Comfort trumps aero? Or does it?
Comfort trumps aero
Recently I've been working on an article and video based on the "comfort trumps aero" rally cry that you hear often about race bikes in general, but more specifically in regards to triathlon and time trial bikes.I've seen the "comfort vs. aero" discussion mostly center on the idea that if your're uncomfortable and forced to get out of the aero position then you're losing the aerodynamic battle. This, I don't think, is up for debate -- it should be glaringly obvious.My question has more to do with even when you can spend the entire race in the aero position, at what point does being too aggressively aero cause enough discomfort to affect power output? We know that pain, or even the anticipation of pain, can inhibit motor output and control, but how relevant is this to the cyclist with moderate shoulder discomfort or occasional low back pain on the bike?At the heart of "comfort trumps aero" there is truth. But it's important to remember that this truth likely isn't absolute:It may be acutely true for an iron-distance triathlete spending anywhere from 5-8 hours on their bike. Makes sense that the longer the rider is on the bike, the more critical it is to be comfortable since being on a bike for 7 hours, even in the best of circumstances, is a recipe for discomfort.What about the Master's time trialist whose races are generally 8-20 miles in length? It can't possibly apply in equal measure in that scenario. Shouldn't there be a more acceptable amount of baseline positional discomfort in order to achieve significantly improved aerodynamics? I would argue strongly that there is.This is what can make certain bike fitting such a challenge -- there's an element of weighing trade-offs since we're balancing power generation, discomfort, and aerodynamics (not to mention the often overlooked respiratory dynamics). This is very challenging to do.Recently I had a client come in for exactly this sort of bike fit as she was planning to race time trials next season. We finished with a position that caused her really no discomfort for the first 30 minutes of any ride. Then she'd experience some mild discomfort in her shoulders that she'd be able to intermittently stretch out through the hour mark. At the 90-minute mark is when she'd begin to want to get off her bike for more relief. But seeing as how it was rare for her to race anywhere near 90 minutes -- most of her races were 18-25 miles long putting her on the bike for 45-60 minutes -- this was entirely acceptable, especially given that her position was measurably more aerodynamic.How did we come to this conclusion during our bike fit? No, I don't have a wind-tunnel in my studio. We came to that position through repeated field tests using her power meter. Over the course of many rides we could see a trend that the new position was faster over the same courses given the same power output -- not a perfect, but more than acceptable indicator of improved aerodynamics. Plus we were able to assess her power output and it's dropoff throughout the course of a ride -- if it began to vary significantly from her power profile in her road bike position (which is very comfortable), then we'd know that we were a bit too aggressive.Important Note: Having spent some time in a wind tunnel you learn that there are a few postural changes that are a good bet for improving aerodynamics. It should be noted that wind tunnels, and aerodynamics more broadly, aren't an "A + B = C" scenario. I know reading the magazines and hearing about how many seconds are saved over 40 km and yaw angles, can make it seem like a simple science, but there is a lot of chaos involved. For instance, you can put together the "most-aero" frame and the "most-aero" wheels and they can test worse than if you had a "less" aerodynamic wheelset on there. It is for all these reasons that I'd be careful about taking aerodynamic advice from a fitter that hasn't spent time in a wind tunnel.This is a fly-over view of this issue but it brings me to the question I ended up with in doing my research: How much pain is too much?Or more specifically: At what level of pain/discomfort does the body begin to significantly down-regulate power generation capabilities?The truth is we may never know the answer to this question because pain is a very messy subject in research. The difficulties begin with the fact that the experience of pain is subjective -- when using a 20-point pain scale, the same insult might be rated an "8" by one person and a "14" by another. Then toss in differences in motivation (sufficiently motivated, we can tolerate more discomfort without effect on motor tasks) chemicals (caffeine has been shown to improve pain tolerance) and familiarity (new or infrequent insults tend to elicit more discomfort), and it begins to come clear why it's such a difficult thing to study objectively.So I'm curious if anyone has found more interesting research regarding pain and motor output/control? I'd love to see what you guys can come up with, so put links in the comments below or email me what you find...