Body position vs bar height – part 1

July 29, 2011

The information below we also share with our pro riders, to combat the misconception that lower handlebars are “better”. The basics:

  1. The riders’ bodies have “built in” angles at which they can perform the best. So when a rider is at maximum effort, the body will put the body in the position most suited for that effort. In particular this pertains to the hip angle as it is the angle between legs and torso that determines mostly how the power is generated. Note: I am not talking here about increasing power by changing body angles, the power a rider can deliver is pretty much determined by his ability to transport oxygen and flush out lactic acid, but to generate that power (whatever level that is), the body will want to put itself into its optimal position, i.e. its optimal hip angle in order to best use the muscles best suited for the effort.
  2. This means that with the bottom bracket and saddle fixed, when the body assumes its optimal hip angle, the back position is also determined. There simply is a position for the back at which the body is best capable of giving maximum performance, because it is the back position at which its angle with the legs are such that the optimal hip angle is achieved.
  3. Hence, changing the handlebar height does not really change the back position, at least not during serious exertion. Therefore, with the back position more or less fixed, a change in handlebar position means a change in arm stretch/reach/angles. With the back more or less fixed, meaning the shoulders more or less fixed, the arms will assume whatever position it takes to connect the shoulders to the hands holding the handlebars (basically the elbows take up the slack).

The idea that you will sit lower if you just lower your bars is not true in most cases, other than the extreme (basically if you can only reach your bars with stretched arms, which is a bad idea based on the Lubberding point, then lowering those barrs would pull down your entire body into an unnatural position. But if that is a position you can sustain, then you can also keep your back in that position when you raise your bars from there and bend your elbows.

Next we’ll look at what this means for performance. Any comments or questions, please leave them in the comments section below or let me know via twitter @gerardvroomen.

20 Responses to “Body position vs bar height – part 1”

  1. Mark Legg Says:

    Another example of bar height setup is watching a rider descend on the brake hoods vs the drops. Typically the rider on the hoods is running a low handlebar setup and is not overly confident or stable in this position during the descent. Aerodynamically descending on the hoods is not as economical as descending in the drops which isn’t any surprise.
    While in the drops if a rider wants to lower their upperbody position to achieve a more aero profile it’s simply a matter of bending your elbows more which follows straight into the Lubberding theory.
    Thanks for posting, it’s an important issue to discuss.

  2. Chris Says:

    Gerard – Your insight is wonderful and greatly appreciated. I had a bike fit a few years ago and while disappointed that the bar/ stem was raised. There was an immediate performance difference as a result. The bar/ stem slammed against the top tube may look cool, but that doesn’t mean it’s right.

    FYI – I just put a down payment on my first Cervelo – an S5 which I am eagerly awaiting!

  3. Chris Says:

    I have problems with bending my elbows. I have not had a pro fit yet. I ‘feel’ like my elbows are bent, but other riders tell me it looks like they are locked. But, when I bend them my head is too low and have a problem looking up. My saddle height is good. My hands go numb during a long ride. Time for a fit.
    Gerard, thank you for the great info!

  4. Chris S. Says:

    I just realized after posting…this is Chris S. Not the lucky Chris waiting for the S5.

  5. David Says:

    When I think about this I realize that when I go from drops to hoods to tops and back during a hard effort I do not change my back, head or shoulder position. Just the position of my hands and bend in my elbows to accomadate the new hand position.

  6. Dale Newnham Says:

    I think the guys over here: http://slamthatstem.com/ need to read and learn!

  7. erikleung Says:

    Interesting post Gerard – we’ve all seen riders’ positions evolve over time and after many seasons of riding and racing. So, how do some of the things that come with more riding – increased sport-specific strength, increased core strength, and flexibility effect a rider’s built-in angles and “stock” setup?

  8. Evan Says:

    I think my stem is staying slammed, Gerard.

  9. Sergio Says:

    Interesting point of view Gerard, particularly when you mention that “changing the handlebar height does not really change the back position, at least not during serious exertion”.

    I wonder if you had a conversation with Tom A. very recently? ;-)

    Best wishes,

  10. wisey17 Says:

    Hi Gerard,
    In your experience with Pro teams such as CSC and then the Cervelo Test Team in its various incarnations, who has the most input into the riders’ positions? The riders themselves, the DS/Coaching Staff, the bike sponsor’s staff? Thanks.

  11. Sergio Says:

    Gerard, the word ‘combat’ in that first paragraph makes me think that it will not be an easy job to convince some of your riders.

    It will be interesting to see how the G-C riders that were riding their S3s using -17° stems with no spacers respond to a higher stack and to this information you are sharing with them.

    Best wishes,

    Sergio

  12. Bill Says:

    Guys, please realize that Gerard doesn’t say that you can’t ride a bike with a slammed stem. He’s essentially saying that you should ride a bike that fits YOU. And, if you have the flexibility, etc. required to ride a bike at an optimal balance between performance and comfort that has a slammed stem, then that is the right bike for you. Fabian Cancellara rides a bike with a slammed stem but then again I’ve heard that he can also comfortably touch his toes while putting his chest fully on his knees. That’s why his stem is slammed. Because it’s appropriate for him.


    • And it’s not even appropriate for him. Ever see him in full effort on the flats? 9 times out of 10 he’s on the hoods, not in the drops. Higher hand position, more aero and faster.

      • Anonymous Says:

        I am impressed Gerard knows that Fabian’s position is wrong. Maybe someone should tell him so he can win Paris-Roubaix for once?

      • Bedirhan Says:

        Anna Posted on Wish I could have gone with you guys. I always want to look back at Hunter and then I alosmt fall over. Typical me LOVE these pictures of the ride.

  13. Anonymous Says:

    probably stop taliing abot it and go SLAM THAT STEM.

  14. Anonymous Says:

    I hate you Gerard, my stem will stay slammed and I will drop some bird poo on your doorstep just to show how much I hate you,


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