent what is  normally done at threshold power.  This divides the plot into 4 quadrants with these relative characteristics.

  • I:  high power, high cadence
  • II:  high power, low cadence
  • III: low power, low cadence
  • IV: low power, high cadence

Obviously, SS requires one to push darn hard at low cadences and really fast when spun out.  But where are the limits?  And are they trainable??  Key questions in my quest.  I'll be sharing my random thoughts along the way of this process.  They evolve daily ;)  But first, let's look at that QA plot again and see what it can tell us.  Note:  57 is not my preferred cadence so the QA crosshairs are misaligned in this plot...preferred cadence is about 96 so just about all points are in QII in reality.

There is a lot going on here.  Yea, it'd make a nice tattoo M but I'm not sure I have the bicep to pull it off so I'll stick to the geeky stuff ;)  The points here are from two different rides, one on a 32x18, the other on a 32x16.  The route is rolling, some steep short climbs, some fast descents.  Overgeared and undergeard, like every SS ride I've done.  The pace was moderate (not hard), but where it tilt's up I went hard enough so as not to walk.  IOW, L6 power levels. 

There is also some test data from 2 types of efforts:  maximal standing starts, one set is done seated, the other done standing.  It turns out the maximal AEPF-CPV relationship is linear, so getting some good points along this line allows one to extrapolate the maximal curve out to max force and max pedal speed.  That's what the 2 straight lines represent.  Those lines are the highest pedal forces I can achieve for any given pedal speed - I wanted to establish these lines to see how close SS low cadence stuff came to maximal. 

That's enough background.  Here are some things I see:

  • normal cadence range for SSing is 45-130.
  • typical pedal forces go up 550 N.  In geared riding they rarely go over 275 N (I'll post a comparison geared QA at some point) and for the most part are below 225!
  • pedal forces occasionally bump right up against that maximal force/cadence line 
  • pedal forces routinely go to (and above) 75% of max AEPF in a moderately paced SS ride.  This is in comparison to ~ 25-30% in a geared ride.
  • the ability to put out power at low and high cadences are equally important (but have very different demands!)

Finally, note the 3 iso-power curves - red, yellow, and orange.  In particular, note how they tilt rapidly upward on the left side.  Where they are  horizontal on the right, small changes in pedal force have big effects on power output.  But on the left, it takes huge changes in pedal force to alter power output, or from another angle, at very low cadences it takes huge AEPF to put out any sort of power.  In theory, at a cadence of 20ish I can do no better than threshold power no matter how hard I try.  So for anyone, no matter how "strong" you are, being overgeared beyond some point is going to reduce your power on the climbs.  Physics in action.

Did I miss anything?  Requirements of the soul perhaps??  They don't show up in QA ;)

This weekend I'll be doing some longer rides with the SS.  I'm curious to see what those data sets will say about sustainability of these higher pedal forces over the long haul.

Happy Thanksgiving!  Stuff yourself silly as is our custom...gives cyclists a reason to ride more.

 

Published Thursday, November 22, 2007 6:30 AM by Dave

Comments

# @ Thursday, November 22, 2007 10:10 AM

I'm going for a hike.

Ed

edemtbs

# @ Thursday, November 22, 2007 2:09 PM

Interesting. Trying to get a hold of what it all means!

First of all, did you do Stucki as an out and back? From the lower Bearclaw trailhead? I could clear all those climbs on a 32:18 two years ago, so I think that gearing would be a bit soft for ya!

So, we want to hit that sweet spot that'll keep cadences somewhat high on the steeps without spinning out too much on the flats? Simple!

And, what does this say about crank length (if anything)?

I still maintain that hiking prowess is key.

ionsmuse

# @ Friday, November 23, 2007 9:19 AM

I do think Ion is bringing up a very valid point =)


nice to see you have more things to greek out on Dave!

SlowerThenSnot

# @ Friday, November 23, 2007 10:17 AM

I'm done with my hike.

I'm curious if pulling up on the handlebars translates into higher effective pedal forces because I definitely use my back, shoulders, overall core and arms more on a ss, especially on hard standing climbs? In fact the correct upper-back power movement on my part allows me to clear some really hard stuff. SS'ing definitely exercises more body parts than just your legs.

So at your 96 preferred cadence the QA crosshair would be just to the right of 1.5? There's an interesting "blob" between there and 2.0.

What is a normal geared cadence range?

And I find bullet #2 fascinating. Why with gears is it so easy to "give up" and not pedal as hard? Is that really the case and if so doesn't that mean a lot of what we end up doing is a result of our mindset - on a ss you have no choice and so you just do it, on a geared bike you perceive effort and downshift? And wouldn't it also point to good power training but also possible over-training issues?

Ouch, I need another hike.

Ed

edemtbs

# @ Friday, November 23, 2007 9:39 PM

Dave N: Which point are you referring to? I count 5 from DC.

