Thursday, January 27, 2011

Cadence Case Study: Scott Zwizanksi


Part II: Individual Fit Priorities

Part II in a series of blogs that focus on Scott Zwizanski and his work with Cadence Cycling & Multisport in advance of the 2011 season. For Part I, scroll down.
In our last blog we introduced our work with Scott Zwizanksi, Cadence-coached athlete and time trial specialist, as he prepared for 2011 with his new United HealthCare team. Scott’s new team had him in the A2 Wind Tunnel in North Carolina to hone his aerodynamics, but not before Brady Gibney and Colin Sandberg had a chance to work with him on his position. This week’s blog will focus on just that; individual fit priorities that every athlete has, that allow them to maximize their return come race day.

Let’s start by looking at Scott’s individual fit priorities from a 10,000 foot view, and then break each down and explain how our coaches addressed each one before he stepped foot into the wind tunnel.

Maximize Biomechanical Efficiency
From Scott’s years of being coached by Brian Walton and corroborated by the recent tests we’ve done, we know that Scott as a rider is most powerful at higher RPMs with open hip-angles. With a strong core built from years as a collegiate swimmer, we know that Scott can tolerate positions forward over the bottom bracket. This allows Scott to operate at higher RPMs while also rotating him forward, which could potentially lower his frontal area resulting in better aerodynamics.
Result: Saddle height increased .7cm
            Saddle setback decreased to -5.0cm

UCI Bike Regulations
Unfortunately, bicycle fitting is not limited to only the rider’s capacity but also by Union Cycliste Internationale laws. These laws dictate that a rider and his machine must fall within a certain set of dimensions, or they will be unable to compete in UCI (read, most every professional race) competition. For a breakdown of UCI time trial regulations, see the following article from our friends at Slowtwitch:

This presented a slight issue in Scott’s fit because of his efficiency at higher RPMs mentioned above.  UCI regulations limit the distance behind the bottom bracket that a rider can be to -5cm, and that is as far as we could move Scott forward.
Result: Saddle setback limited to -5.0cm behind bottom bracket

Adaptability
Similar to the concept of economy testing, a riders’ ability to adapt to new positions comfortably is a serious consideration even for a professional cyclist. Often times, amateur cyclists will try to emulate professional cyclists’ positions with long reaches and deep drops. Professional cyclists ride an average of 60,000km a year and have thousands of hours adapting and honing their position without sacrificing power or speed. You wouldn’t get into a 1,000 horsepower Formula 1 car days after learning how to use the clutch in your Honda Civic.

Scott’s had not been spending a lot of time on his time trial bike in the off-season, and had mainly been riding his road and mountain bikes in preparation for the 2011 season. Given our short time frame, assumptions had to be made that in time his body would settle into his new position comfortably. We are lucky to have years of experience coaching Scott and were able to use his expert feedback about the small changes we made to his position.
Result: Drop from saddle to handlebars decreased 3cm







Maximize Economy in the time trial position
As mentioned last week, the term “economy” is a hot button in physiological testing as of late. With economy, we are not just looking at how much oxygen your lungs can intake (maximal oxygen uptake) but how oxygen usage is affected in different positions on the bike. Measuring economy is not only your body’s capacity, but its functional capacity on the bike in different positions.

Our priority with Scott was a bit more complex because we knew his position would change once in the wind tunnel, so our goal was to find the range of high-economy positions that he could hold during time trials. Once the above changes were made to Scott’s position, testing was required to determine if we have found an acceptable range to take to the wind tunnel. Testing was completed over two days on Cadence’s ParvoMedics measurement module to measuring Scott’s heart rate, lactate concentration, VO2, and respiratory exchange. On the first day we tested Scott’s original position followed by a 20-minute rest and then tested again in the new position. On the second day we tested Scott’s new position first followed by a 20-minute rest and then tested again in the old position.


Day 1-Original Position
Day 1- New Position
Day 2- New Position
Day 2- Original Position
Time
VO2
HR
VO2
HR
VO2
HR
VO2
HR
1
40.7
139
41.5
136
39.2
122
40.5
128
2
55.3
162
56.6
157
56.7
150
59.5
156
3
58
167
60.2
163
60.8
158
63.5
163
4
59.5
170
61.6
167
63.1
160
64.8
165
5
59.7
170
62.3
171
65
167
67.2
170
6
61.4
170
62.5
173
66.1
169
67.3
173
7
61.3
174
61.9
174
65.7
169
67
173
8
61.9
175
62.6
176
66.3
173
67.4
175
9
61.5
176
62.9
178
67
174
69.1
177
10
62.4
176
62.6
177
66.2
174
67.2
176


The Results
 A final report sent from Cadence coaches to Scott’s new team director read as follows, “There was no significant, consistent, and sizeable differences to the physiological responses between the original position and the modified position, therefore it is likely that the subject would be likely to adapt to a more aerodynamic position without significant physiological cost.”

If you reference the above graph’s bottom line, you can see for yourself there were minimal differences to Scott’s physiological responses to the two positions. By taking into consideration Scott’s individual fit priorities and testing accordingly, Brady and Colin knew they were sending Scott to the wind tunnel in North Carolina with the best possible position to work from. Please check back soon as we delve into the final blog of our series, Part III: Into the Wind Tunnel

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