幾年前(2004底或2005)在藍斯·阿姆斯壯(Lance Armstrong)要挑戰環法(le Tour de France)的七連霸前，「發現頻道」，繼「美國郵政」(US Postal)之後成為車隊贊助商，除了車隊名稱改為「發現頻道隊」(Discovery Channel Pro Cycling Team，UCI車隊代號: DSC)，發現頻道也對阿姆斯壯做了詳細的報導，也因此了解到：踩速對騎單車的重要。以往覺得可笑的輕踩高轉速迴旋，原來是職業選手們採用的「秘技」。

阿姆斯壯是高踩速的代表選手，他甚至在上坡的路段依然維持一分鐘120轉的驚人高速迴旋。我從來沒有測過自己的踩速，不過從看了的節目後，上坡就改用輕踩，讓腳下的迴旋速度提高些。

現在我已不再為應付更陡的坡而保留一個檔位了－－因為當踩速提升後，較高速的迴旋自然讓你可以進檔(較高速的檔位)，原本想保留的檔位就出現了；如果可以繼續維持較高速的迴旋，幾十公尺後，又可以進一檔了。成效就比當初想留一個檔位的策略更好，因為有兩個低速檔可以切換了！而且採用輕踩策略，從一開始腳就不用很用力，雙腿肌肉的負擔也較小；不但如此，速度也提升了。

後來對此在網路上做了些研究，－－如果想減肥的話就趕快採用輕踩策略來騎單車吧。簡單地說，重踩使用的肌肉是消耗glycogen, 肌肉裡的醣類；而輕踩是使用slow twitch muscle fiber，消耗的能量是fat脂肪。

2004年，黃色的橡皮圈(腕帶)「Livestrong」意思是堅強地活著，及Trek 推出的黃金版環法六連勝紀念車，大概是最具話性的商品吧。阿姆斯壯設計的黃色的橡皮圈，還造成流行，台灣的麥當勞也推出各種顏色的橡皮圈，不過是印有NBA 球隊的名稱，與單車無關。

Cadence    騎乘節奏

Cadence in cycling is the speed at which your legs turn! It is measured in revs per minute / pedal rotations per minute.

Much the easiest way to measure cadence is with an attachment to your bike computer, but it is also easy to calculate as you are cycling along - keeping an eye on the clock of your bike computer, count how many pedal turns you make in 30 seconds (and double it for a one minute result).

The problem with counting your own cadence while cycling along is that the act of counting and looking at the watch can actually change the speed at which you are pedalling. There are also some circumstances where it is less easy to manually count - going up a steep hill for example.

Once you have counted your own cadence a few times you will quickly gain a natural feel for whether you are turning at 60 rpm or 110 rpm.

Casual cyclists will tend to have a cadence around 60 rpm, professional cyclists up to about 110-120 rpm. Your goal is somewhere between the two. Lance Armstrong was well known for maintaining avery high cadence, around 120, even on steep mountains.

Very broadly speaking, it is a good idea to get used to cycling at a reasonably fast cadence - say 90-100. This can seem unnaturally fast at first, but with practice will become second nature. The principle is that it is less stressful on your muscles if you can pedal faster, but with each turn taking less pressure.

You will notice this very quickly when you get used to turning the pedals faster - cycling in a difficult gear at 50 rpm is much more work for your legs than cycling in an easier gear at 80 rpm - assumaing the same overall speed.

Pedalling at a low cadence is known as 'mashing', while a high rotation speed is called 'spinning'.

In technical terms, cycling at a low cadence with great force uses 'fast twitch muscle fibres' while cycling at a high cadence with less force uses 'slow twitch muscle fibres'. Fast twitch muscle fibres use locally stored energy (glycogen in the muscles) that will run out after an extended period of exercise,and tire easily whereas slow twitch uses fat, much more available in the body and much better able to cope with extensive periods of effort. 

There are still times when you might use slow pedalling (eg that extra steep part of the hill where you are standing up on the pedals), but in general, almost all aspects of your cycling will be improved, from endurance to overall speed, if you can use a target cadence of 90-100 rpm.

This even applies on hills. You should aim to use an easy gear, and keep pedalling at your preferred cadence, rather than make great efforts in a gear that is a bit too hard and in which you can only manage 55 rpm.

As with all cycling training, the best way to attain a goal is simply to try and do it! One approach is:

• Find out your current cadence
• Set an intermediate goal, say 10 % faster than your current level
• Do regular 'intervals' in which you cycle for a couple of minutes at a time at a rate 15-20 % faster than your current level. You can change to an easier gear to do this of course.
• Pretty soon you will become used to pedalling faster, and your cycling will feel better for it.

http://www.road-bike.co.uk/articles/cyclingcadence.php


Danny was pedalling uphill overtaking cyclists who walked bikes. (by Frank 2009.5.9)

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The article of "Cadence" is taken from Road-Bike website at above-stated URL.  The copyright of "Cadence" belongs to its original owner.  Road-Bike is not involved with, nor endorse the production of this blog.