The Perfect Bike Position?

Over the last 8 years I have been studying bike riders and their position on race bicycles. Within this time frame I have seen hundred of different ways of bike fits through bike shops and through coaches. All of these fits seem to be "good" but I always knew that something was missing or could be improved to reach your possible highest level of performance, regardless if you are weekend warrior or a professional!

In 2004, I met John Cobb in Texas and my learning curve went straight upwards. John and I hook up instantly and starting "playing" around with "bike fits" and shared our thoughts. John Cobb has worked for several years with Lance Armstrong during Lance's early 3 Tour de France victories, and other professional athletes on their bike position. With John`s input and my own research I have develop my own unique way of positioning cyclists and triathletes on their machine.

What is the difference between my "Positioning" and a "Bike Fit"?:

A bike fit is used to adjust a bicycle to the rider by its dimensions. Certain components can be changed on a bicycle to make it fit better for the rider. A lot of these changes a made after the rider was measured and a computer formula created numbers how to adjust the bike for the rider. The problem is that these changes are purely analytical created by a machine.

How can a computer know what body type the rider has? What are the riders injuries? What is the riders flexibility? What are the riders complains? What are the riders biomechanical limitations? What events does the rider concentrate on?

The answer is easy: A computer can not know the answers (at least not yet!). At this point I started thinking an researching. Every human is a unique individual with certain habits and special anatomical and physiological limits. The only way of setting up a cyclist and the bike is to work with the riders limitations and conditions to control the riders position on the bike. Due to the nature that every human is a unique individual, a the process of a positioning works out always different! My long term studying of the pedal stroke has shown that we can not have the perfect round standardized pedal stroke. Every individuals pedal stroke is different and it can not be copied. But the recruitment pattern of the muscles while bike riding is similar within bike riders but it is often limited due injuries or a bad fit. The ultimate cyclists goal of a great position is to be comfortable and powerful! All muscle need to work properly. EMG research has shown that different fits can shut down full muscle groups while riding. Most of these muscles are necessary to be powerful and comfortable on the bike. These 2 factors are well depended on each other. A rider only can be powerful if he/she is very comfortable as well. Under this condition all muscles will be recruited properly and the cranks start spinning like a well oiled machine.

A third variable is not always as important: Aerodynamics. A lot of times the most aerodynamic position is not the most comfortable and most powerful position. Due to this fact, I use my experience I have gained while testing in the wind tunnel to judge the benefit or deficit of being super aero towards being more comfortable and more powerful. Very often a few changes on the equipment (for example: water bottle placement on TT bikes or the use of the right wheel or shoe covers etc.) will increase your benefit of aerodynamics more than the super aero position. The benefit of being more comfortable and powerful is most of the times bigger than the gain of drag with being not as aero.

As a conclusion I can state that a perfect position is created when the rider is able to reach his/her physiological limits within the anatomical limitation and not by using a formula and having the bike force the rider beyond these limits. My own tests have shown that riders have increased their Threshold Power by up to 80 watts with a proper change in position.

Nevertheless, my research is not finished and I`m constantly analyzing data to continue developing my bike positioning.

Bjoern

nuun - Active Hydration

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What is nuun and how does it work?
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It is important to mention that nuun does not contain any carbohydrates like other energy or sport drinks. For any exercise over one hour it is very important to consume carbohydrates in form of sport bars or gels. This is the only way to maintain proper working muscles, as carbohydrates (glycogen) are the primary energy source for muscles.
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Ingredients
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Potassium (bicarbonate) 100mg
Calcium (carbonate) 12.5mg
Magnesium (sulfate) 25mg
Vitamin C 37.5mg
Vitamin B2 500mcg
other ingredients: citric acid, sorbitol, sodium carbonate, natural colours flavours, sodium bicarbonate, potassium bicarbonate, polyethylene glycol, magnesium sulfate, sodium benzoate, calcium carbonate, acesulfame potassium, riboflavin-5-phosphate.

