Often when cyclists come to see me for a bike fit they look at me with disbelief when I raise their handle bars. Too often my clients are set up in a very aggressive position with the bars slammed low. This position looks fast but often leads to discomfort. Their justification for the bars low is for aerodynamic benefits. So they think:)
How does raising your handle bars make you ride faster? Well it enables the rider to get even lower in a very stable position by resting their wrists and fore arms on the handle bars while holding onto the hoods. By using skeletal support, the rider can relax the torso even with bent elbows (this is another benefit, ease of breathing under athletic duress). This position offers a lower profile than having their hands on the drops. Sure this position sounds faster, but where is the proof you ask?
A study by Professor Nathan Barry, et al (2015), provides a detailed analysis of how much drag you can reduce if you bend your arms and torso in addition to where you put your hands.
Barry began his study by reviewing previous studies that report “the drops posture reduces drag by up to 12% compared with the hoods posture.”
Then Dr. Barry conducted wind tunnel tests of common road cycling postures with the cyclist's hands on the hoods and drops position. He reports significant power and drag data to sustain an established speed in these varied positions. Reference the photos and table shown from his study.
By placing hands from the hoods to the drops (Posture 1 to Posture 2) without changing or bending the arms or torso has little benefit with only a 3% reduction in drag and power required or 13 watts at 45kph/28mph. This position gives the rider a 10 second benefit on a 40K/25m course.
HOWEVER, if the cyclist remains on the hoods but bends their forearms in a horizontal manner (Posture 5), a reduction in drag and power requirements is significant to 14% less drag or 58 watts savings than not bending the fore arms.
Additional "Need For Speed" Tid Bits coming soon:)
Yours in Cycling and Fitness,
President of Fun
May Street Bicycles is not your typical bike shop. Sure we sell awesome bicycles, provide bicycle repairs, and rental bikes all at great prices. But we do a great deal more such as dynamic bike fitting, metabolic testing, altitude training, and personal training.