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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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| - | - 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. | + | 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' | + | |
| - | - The second position is the position used by riders of | + | |
| - | 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. |
| - | lean of about 40 degrees from the vertical. | + | 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 | + | maximum speed is not suitable for power production on a stationary device. |
| - | 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. | + | 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 | + | 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. | + | |