There still remains a topic pertaining to cadence and the search for the optimal cadence that needs to be looked at, and that is the different cadences utilized in the different sub-disciplines of cycling.
More specifically the Time trial (TT) and the Road race (RR).
But before we jump in, let's break it down a little more. What are the factors that might play a role in different cadences being selected by the cyclist?
TIME TRIALING:
Goal of the event -
The TT has one purpose: to see how much pain the cyclist can tolerate over the race course. It is commonly called the the Race of Truth because there is no where to hide - it is you, your bike and the clock.
It is all about generating the highest wattage possible, for the duration of the race. This requires the individual to push a hard gear ratio which translates into a lower cadence (generally from 60-80rpm).
Length of the event -
For the most part, the TT is much shorter than the Road race. TT can be anywhere from 7km to 60km in lenngth (obviously we are not talking Ironman here).
This allows the athlete to put out higher numbers (wattage and speed), for the shorter time.
The race course -
TT courses tend to have a more undulating terrain, with fewer extreme climbs and descents, allowing for faster average speeds and wattages, and faster times.
Body position -
The aero position in the TT changes the biomechanics of the pedaling action. Because the body is moved forward on the bike, the Quadriceps and Gluteus Maximus muscle group become the primary power generator. Both extremely large, and extremely powerful.
Perfect for the requirements of the TT (ever looked at the size of the guys quads who can TT well?)
Energy conservation -
This is not a major priority in the sport of TT.
So crank down that gear ratio and push those pedals.
Road Racing
Goal of the event -
RR is much the same as TT in that the goal of the event is get from one point to another in the shortest time.
However, the goal is generally to cross the finish line first, to get the glory. There are also many team tactics and techniques utilized in the RR to complete the event.
Length of the event -
This is alot more variable, as races can be from 30km to 300km. This will have a very big impact on the power and the speeds put out during the event.
If riding a 300km event, most cyclists would not push heavy gears and have a high average Wattage at the end of the race.
The race course -
RR are designed to test all the skills of a cyclist, so they generally include some hills (which can be extremely steep), some challenging long flat sections, and with uphills must come downhills too.
Body position -
The position of a RR is a less aggressive and less aerodynamic one. This more "upright" and slightly more back on the saddle, means that the muscles doing the work now include more Hamstring and less Quadriceps.
This means slightly a group of less powerful muscles is now participating, so the gear selection and the cadence becomes more important.
Energy conservation -
Riding for 3+ hours means that it is all about conserving energy. Riding at a low cadence, pushing out a hard and heavy gear, will blow through the bodies Glycogen stores in no time.
Using a slightly higher cadence will allow the STF to be able to process Lipids (fats) more effectively, thus sparing the Glycogen, for when it is really needed.
From the 5 points listed above, we can get a better understanding of how the demands of the sport place different demands on the body, and this in turn has an impact on the pedaling speed selected.
The bottom line is that Cadence should be something that is experimented with. You should try different cadences and see where you are most comfortable, and most effective.
