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 Post subject: Re: Clipless merits
PostPosted: Fri Sep 06, 2013 2:23 pm 
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kingoffootball wrote:
My refusal to use SPDs is obviously hampering my climbing ability.

I can understand why people use them, but I'm happy with just grippy flat pedals and grippy soled shoes.

Apart from my aversion to being attached to the bike, I also like the ease of slightly adjusting your foot position, to allow for injuries, to help build strength in tendons/ligaments/muscles and to increase comfort over longer rides.

If the only reason for me to use them was to gain a little extra speed that wouldn't be enough to tempt me, as I'm so inefficient in other respects that gains would be a lot easier to find elsewhere, without attaching myself to the bike (better bike setup, better riding technique etc.) - and I'm not convince that being able to go a little bit quicker would add that much to my enjoyment.


It's not that I don't see value in clipless - clearly there is some - but often I think it's overplayed. Also, whilst toe-clips are out of vogue - and have been for some time, many of the main things clipless brings, can largely be claimed for toe-clips too.

The notion that being able to pull, as well, will transform your cycling, is mostly overblown. Sure, for brief periods there may be some value, in very high or near maximum effort (load, rather than cadence). Other than that, though - which is limited, let's not mistake that - choosing the right gear, the right cadence, and how well your cardiovascular system is performing tends to be a big factor in most of cycling.

Out-and-out leg power may have a bearing for starts, sprints, and brief periods when climbing, but effort is not efficiently used in that way, in some sustained fashion.


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 Post subject: Re: Clipless merits
PostPosted: Fri Sep 06, 2013 2:41 pm 
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mattr wrote:
JamesM wrote:
So explain to me why I can sustain higher speeds and higher average heart rates by pedaling in circles. Is it placebo maybe?
You've increased your pace and decreased your efficiency. Just training so you can push 5% harder would be more beneficial, and more efficient (probably a smaller heart rate increase). Pedaling FASTER would be the best way to do it. (But you still need to be able to press on)


How have I decreased my efficiency?

First you say just pushing 5% harder would be more beneficial. Remember we're after a 15% speed increase here so I'd guess with losses that's circa 25% power increase. So if i'm going to gain 25% more power by pushing 5% harder I need a big increase in efficiency as you said. But you also say the best way to do it is pedal faster. Do you know what cadence I currently ride at? It takes energy to spin my legs even when they have zero load at the cranks, surely spinning them faster would decrease my efficiency even if it did result in more power? Is that what you ment in your first comment? So assuming I actually need to pedal slower to increase efficiency, haven't I just lost quite a chunk of power (Power = Torque x RPM) and therefore wouldnt I need a fair bit more than a 5% increase in torque to gain my required 25% power increase. Further, why do I have to get that extra torque soley from my quads? Why cant I use other muscles in my legs too?

So many questions. :wink:


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 Post subject: Re: Clipless merits
PostPosted: Fri Sep 06, 2013 2:55 pm 
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Neil wrote:

Why are you convinced it's the same effort level?

Science says otherwise. When you're running, you tend to be doing so in strides, which are supporting, and propelling your bodyweight - plus, as well as propelling your body, not merely in one vector, you are also moving your arms.

On a bike you are merely spinning your legs. Yes, there's the additional weight of the bike, and there's other factors at play, there. Clearly a bike is less physical effort for much the same speeds as running, else we'd just run everywhere, and not cycle.


Of course the bike uses less effort for the same speed, but here we are talking about going as fast as you can sustain for say one hour. Max effort level that I can sustain for 1 hour always results in a heart rate delta between the cycle and the run of around 10bpm.

Are you saying that using extra muscles uses up the extra capacity?


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 Post subject: Re: Clipless merits
PostPosted: Fri Sep 06, 2013 3:03 pm 
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JamesM wrote:
Neil wrote:

Why are you convinced it's the same effort level?

