Lance Armstrong on his time trial bike. Not as aero as some, but still fast! Photo: Kevin Saunders
While bicycle technology has changed by leaps and bounds, fitting concepts, particularly with triathletes, have remained remarkably constant. Dan Empfield of slowtwitch.com writes in his article, F.I.S.T. Axioms, 1) Most pro triathletes ride alike, 2) Fit and trim age group triathletes can easily adopt the same positions ridden by the pros, 3) Bodies are smart and can be trusted, and 4) the optimized tri position requires moderate athleticism. I have come to different conclusions in the 25 years that has brought me to the BalancePoint™ positioning system. Here are my thoughts:
- Bicycle positions can be optimized to a finer degree than simply “like” a pro.
- Just because a pro is fast does not imply that he or she has the best position.
- Because muscles do not originate or insert exactly the same for all people, a generic “position” based on adaptation to pro’s positioning 15 years ago makes no sense for all people.
- Not all athletes are “fit and trim” and yet all deserve to be optimized for comfort and power.
- Power trumps aero regarding positioning, to a point.
- Comfortable aero positions that allow one to stay in the aerobars the entire event are critical to going consistently fast.
My initial research into the relationship between power and aerodynamics was based on a coach who was also the coach of a very famous professional time trialist. I can’t break confidentiality but can mention that they were able to get this individual extremely aerodynamic in a wind tunnel, to the point that 5 pounds of drag was all that was imposed while going 30 mph. The only problem was, the rider was quite slow in this position. It turned out to be quite a bit faster to move the rider to a more powerful position and give up some aerodynamics.
John Cobb, aerodynamic guru who spent countless hours putting people in aero positions, noted that the bike racer time trialists were much faster than the triathletes. He came up with the “Slam” position that is quite similar to that which is used in ITU draft legal triathlons to this day. In fact, bike racers use that position without aerobars by putting their forearms on the handlebars when at the front of a fast peloton or when bridging a gap.
Triathletes defend the “aggressive” position by stating that “You have to do the run afterwards” which doesn’t support the hyper aero position but does explain why triathletes race at sub-threshold levels. The issues I have with the aggressive position are twofold: 1) the position is very quad centric and 2) the glutes cannot help share the load as well placing more effective load on the quads.
This imbalance of muscle recruitment suggests that many triathletes arrive at the transition with a worse bike time and are more fatigued as well beginning the run. My observations are that a well balanced athlete will have a faster bike split and will be fresher on the run as well. This is proven many times by athletes that have their position assessed by our BalancePoint™ system and then do testing on known courses. Not only do they report lower heart rates but increased speeds, suggesting that the reduction in aerodynamics is more than offset by increases in power through efficiency.
A final observation which will be addressed in future writings can help explain why some people can assume a very aggressive position and generate power while some others are much more upright. I am in the preliminary stages of research but I am interested in the origin and insertion of glute muscles that could help explain this difference. Some people have glutes that are much higher with respect to the acetabulum and some much lower. This could make a huge bio-mechanical difference.
From a performance standpoint, the BalancePoint™ system accounts for these differences and one can worry less about the “why” and more about results. One thing is certain, though. There is a point where the trade-off in aerodynamics will result in enough power to make it worthwhile. My job is to continue to find that position on you.
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Interesting article… it’s also probably good to note that as one is riding, there are certain times that aero effects are not as effective (e.g. slow, steep climbs with a good tailwind – rare, but it happens
). This was also mentioned by Kristin Armstrong in one of her recent time trials, where she was not in the aero position while climbing. Sitting up helps to give some muscle groups a break and recruit others.
Hi Carlo, Thanks so much for the great comment. You are correct here!