Does climbing differ from flat riding? Before you jump to conclusions and say "of course it does", read on...

1) Climbing involves raising your mass from one level to another. The amount of potential energy you gain by climbing is E = mgh, where m is mass in kg, g is gravitational constant in m/s/s, and h is vertical height in m.

This equation explains why ANY climbing requires effort, regardless of how fast you climb. It also explains why slow flat riding requires no effort - no energy is gained.

2) Your fitness will dictate exactly how fast you can climb. Ignoring wind resistance (just for now), the grade of the road together with your forward speed determines the rate of climbing, or the rate at which you gain potential energy. A constant rate of gaining energy equates to a certain power output by your body. And the amount of power (in watts) your body can put out at a sustained level is determined by your fitness.

So, vertical climbing rate is directly determined by your fitness.

Now on to flat riding.

3) Flat riding (by flat I mean zero gradient) involves no gain of energy, so from that point of view, no effort. However, there is wind resistance (and rolling resistance and so on), which requires effort to overcome.

4) Wind resistance is a function of your speed. This means, that for every constant speed, there is a certain power output required to maintain that speed. The higher the speed, the higher power (in watts) is required to maintain that speed.

So here is the final part of the argument:

Since every rate of climbing equates to a certain power output, and since every flat constant speed also equates to a certain power output, it follows that climbing at a certain rate is the same as riding flat at a certain speed, ifthose two have the same power.

Soooo, how is climbing different from flat riding??? Is the question "Are you a good climber" meaningful at all? If someone answers, no they suck at climbing but are OK on the flats, that is contradictory.