Science says otherwise. When you're running, you tend to be doing so in strides, which are supporting, and propelling your bodyweight - plus, as well as propelling your body, not merely in one vector, you are also moving your arms.

On a bike you are merely spinning your legs. Yes, there's the additional weight of the bike, and there's other factors at play, there. Clearly a bike is less physical effort for much the same speeds as running, else we'd just run everywhere, and not cycle.


Of course the bike uses less effort for the same speed, but here we are talking about going as fast as you can sustain for say one hour. Max effort level that I can sustain for 1 hour always results in a heart rate delta between the cycle and the run of around 10bpm.

Are you saying that using extra muscles uses up the extra capacity?


I was kinda hoping what you actually described here, and the process you've been through in the discussion would be telling you something?

What is giving you the impression that involving additional muscles for a particular activity, is going to make it more efficient for your body to sustain?


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 Post subject: Re: Clipless merits
PostPosted: Fri Sep 06, 2013 3:17 pm 
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Neil wrote:
I was kinda hoping what you actually described here, and the process you've been through in the discussion would be telling you something?

What is giving you the impression that involving additional muscles for a particular activity, is going to make it more efficient for your body to sustain?


Nothing, although I've yet to see an explanation as to why it isnt!!!

The point I was trying to make is that two muscles can generate more power than one at a sustainable level. So you go faster and as long as you can make the distance you need to make you'll get there sooner and have a higher average speed. So what if you burn more calories, if you had enough in stored sugars in the first place then its all good.


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 Post subject: Re: Clipless merits
PostPosted: Fri Sep 06, 2013 3:24 pm 
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If you rode along with only one foot on the pedals how fast would you be able to go and would you be able to get your heart rate as high?


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 Post subject: Re: Clipless merits
PostPosted: Fri Sep 06, 2013 3:33 pm 
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kingoffootball wrote:
My refusal to use SPDs is obviously hampering my climbing ability.

I can understand why people use them, but I'm happy with just grippy flat pedals and grippy soled shoes.

Apart from my aversion to being attached to the bike, I also like the ease of slightly adjusting your foot position, to allow for injuries, to help build strength in tendons/ligaments/muscles and to increase comfort over longer rides.

If the only reason for me to use them was to gain a little extra speed that wouldn't be enough to tempt me, as I'm so inefficient in other respects that gains would be a lot easier to find elsewhere, without attaching myself to the bike (better bike setup, better riding technique etc.) - and I'm not convince that being able to go a little bit quicker would add that much to my enjoyment.


For you not having clips means you can jump off faster, lift the 35lb bike on your shoulder, run up the hill much quicker than we can ;-)

The main advantage after not getting bounced off my pedals for me is being able to rapidly drop the weight of the rear wheel or whole bike (I.e lift/jump thing) compared to not being unclipped. I can bunny hop without but it's so much easier to pop the rear wheel up, both at the same time using clips (for me spuds as I find them safer and less flexy than mt. zefal clips n straps)
This technique is quite valuable for me.

I couldn't give a toss about efficiency. Yes I do pull up, used to more and the muscles feel it. Quite nice over a long distance or up steep hills.


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 Post subject: Re: Clipless merits
PostPosted: Fri Sep 06, 2013 3:45 pm 
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Is anyone here a qualified sports scientist, with experience in cycling?
I feel there is much keyboard/ethusiasm speculation going on, with little hard, factual, evidence based research and conlcusion.

The way I see it is this*

Professional cyclists of all types use clips, and have done for years.
Professional cycling teams (club, pro and national) employ some very clever, technology based research and scientific boffs
Any pro will tell you the benefits of pulling as well as pressing
There must be something in it

*admittedly, this is a very lay opinion


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 Post subject: Re: Clipless merits
PostPosted: Fri Sep 06, 2013 4:05 pm 
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OK, let's go to the science and the studies, then...

*****
Int J Sports Med. 2008 Apr 17 [Epub ahead of print]
Related Articles
Click here to read
Effects of Pedal Type and Pull-Up Action during Cycling.

