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understanding_pedal_power [2007-07-11 17:31] – 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 | 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 | + | 1. The first is the upright position used by the majority of cyclists around |
- | of cyclists around the world. | + | the world. |
- | 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. |
- | pedaling. | + | 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' |
- | saddle is fixed at a distance 1.1 times the leg length to the | + | point. |
- | pedal spindle at the pedal' | + | |
- | + | ||
- | + | ||
- | 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. | + | |
- | 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. | + | |
- | 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. | ||
+ | saddle height requirements are similar to those of cyclists in the first | ||
+ | position. | ||
+ | maximum speed is not suitable for power production on a stationary device. | ||
+ | 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 | + | 3. The third position is the position used in modern semi-recumbent |
- | bicycles. | + | 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). |
- | chair made of tubes and canvas). | + | 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 usually do in the first two positions. | + | guide the work that the pedaler is powering. |
- | 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. |
- | position that makes breathing easier than when the pedaler bends | + | since the pedaler' |
- | forward. | + | large, deep equipment like a lathe or saw so that it is in reach without being |
- | the pedaler' | + | 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. | + | |