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--- understanding_pedal_power [2007-07-11 17:32] – nik
+++ understanding_pedal_power [2007-07-11 17:33] (current) – nik
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 an output of 50 watts for the desired period, the driven device
 will receive 45 watts input.
@@ Line 317: / Line 318: @@
-  - The first is the upright position used by the majority of cyclists around the world.  In this position, the seat, or
+. The first is the upright position used by the majority of cyclists around
-saddle, is located slightly behind where it would be if it were a
+the world.  In this position, the seat, or saddle, is located slightly behind
-seat, or vertically above the crank axis; the hand grips are
+where it would be if it were a seat, or vertically above the crank axis; the
-placed so that the rider leans forward just slightly when
+hand grips are placed so that the rider leans forward just slightly when
-pedaling.  Tests have shown that subjects using this position are
+pedaling.  Tests have shown that subjects using this position are able to
-able to produce the most pedalling power when the top of the
+produce the most pedalling power when the top of the saddle is fixed at a
-saddle is fixed at a distance 1.1 times the leg length to the
+distance 1.1 times the leg length to the pedal spindle at the pedal's lowest
-pedal spindle at the pedal's lowest point.
+point.
-  - The second position is the position used by riders of
+. The second position is the position used by riders of racing bicycles with
-racing bicycles with dropped handlebars, when they are holding
+dropped handlebars, when they are holding the upper parts of the bars.  Their
-the upper parts of the bars.  Their back is then at a forward
+back is then at a forward lean of about 40 degrees from the vertical.  Their
-lean of about 40 degrees from the vertical.  Their saddle height
+saddle height requirements are similar to those of cyclists in the first
-requirements are similar to those of cyclists in the first position.
+position.  (The position of the racing bicyclist who is trying to achieve
-(The position of the racing bicyclist who is trying to
+maximum speed is not suitable for power production on a stationary device.  Even
-achieve maximum speed is not suitable for power production on a
+racing bicyclists sometimes experience great pain after a long time in this
-stationary device.  Even racing bicyclists sometimes experience
+position, and the position is unnecessary on a stationary device because there
-great pain after a long time in this position, and the position
+is no wind resistance to overcome.
-is unnecessary on a stationary device because there is no wind
-resistance to overcome.
-  - The third position is the position used in modern semi-recumbent bicycles. The placement of the center of the pedaling
+. The third position is the position used in modern semi-recumbent
-circle relative to the seat is shown in Figure 4.  In this seating
+bicycles. The placement of the center of the pedaling circle relative to the
-position, the pedaling forces are countered by the lower back
+seat is shown in Figure 4.  In this seating position, the pedaling forces are
-pushing into the seat (which is similar in construction to a lawn
+countered by the lower back pushing into the seat (which is similar in
-chair made of tubes and canvas).  The arms and hands do not need
+construction to a lawn chair made of tubes and canvas).  The arms and hands do
-to remain on the handlebars to perform this function, the way
+not need to remain on the handlebars to perform this function, the way they
-they usually do in the first two positions.  They can remain
+usually do in the first two positions.  They can remain relaxed, and free to
-relaxed, and free to guide the work that the pedaler is powering.
+guide the work that the pedaler is powering.  The upper body too can remain
-The upper body too can remain relaxed, and the chest is in a
+relaxed, and the chest is in a position that makes breathing easier than when
-position that makes breathing easier than when the pedaler bends
+the pedaler bends forward.  The major disadvantage of this position is that,
-forward.  The major disadvantage of this position is that, since
+since the pedaler's legs move forward from the body, it may be hard to position
-the pedaler's legs move forward from the body, it may be hard to
+large, deep equipment like a lathe or saw so that it is in reach without being
-position large, deep equipment like a lathe or saw so that it is
+in the way.  In almost all other respects, the semi-recumbent position is highly
-in reach without being in the way.  In almost all other respects,
+desirable, though not essential.
-the semi-recumbent position is highly desirable, though not
-essential.