Mornieux G, Stapelfeldt B, Gollhofer A, Belli A.

Institut für Sport und Sportwissenschaft, Universität Freiburg, Freiburg, Germany.

The aim of this study was to determine the influence of different shoe-pedal interfaces and of an active pulling-up action during the upstroke phase on the pedalling technique. Eight elite cyclists (C) and seven non-cyclists (NC) performed three different bouts at 90 rev . min (-1) and 60 % of their maximal aerobic power. They pedalled with single pedals (PED), with clipless pedals (CLIP) and with a pedal force feedback (CLIPFBACK) where subjects were asked to pull up on the pedal during the upstroke. There was no significant difference for pedalling effectiveness, net mechanical efficiency (NE) and muscular activity between PED and CLIP. When compared to CLIP, CLIPFBACK resulted in a significant increase in pedalling effectiveness during upstroke (86 % for C and 57 % NC, respectively), as well as higher biceps femoris and tibialis anterior muscle activity (p < 0.001). However, NE was significantly reduced (p < 0.008) with 9 % and 3.3 % reduction for C and NC, respectively. Consequently, shoe-pedal interface (PED vs. CLIP) did not significantly influence cycling technique during submaximal exercise. However, an active pulling-up action on the pedal during upstroke increased the pedalling effectiveness, while reducing net mechanical efficiency.
*****

*****
Med Sci Sports Exerc. 2007 Jun;39(6):991-5.
Effect of pedaling technique on mechanical effectiveness and efficiency in cyclists.
Korff T, Romer LM, Mayhew I, Martin JC.

1Brunel University, Centre for Sports Medicine and Human Performance, Brunel University, Uxbridge, UNITED KINGDOM; and 2The University of Utah, College of Health, Salt Lake City, UT.

PURPOSE:: To optimize endurance cycling performance, it is important to maximize efficiency. Power-measuring cranks and force-sensing pedals can be used to determine the mechanical effectiveness of cycling. From both a coaching and basic science perspective, it is of interest if a mechanically effective pedaling technique leads to greater efficiency. Thus, the purpose of this study was to determine the effect of different pedaling techniques on mechanical effectiveness and gross efficiency during steady-state cycling. METHODS:: Eight male cyclists exercised on a cycle ergometer at 90 rpm and 200 W using four different pedaling techniques: preferred pedaling; pedaling in circles; emphasizing the pull during the upstroke; and emphasizing the push during the downstroke. Each exercise bout lasted 6 min and was interspersed with 6 min of passive rest. We obtained mechanical effectiveness and gross efficiency using pedal-reaction forces and respiratory measures, respectively. RESULTS:: When the participants were instructed to pull on the pedal during the upstroke, mechanical effectiveness was greater (index of force effectiveness = 62.4 +/- 9.8%) and gross efficiency was lower (gross efficiency = 19.0 +/- 0.7%) compared with the other pedaling conditions (index of force effectiveness = 48.2 +/- 5.1% and gross efficiency = 20.2 +/- 0.6%; means and standard deviations collapsed across preferred, circling, and pushing conditions). Mechanical effectiveness and gross efficiency during the circling and pushing conditions did not differ significantly from the preferred pedaling condition. CONCLUSIONS:: Mechanical effectiveness is not indicative of gross efficiency across pedaling techniques. These results thereby provide coaches and athletes with useful information for interpreting measures of mechanical effectiveness.
*****

Which tells us what we already discussed - pulling as well as pushing with the pedals, may make the pedalling most effective (ie, you may be able to deliver power maximally), but it reduces efficiency - which is why it doesn't significantly factor in anything other than brief periods of maximum effort.

Happy now?


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 Post subject: Re: Clipless merits
PostPosted: Fri Sep 06, 2013 4:12 pm 
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Neil wrote:

Happy now?



No Neil, I am not Happy... but only because you obviously have far more free time on your hands then I do :wink:

G


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