Are aero bars really

Triathlon Forum
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leverage bars.

In the thread on water bottle aerodynamics at the end I was somewhat lambasted for suggesting that it might be a benefit to manipulate aerobar postion to improve aerodynamics and was taken to task that such would eliminate the leverage effect of the present position and have a disastrous effect on power. I received no support for my view and it has been bothering me.

Is there any evidence to support this position? The only time I see good riders grasping the bars for “leverage” seems to be when they are stuggling, not when they are in a sustained power mode, when, it seems to me, having a relaxed upper body would seem to be an advantage. In addition, during TDF breakaways, riders now seem to try to “mimic” the aerobar position where I see no “leverage” advantage as no bars are present. What have I missed here?

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Frank, I thought your idea was interesting. However, if by “leverage” you mean “pulling” against the bars, I definately leverage the bars, especially while climbing (in the seat, high cadence climbing). I guess I’m not really sure how to describe the mechanics and I’m not sure if moving the bars up or down I would notice a loss of this power but it is definately something I do. I think in general, aero and power are compromises on a bike and what works for one may not work for another. One example, I know a biker (class two road racer) who happens to be a great cyclist (not a triathelete) but he is not the most aero with his positioning. He has worked with bike fitters to get more aero but the loss of power from the more aero position is more than he can make up in being more aero. In other words, the power he generates in his less aero posiiton more than makes up for the increased drag. Just my .02. Good luck this summer.

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Yes, I think TT bars are, in part, leverage bars. Lemond isn’t the only top level pro to make comments like the one Dan alluded to in the earlier thread. Lance has made several statements about how hard he works his bars over, and how hard it has been for him to find a stiff enough TT bar.

Isn’t it also interesting how often we see broken TT bars in the major tours? We certainly don’t see this with road bars, and for the most part, the broken bars seem to be the same thing that the rest of us use. I think if you were to measure the force exerted on TT bars AT THIS LEVEL, the results would surprise you.

Cobb has often alluded to the wattage differential in different TT setups, and the leverage point for the elbow seems to be a major factor. I think that a big part of the reason why some incredibly strong, powerful TT riders like Ullrich ride hands down is related to this. It’s also interesting to note that almost all of the hands down riders seem to ride with horizontal rather than vertical hand position. Is there a relationship here? Also interesting to note, as Dan pointed out to me, having the elbows higher than the hands has the effect of raising the perceived/effective bar height relative to the rest of the body, especially the shoulders.

Also, and very important, please note that the efforts required in a TT are dramatically different from those in a Tri bike leg. A tt is all about max power, leave it all on the road, draw every last watt out of your body, from wherever you can get it. A triathlete is looking to expend as little energy as possible while still riding fast - save some for the run. PLUS the Triathlete’s upper body is blown by the time they get on the bike. There probably isn’t much upper body strength left to help on the bike.

All that said, My biggest issue with your idea of raising the arms to “fair” the upper body is that I don’t think it will do what you suggest, or it will do it at the expense of the potential fairing effect the lower position supplies for the important lower torso to knees area. My reading of the latest wind tunnel info seems to strongly suggest that fairing around this turbulent may be of proportionally large benefit, and I would suggest that this is a big part of why the bar-mount water bottle tested so well in this study. If you look at how these bottles mount, they extend below the bars, down into the area I am talking about, and extend the fairing effect of the bars/hands well down onto the legs. I think anything that works to create a smoother airflow here is probably worthwhile, and especially if the rider has a close to the T.Tube pedalling style, you may be able to see very big gains.

But hey - that’s just a theory, and I don’t have any tunnel time booked.

MH

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I can accept the fact that one might leverage the bar for power when climbing. But, climbing is such a small part of the typical time trial or triathlon and the potential aerodynamic differences we are talking about are so great (4lbs vs 7.5 lbs - I would have never predicted they were even close to this large until Dan threw out those numbers) I wonder why someone would give up a couple of miles an hour for the majority of the race so they can climb a little better for a small portion of it. Doesn’t seem to make any sense to me.

I agree, that bike speed is trying to achieve the best combination of aero and power but this must be for the entirety of the race, not for one small portion. That is why I am so taken aback by this argument against changing position to improve aerodynamics.

