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This is something I've been pondering for a while, but a recent question How much faster when using drops and particularly Weiwen Ng's answer prompted me to give it more thought.

It's often said that most of the time on a drop bar bike is spent on the hoods, and that feels plausible, but I know with sustained headwinds I've ridden a long way in the drops (and much of the rest on the tops for a stretch on the rare sections out of the wind). To plug in to calculators, and for curiosity, how might I measure the proportion of a (long) ride spent in various positions? I'd assume a solo ride, so any solution would need to be mounted on the bike and not affect riding (too much) though a difference between solo and group rides would be particularly interesting and may explain some comfort issues. Alternatively published data would be of interest, though very limited interest if it relates to pro races.

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I imagine one could build something with thin capacitive sensors under the bar tape (or the rubber of the hoods) and a microcontroller. Here is a board with 5 touch inputs you could simply wire up if you have some basic knowledge of electronics and microcontroller programming.

Alternatively you could record the ride on video (mount a wide-angle camera to the bike somewhere) and manually analyze it (or train some machine learning model to distinguish between the three main positions).

Maybe even data from an orientation sensor or accelerometer on the back of the rider would be sufficient to distinguish between the positions. Try putting a smartphone into your jersey’s back pockets and record the sensor data.

However, I doubt the end results would be very useful. Which hand position you pick highly depends on terrain, wind, intensity of the ride, geometry of the bike (and drop bars), the rider, your seating position etc.

I think generally one mainly adjusts the seating position for the hoods because the assumption is that you’d spend most of the time there. So “per definition” the hoods should be the main position. If they are not it means you should adjust your handlebar position.

Also keep in mind that even though there are only 3 main hand positions there are countless variations. For example there is a big difference in gripping the drops right at the end (feels like your shoulders are almost above the hands) vs. at the bend of the bar with elbows bent and a very aggressive riding position.

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  • 1
    Some good points there. I actually have an arduino that I could hook some sensors up to if they're sensitive enough to work through bar tape and gloves, though I'd have to add storage for the data. I tend to only use the bend when I'm in the drops so 4 sensors should do. I doubt back angle would be distinctive enough especially with hills. A camera off the bike would be ideal, but on the bike might work if very wide angle and perhaps on the aero bars. With distinctively coloured gloves and jersey you could probably do it without AI
    – Chris H
    May 19 at 7:16
  • While the hoods are still the default, for long rides it's common to set the bars higher than for faster rides, and use the drops more willingly.
    – Chris H
    May 19 at 7:18
  • @ChrisH Just add four regular clicky buttons. When one is pressed, it selects that mode and stops counting the previous. Probably easier than playing with capacitive sensors.
    – MaplePanda
    May 19 at 23:10
  • 1
    @MaplePanda: But how do you mount clicky buttons in a way which doesn’t interfere with normal riding? Capacitive sensors can just be a wire wrapped around the bar.
    – Michael
    May 20 at 5:07
  • 1
    It should also be passive. Typical case: suddenly come to a junction or busy bit of road on the drops; switch to hoods, sit up, click down through the gears while braking and checking around.Stay on the hoods for the duration of the busy bit, which could be a while. That's not when you want to be fiddling with buttons or remembering to. I thought about pressure pads under the bar tape but easily-available commercial ones are rather large
    – Chris H
    May 20 at 6:17
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The cheap solution would be to obtain a bunch of stopwatches. Label one for tops, one for hoods, one for drops, etc. When you switch hand positions, stop the current stopwatch and start the applicable next one.

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  • 1
    I like cheap and cheerful. Whether I'd remember or not is another matter!
    – Chris H
    May 19 at 7:20
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    The limits of human memory and attention is one reason I didn't suggest something like a rider survey (if you wanted to obtain information about the average cyclist's distribution of time in various positions), or manual recording.
    – Weiwen Ng
    May 19 at 13:48
2

This answer addresses only how someone could measure the proportion of time spent in various hand positions. Leomo makes motion capture sensors that can be used in bike fit. I have never used them, and I don't even do bike fits, but my understanding is that right now they are still a niche item. In any case, it seems like it might be possible to use motion sensors mounted on your arms to automatically record the proportion of time spent in various positions. If Leomo hasn't already done this, one thing I would want to see is the user or Leomo validating that the sensors can correctly distinguish between body positions on the road - this would require a controlled test. I don't think these are practical for most individuals to use, unfortunately, with the first barrier being the cost.

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  • I suspected there would be a product I couldn't afford! That suggests an idea: accelerometers in a phone, though I doubt a single sensor could give an arm position unambiguously as the forearm position will be very similar for aero hoods and aerobars, the upper arm position for hoods, drops (some fits) and aero hoods
    – Chris H
    May 18 at 13:38
  • 2
    Velosense.com is devloping a body position sensor (the Zenith) and an airspeed sensor for cycling. I think they may still be in pre-production. Other than that, some friends have been experimenting with body cameras to test body positioning and movement during aero tests. Bodyrocket.cc is touting their new set of body sensors, but I haven't seen one yet so I don't know how or whether it works.
    – R. Chung
    May 18 at 15:20

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