DC: I rode up from Santa Clara. Still part of Bear Claw but not ridden as much - as far is it gets from the south end. Climbs are punchy in the last bit but for sure the 2:1 gearing was faster. I'm experimenting ya know ;)

The crank length issue is pretty complex. At face value, increasing the crank length will decrease pedal force requirements for a given power and cadence, and would also make higher cadences slightly more difficult, effictively reducing max attainable cadence. Whole nuther can o worms and great question.

Hiking prowess - I saw you mentioned that on MTBR and it struck a cord. I'm totally in agreement with you on that one!

Ed: Good hike?

Getting out of the saddle absolutely raises pedal force. Note the blue and purple lines in the plot - the purple, higher line comes from standing (out of the saddle) tests. The blue was seated.

The blob between 1.5 and 2.0 is pretty close to my preferred cadence as you guessed. This data was just for a climbing part of the course which meant I was doing low cadence, higher powered efforts or easier higher cadence efforts. The blue blob comes from the latter.

Preferred cadence is highly individual. For myself it's quite narrow at 85ish on climbs to 105 on flats. This implies I prefer very low pedal forces...a major reason I am single speeding now cause high force low cadence is not natural to me. It's getting there though.

The combination of physics and physiology seems to have preferred cadences in the 70-100 range, even though 60 is supposed to be most economical. So I wouldn't think that using gears is "giving up", it's more about finding that optimal mix of force and cadence, the one that allows you to keep going. Whenever I get tangled up with SSers in races it's a big yo-yo affair. They hammer up climbs, spin easy on flats to recover (and appear to go backwards at that point), repeat. SSers have no choice but to hammer uphill unless they like hiking, no?

The human body is incredible in it's ability to adapt to stress. Stress it in specific ways, and it will get stronger at doing that task. Along those lines, SS requires tons of efforts above threshold power, and at the same time produces a ton of time not pedalling. Lots of intensity, lots of rest. My files are averaging about 45% coasting! Maybe I'm just a slacker?

I'm still collecting data and riding my SS into the ground ;) And I'm going completely public with it all cause y'all can help me learn a thing or 3 if you're willing and if it helps me learn things new to everyone we all win.

I really appreciate your comments/input!

Dave

# @ Saturday, November 24, 2007 6:54 AM

Dave, it's gonna be interesting to watch your programme evolve, even though all those abbreviations and crosshair blue squares confuse the shit out of me. Pesonally, I recommend a road fixy if you're looking to 'train' for ss'ing, simple as that.

tomi

# @ Saturday, November 24, 2007 3:00 PM

Re crank length: I've spent quite a bit of time riding both 175s and 165s on the SS. Did the Rim Ride and Kokopelli on 175s, Crested Butte on 165s. Same gearing.

When settling into a certain cadence, the longer cranks felt better, which translated into more power on long and steady climbs. The shorter cranks spun up faster, and were both easier to turn over on punchy and very steep pitches, and easier to spin real fast on the flats.

In the end, it's a toss up unless you geeked out and switched cranks for a given course. I've got the 165s on now, as they better suit the riding I pick the SS for these days.

ionsmuse

# @ Sunday, November 25, 2007 1:39 PM

opps not clear nuff...

I was agreeing with ion's point of hiking the bike...

walking speed esp... on muti-day rides is key when you only got one gear...

prob spent at least an hour per day on the GDR hiking just cause it was a nice change or to steep... or jacked my heart rate, made me sweat too much ect...

the dots and lines are interesting for sure...

I agree with Ed in terms of using the whole body with ss'ing. I've also wondered if ss'ing helps with bone dense.. and other things like that.

Good stuff!

SlowerThenSnot

# @ Tuesday, November 27, 2007 3:16 PM

Hey Dave interesting stuff. I loved your 26 vs 29 tests - they actually swayed me from a 29er. Any chance of doing a 650B comparison (just kidding).

I train and race both geared and SS, so I'll be following this closely for tips.

Not sure if you remember, but we met at the TR in 2006 - had an RV beside you guys. You gave me some hardboiled eggs when I was stuck in the food line one morning - thanks,

Iain

Iain

# @ Tuesday, December 04, 2007 9:20 AM

Awesome Dave!

This tickles the pseudoengineer gearhead side of my mind, and the physiology side of the mind.

Just stumbled on this after riding to work thinking about Carrol Smith's axion that is is better to make torque at high RPM since you can take advantage of gearing that way.

I SS because fundamentally I am lazy, and if I don't, I will get out of shape quickly for the more strenuous rides I like to do with gears. It absolutely helps my power which is essential in mountain biking.

I like Ion's comment about hiking. He is a tremendous hiker:). I hate getting off the bike so I die rather than do it. Okay for a recreationalist, but not good for the types of long rides you guys do.

Enel