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I would like to see some evidence that “working” the bars makes someone faster. With what technique does one work the bar for best effect? Does bar working technique change between the flats and hills? I have never seen a thread here on proper or best bar working technique to maximize power? Why not if it is so important?

I don’t know why people ride the way they do? Before LeMond was the first to use aero bars all the professional cyclists thought they were a gimmick. If he had not beaten Fignon in that time trial they might still think that. Just because someone is an “authority” doesn’t mean their pronouncements are correct. How long did it take the Vatican to accept that the earth is not the center of the Universe?

In cycling people tend to do a lot of what we do simply because we play copy-cat to whomever is winning, not because we put much thought into things. Maybe the guy is winning simply because he trains harder or has better genes, or takes drugs, and not because of his position or equipment is inherently superior. those who are less gifted must look to other ways to gain an advantage. Being smarter is one way.

And, BTW, it was Dan who said that raising the arms reduced the drag from 7 to 4.5 lbs. in the wind tunnel so your concerns about the potential “bad” effects of such seem ungrounded. I had just proposed that I thought it would be beneficial based on my musings which seemed to be confirmed by the watter bottle tests. The numbers Dan threw out blew me away.

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The point is, it’s not just when climbing. Road TT riders, especially the powerhouses, especially at this level, work the bars really hard on the flats as well. Lance, for example, puts out in the neighborhood of 450 watts continuous power in a 40k TT (or so I seem to recall), and if you look at his upper body, he’s working it the whole time. The really good TT riders are pretty quiet on the bike, but almost all of them still have a perceptible pumping motion going on - the upper body goes up and down or side to side in synch with the pedal strokes. Look at the arms of these guys when they finish - they’re pumped; they look like they just topped out on a 5.13

I’m not the world’s greatest TT rider, but I am a Cat 1, and after a 40ktt my whole body is spent, including my arms. After a TTT, I can barely move.

The last TTT I did, the parts that hurt the worst were my arms and shoulders. I think this was because I was the 138# guy sitting behind the 200# guy and the 175# guy, and I had to give it EVERYTHING to keep up with my pulls. Probably the best TT I ever rode. At the top level, every TT is like that.

MH

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so, what is the technique or does it just happen?

How much power would you lose if you just “rested” your arms in the supports and didn’t grip the bars?

I look at these guys and those upper bodies look pretty relaxed to me. If they were pumping those levers I would expect to be able to see the arm muscles working. They look pretty quiet to me most of the time.

If you are pumping those levers but not getting much power from same you could be wasting energy and if you were to quiet your upper body you might then have more cardiac output available to your legs for power output. the fact that you come in from these efforts wasted doesn’t mean you expended your energy optimally.

I would like to see some data that supports this supposition. I don’t think it exists. In fact, I would be surprised if anyone has ever looked at this.

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the best reason I’ve heard for working/pulling/whatever the aerobars for more power went something like “you can’t fire a cannon from a canoe…” Having the bars level or tilted downward makes for a much better “anchor.”
.

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I am familiar with the test Dan referred to, but I think that newer work supports my conclusions RE: bar placement. Also, please note, that the one absolutely constant result of wind tunnel work is that morphology plays a huge role in the aero-ness of a given position. As Gerard pointed out, he has seen a rider test higher with hands below elbows, but that doesn’t mean it will work for everyone. Anyone who is looking for absolutes in this field is going to find only disappointment.
Ultimately, as the body of work on aero bike positions matures, I believe that we will see a range of recommended positions, grouped by body type/proportions - and even that will be at best an approximation of good position.

I don’t know why people ride the way they do? Before LeMond was the first to use aero bars all the professional cyclists thought they were a gimmick. If he had not beaten Fignon in that time trial they might still think that. Just because someone is an “authority” doesn’t mean their pronouncements are correct. How long did it take the Vatican to accept that the earth is not the center of the Universe?

Uhhmmm… what exactly are you talking about here?

And Frank, might I suggest that you not ever criticize the validity of purely empirical evidence? I can’t count the number of times I have seen you defend just such reasoning in PC discussions.

MH

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I accept that the bars could offer some support for the recoil of pushing back at the bottom of the stroke and pulling forward at the top, if people are doing that to any degree, but not for pushing down or pulling up as the saddle supports one way and gravity supports the other. However, these forces should generally balance one another, since the two legs are always doing the opposite thing, such that the amount of force required to hold the body still should be small.

