COURSE ANALYSIS FOR 2003
This year's event is quite unlike recent years, as there are
extended undulating sections. Surprisingly, though, analysis shows that the
secret is in the climbs! That extra bit of effort on the climbs will allow you
far more time for the long undulating parts.
As usual, the downhill sections
are not quite as important. This is because you spend little time descending
anyway, so any savings do not amount to much. This is probably as well as the
descents are mainly narrow and twisty this year.
I have done some sums based
on finishing the course in 10 hours. (harder than it sounds this year!)
Supposing you decide to climb at a moderate rate
Terrain | Length | Typical Speed | Time |
Climbs | 17 miles | - | 3h 48m |
Descents | 25 miles | 25 mph | 1 hours |
Rests | 1 hour | ||
Undulating | 82 miles | 19.4 mph | 4h 14m |
Total Time | 10h 2m |
This is based on 150 Watts climbing power for a rider + bike weighing 200lb (12 stone rider + 32lb of bike,clothes,water etc). Covering 82 miles of undulating terrain at 19.4mph would take some doing!
If you ware wondering what 150W represents, or what the climbing speed was - all will be revealed when you read on!
Increasing your climbing power to 200W gives you far more time for the undulating section, so your speed on these sections becomes more feasible.
Terrain | Length | Typical Speed | Time |
Climbs | 17 miles | - | 2hr 48 |
Descents | 25 miles | 25 mph | 1 hour |
Rests | 1 hour | ||
Undulating | 82 miles | 15.76 mph | 5hr 12m |
Total Time | 10hrs |
The extra effort put into climbing means that you only need to do the undulating section at 15.76 mph average. This is far more feasible. In fact, with the help of the huge pelotons, you may be able to acheive a better average speed on the undulating sections than this. As always there is a happy medium. A good climbing power might be 175 Watts. We then get:
Terrain | Length | Typical Speed | Time |
Climbs | 17 miles | - | 3hr 14m |
Descents | 25 miles | 25 mph | 1 hour |
Rests | 1 hour | ||
Undulating | 82 miles | 17.2 mph | 4hr 46m |
Total Time | 10hrs |
This probably represents a good compromise target for the many riders who's target is to complete the Etape successfully. Climbing at these speeds for long periods requires a fair amount of training for most people!
MEASURING YOUR WATTAGE.
One way to measure your wattage is on an
exercise bike or turbo trainer with a well calibrated power
meter.
Alternatively, find a convenient long hill with a steady gradient,
cycle up it! Then find the gradient from an OS map (rise in meters/distance in
meters). Alternatively some hills have gradients marked, or there are other
simple ways of measuring gradients
Then use the simple formula:
Power (Watts) = 2 x Weight(lb) x Speed(mph) x Gradient (as a fraction)
For example, suppose you weigh 200lb with your bike, and want to climb a 7.5% gradient at 5mph.we get:
2 x 200(lb) x 5(mph) x 0.075(gradient) = 150 (Watts)
This formula will only work for low speeds less than 10mph when rolling resistance and wind resistance are small. Also bear in mind that you need to consider a power level that is sustainable for over an hour. CLIMBING SPEEDS