The Effect of Pedal Float on Power Output in Individual Cycling Performance

THE EFFECT OF PEDAL FLOAT ON POWER OUTPUT IN INDIVIDUAL CYCLING PERFORMANCE

Ossenbrink, B., Urbannek, T., Haff, G. G..
Midwestern State University, Wichita Falls, Texas

The purpose of this study was to investigate how 0, 5 and 10 degrees of rotational freedom on road cycling pedals affect performance during a 20 km time trial. Ten male and two female elite cyclists volunteered for participation in this study (age: 24.6 ± 6.7, height: 176.8 ± 7.5 cm, weight: 73.8 ± 9.1 kg, bodyfat: 9.1 ± 4.8 %, VO2max: 60.8 ± 7.8 ml.kg.min-1). The present investigation tested the subjects during 4 sessions using road bikes on a CompuTrainer ergometer (RacerMate, Seattle, USA). The first session included collection of biometric data and VO2max cycling testing. Session #2, #3 and #4 were 20 km individual time trials with a 500-meter incline at 9.5 km and 19.5 km. The pedal float was randomly assigned during session #2, #3 and #4. Subjects used 0°, 5° or 10° of pedal float. Performance parameters, peak and average power, peak and average velocity, peak and average heart rate and total time were measured with a Polar Heart Rate monitor (Polar, Kempele, Finland), PowerTap power meter (Cycleops, Madison, USA), and CompuTrainer ergometer (RacerMate, Seattle, USA). There was no significant difference (p > 0.05) between the three pedal float conditions for performance parameters. No significant difference was found comparing the heart rate at 9.5 km and 19.5 km between the float conditions. Only heart rate at 9.5 and 19.5 km was significantly higher at 19.5 km when compared to 9.5 km in the 0° pedal float condition (p=0.01) and 10° pedal float condition (p=0.03). In conclusion it is suggested that rotational freedom present at the pedal/shoe interface of road cycling pedals does not result in a decrease in individual cycling performance as measured by performance parameters power, velocity, heart rate and time during a 20 km time trial. Therefore, it is recommended that cyclists should select a pedal/shoe interface (float or no float) that minimizes the risk of overuse injury at the knee and which adapts the best to their pedal stroke.

Keywords: cycling, pedal float, time trial

Reliabilty and Validity of the Computrainer and Powertap Power Meter

RELIABILITY AND VALIDITY OF THE COMPUTRAINER AND POWERTAP POWER METER

G.G Haff1, B. Ossenbrink2, W.A. Sands3, and M.H. Stone4

1West Virginia University School of Medicine, Morgantown, WV. 2Midwestern State University, Wichita Falls, TX. 3U.S Olympic Committee, Colorado Springs, CO. 4East Tennessee State University, Johnson City, TN.

Assessment of power during cycling with devices such as the PowerTap (PT) and the Computrainer (CT) has become a common tool for determining cycling training load. Little data exists examining the transferability of power values between different power measuring devices. PURPOSE: To compare the performance measures as determined on a CT to those recorded by a PT power meter during two different 20 km time trials. METHODS: Ten trained cyclists (age 24.7 ± 7.2 y, max power 368.9 ± 41.4 W at VO2max, VO2max = 62.4 ± 8.5 ml/kg/min) were evaluated over 4 testing sessions. The first session was used to determine maximal aerobic power, while the second, third (TT1) and forth (TT2) sessions consisted of a 20 km time trial performed on the subjects own bike on a CT and with a PT power meter. Session 2 served as a familiarization trial, while sessions 3 and 4 served as the test conditions. All testing days were separated by 6 days. Average power (AP), velocity (AV), distance (AD) and cadence (AC) were analyzed with an ANOVA. RESULTS: There were no significant inter-day variations on the CT or PT for AP (p=0.39, 2=0.09, 1-=0.13), AV (p=0.08, 2=0.30, 1-=0.42), AD (p=0.11, 2=0.26, 1-=0.35), and AC (p=0.17, 2=0.20, 1-=0.27). The PT exhibited a high reliability with for AP (ICC=0.87, CV=5.6%), AV (ICC=0.67, CV=4.4%), AD (ICC= 0.90, CV=2.0%) and AC (ICC=0.83, CV=2.1%). The CT also exhibited high reliability with AP (ICC=0.78, CV=7.0%), AV (ICC=0.76, CV=3.6%), AD (ICC=0.95, CV=1.6%), and AC (ICC=0.76, CV=2.4%). Significant differences were determined between the devices for AP (p=0.003, 2=0.68, 1-=0.95), AV (p<0.001, 2=0.90, 1-=0.10), and AD (p<0.001, 2=0.82, 1-=1.00).


CONCLUSION: The CT and PT provide reliable but different measurements of power, velocity, and distance. PRACTICAL APPLICATION: Cycling coaches who use the CT to determine power training zones should be cautious when prescribing training intensities which are monitored with the PT.

Acknowledgment: This research was partially supported by the Saris Cycling Group, Madison, WI.