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I saw John Frey set the current US 40k time of 47 minutes and change on a bike that had no cow horn bars at all (he did this way back). All it had was aero bars with a single brake and a single bar end shifter. He had some trouble at the turn around. He was completely relaxed in the upper body until the final mile or so when he started to rock back and forth some. It had the old scott areo bars and were placed so they were horizontal. 24 in front wheel. The bike was a custom steel frame made by a local frame builder here in NM. The one reason we need the cow horns is so we can steer the bike. No other real reason as far as I can tell. He did not need the cause the course was Moriarty, NM 40k course. dead flat, dead straight.

Yuck

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MH wrote: “And Frank, might I suggest that you not ever criticize the validity of purely empirical evidence?”

What evidence? Claiming to do something is not evidence that it is actually done or or evidence that it is actually effective.

Most people believe they pedal in circles. Why, because people tell them they should, they think they should, they try to and they have no evidence they don’t. Unfortunately, almost all of them don’t do it and, now, the evidence is pretty easy to come by. Some choose not to change (their pedaling style or their opinion of their pedaling style), others do based upon less than perfect evidence as to what the benefits are or might be.

i do agree with you though, anyone looking for absolutes in this sport (or any sport) is going to be disappointed. It is why they run the races.

Frank

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I accept that the bars could offer some support for the recoil of pushing back at the bottom of the stroke and pulling forward at the top, if people are doing that to any degree, but not for pushing down or pulling up as the saddle supports one way and gravity supports the other.

I think that’s exactly what wer’re talking about here, but the question of degree may be open/variable.

It also may be that the more forward and low a rider’s position gets, the more the physics and ergonomics of that rider become akin to a forward recumbent. The superman position of Obree is probably the ultimate expression of this. It is readily apparent, on even a cursory examination, that the upper body/arms play a supportive/oppositional role (vs. the pedalling motion) when riding this position. If you rotate the riders position forward enough, at a certain point the arms are in fact providing the oppositional forces that gravity plays in a traditional position. When exactly, does this begin to happen? I don’t know, but it would be interesting information to have, and may well have bearing on this discussion. I wouldn’t dismiss it out of hand as a small contributing factor to overall power production in a TT position - and at the level of a tour rider, even an infinitessimal degree of improvement is noticeable.

MH

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One could “easily” put some strain gages in the aero pads and bars to measure these forces to see how much is actually be done. One cannot look at simply the forces on the bars by the hands as there may be opposing forces on the pads or saddle caanceling that exertion out. It could be like a facial grimmace. something someone does when they are straining to make them “work harder” but that actually has little overall speed effect. If there is a contribution, I expect it to be quite small, but I might be wrong. It would be nice to see some data.

There you go again Mike P. another study for you.

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Frank, First of all, I’m sorry if that felt like a lambasting. I simply meant to counterpoint your point. I have a strong way with words and expressing myself sometimes.

Now, as for the leverage thing. The leverage is not necessarily provided by “working” the bars, ala a good standing climbing push/pull technique. The leverage is useful in anchoring the upper body so that the legs have a stable platform to work against. There is a lot of torque induced from hips upward by powerful pedaling. This torque is anchored against at the saddle and aero bars. Most (but certainly not all; Botero would be an obvious exception) proficient TTers have a quiet upper body movement despite these huge torque forces. They are indeed working their entire upper body in providing that quiet stability. Just because there is no perceived movement doesn’t mean there is no work being done. We don’t often think about that aspect, probably because we are focused on the pain in our legs and lungs. Incidently that is a good reason not to neglect core body exercises, but thats another discussion.

You asked why we don’t use aero bars for climbing if they provide leverage. Well, it is a different event that allows for different techniques and leverage points in producing the power. First of all, climbing is much slower than flat TT, negating most aero advantage. That being the case, assuming a normal position vs more closed hip angle aero position is now an option. Power dominates the climbing equation. So we can be more upright, or even stand, something you want to minimize while TT’ing. In climbing we not only stabilize against the torque, but can assist it while standing by pulling/pushing on the hoods or drops. We are able to produce far more power gains than any loss of aero is costing us at those speeds. Conversely, TTing on the flats requires significant attention to aero, slightly more closed hip angle, slightly more back extension. We now need a better anchor for the upper body. Aero bars provide that vs. standard road bars or cowhorns. But you can still improve that anchor point by optimizing your position.

