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understanding_pedal_power [2007-07-11 17:28] – external edit 127.0.0.1understanding_pedal_power [2007-07-11 17:33] (current) – nik
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 Technical Reviewers; John Furber, Lawrence M. Halls, Lauren Howard Technical Reviewers; John Furber, Lawrence M. Halls, Lauren Howard
-[[mailto:vita@vita  .org]] +vita@vita.org
  
 Published By VOLUNTEERS IN TECHNICAL ASSISTANCE 1600 Wilson Boulevard, Suite 710, Arlington, Virginia 22209 USA Telephone: (703) 276-1800    Fax: (703) 243-1865 E-Mail: Published By VOLUNTEERS IN TECHNICAL ASSISTANCE 1600 Wilson Boulevard, Suite 710, Arlington, Virginia 22209 USA Telephone: (703) 276-1800    Fax: (703) 243-1865 E-Mail:
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 Understanding Pedal Power ISBN: 0-86619-268-9 [C]1986, Volunteers in Technical Assistance Understanding Pedal Power ISBN: 0-86619-268-9 [C]1986, Volunteers in Technical Assistance
- 
  
  
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 an output of 50 watts for the desired period, the driven device an output of 50 watts for the desired period, the driven device
 will receive 45 watts input. will receive 45 watts input.
 +
 +
 +
  
  
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-    o  The first is the upright position used by the majority +1. The first is the upright position used by the majority of cyclists around 
-of cyclists around the world.  In this position, the seat, or +the world.  In this position, the seat, or saddle, is located slightly behind 
-saddle, is located slightly behind where it would be if it were a +where it would be if it were a seat, or vertically above the crank axis; the 
-seat, or vertically above the crank axis; the hand grips are +hand grips are placed so that the rider leans forward just slightly when 
-placed so that the rider leans forward just slightly when +pedaling.  Tests have shown that subjects using this position are able to 
-pedaling.  Tests have shown that subjects using this position are +produce the most pedalling power when the top of the saddle is fixed at a 
-able to produce the most pedalling power when the top of the +distance 1.1 times the leg length to the pedal spindle at the pedal's lowest 
-saddle is fixed at a distance 1.1 times the leg length to the +point.
-pedal spindle at the pedal's lowest point. +
- +
- +
-    o  The second position is the position used by riders of +
-racing bicycles with dropped handlebars, when they are holding +
-the upper parts of the bars.  Their back is then at a forward +
-lean of about 40 degrees from the vertical.  Their saddle height +
-requirements are similar to those of cyclists in the first position. +
-(The position of the racing bicyclist who is trying to +
-achieve maximum speed is not suitable for power production on a +
-stationary device.  Even racing bicyclists sometimes experience +
-great pain after a long time in this position, and the position +
-is unnecessary on a stationary device because there is no wind +
-resistance to overcome.+
  
 + 2. The second position is the position used by riders of racing bicycles with
 +dropped handlebars, when they are holding the upper parts of the bars.  Their
 +back is then at a forward lean of about 40 degrees from the vertical.  Their
 +saddle height requirements are similar to those of cyclists in the first
 +position.  (The position of the racing bicyclist who is trying to achieve
 +maximum speed is not suitable for power production on a stationary device.  Even
 +racing bicyclists sometimes experience great pain after a long time in this
 +position, and the position is unnecessary on a stationary device because there
 +is no wind resistance to overcome.
  
-    o  The third position is the position used in modern semi-recumbent +3. The third position is the position used in modern semi-recumbent 
-bicycles.  The placement of the center of the pedaling +bicycles. The placement of the center of the pedaling circle relative to the 
-circle relative to the seat is shown in Figure 4.  In this seating +seat is shown in Figure 4.  In this seating position, the pedaling forces are 
-position, the pedaling forces are countered by the lower back +countered by the lower back pushing into the seat (which is similar in 
-pushing into the seat (which is similar in construction to a lawn +construction to a lawn chair made of tubes and canvas).  The arms and hands do 
-chair made of tubes and canvas).  The arms and hands do not need +not need to remain on the handlebars to perform this function, the way they 
-to remain on the handlebars to perform this function, the way +usually do in the first two positions.  They can remain relaxed, and free to 
-they usually do in the first two positions.  They can remain +guide the work that the pedaler is powering.  The upper body too can remain 
-relaxed, and free to guide the work that the pedaler is powering. +relaxed, and the chest is in a position that makes breathing easier than when 
-The upper body too can remain relaxed, and the chest is in a +the pedaler bends forward.  The major disadvantage of this position is that, 
-position that makes breathing easier than when the pedaler bends +since the pedaler's legs move forward from the body, it may be hard to position 
-forward.  The major disadvantage of this position is that, since +large, deep equipment like a lathe or saw so that it is in reach without being 
-the pedaler's legs move forward from the body, it may be hard to +in the way.  In almost all other respects, the semi-recumbent position is highly 
-position large, deep equipment like a lathe or saw so that it is +desirable, though not essential.
-in reach without being in the way.  In almost all other respects, +
-the semi-recumbent position is highly desirable, though not +
-essential.+
  
  

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