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Frank,

I certainly believe that one of the primary benefits of aero bars is the additional point of leverage they provide. And it’s not just pushing through the bottom and pulling over the top where it helps. To me its biggest benefit is in the main down . Try this: sitting at your desk, hold your hands like you would your bars, place them agsinst the underside of your desktop and pull up as hard as you can. Now do the same thing, but this time brace your elbows against the arms of your chair (yeah, I’m assuming they’re there). When I do this, I can pull up much harder with my elbows braced. This means I’m pushing my body down much harder too. To me this is very similar to what happens on the bike. It’s really the argument that perfection keeps making. I believe he is focusing on maximum power on the downstroke, through this sort of leverage. But it’s kind of a trade off. I don’t believe one could use this technique and pedaling in circles at the same time effectively.

You posed the question earlier that if this is so effective, why don’t riders prefer this position for big climbs to maximize power. Well, for a couple reasons I think. In climbing, aerodynamics is not an issue. (TTers worry about both aerodynamics and power) And (I’ll probably get destroyed for this) climbing isn’t about maintaining peak power for as long as possible. Finally, this position is totally illegal in all stages but TTs.

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It is ok I don’t feel lambasted. I can also be misinterpreted in my remarks when I question people. You wrote: " Conversely, TTing on the flats requires significant attention to aero, slightly more closed hip angle, slightly more back extension. We now need a better anchor for the upper body. Aero bars provide that vs. standard road bars or cowhorns. But you can still improve that anchor point by optimizing your position. "

This gets me back to my original idea. If aero is so important in TT why is the demonstrated ability to reduce drag from 7.5 lbs to 4.5 lbs being dismissed so casually? It is as if all those who thought it necessary to spend $1,000 to get aerodynamic wheels no longer think aerodynamics important.

Regarding anchor points, if we assume those riders with different styles (quiet body position vs working upper bodies) are developing similar degress of power if they are going about the same speed then the necessary anchoring must be being done using different techniques. One way to anchor is to leverage gravity combined with the simple position on the bicycle and a smooth pedal stroke which is probably the technique of those with the quiet upper bodies. This technique would seem to be more efficient to me as it does not require a lot of forceful “extraneous” muscular contraction to maintain position. Those who have not mastered this technique may need to use other muscles to maintain good riding position when exerting maximum power. However, I don’t see it as “necessary” to riding with power, or, even, desirable.

I was being a little facitious regarding the climbing as it seemed the claim was leveraging the bars added so much power that improving aerodynamics is a secondary consideration.

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“This gets me back to my original idea. If aero is so important in TT why is the demonstrated ability to reduce drag from 7.5 lbs to 4.5 lbs being dismissed so casually? It is as if all those who thought it necessary to spend $1,000 to get aerodynamic wheels no longer think aerodynamics important”

This is where the conflict begins. This is the point where power and aero have to be balanced against each other. I happen to think that the losses outweigh the gains in your proposed solution. I also happen to think that a reduction in drag on the order of 4.5 from 7 is unrealistic for the majority of riders given the only variable change being tilting the aero bars radically upward. I think the change would be less than 1 for most riders. At any rate it is all a balancing act to produce the best performance for each rider.

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the issue isn’t how hard can you push against the pedals but how hard can you push against them 6000 times or so in an hour. For most people we are talking less than 40 lbs peak force (let alone average force), something that doesn’t require a great deal of leverage to do well. Even using the extreme example of over coming 7.5 lbs force at 30 mph headwinds, only requires 60 lbf (on average) on the down stroke at 90 rpm and 7 inch cranks. At 20 mph the calculated average downward force on the pedal would only be 17 lbf.

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TBG writes: " I also happen to think that a reduction in drag on the order of 4.5 from 7 is unrealistic for the majority of riders given the only variable change being tilting the aero bars radically upward."

You may think it unrealistic (and I would have thought so also two days ago) but it just so happens that those were the numbers Dan reported coming out of the wind tunnel. I didn’t make them up. I haven’t been able to get any description of any set up change other than raising the arms way up. Maybe there was more.