Under certain circumstances, the formula for calculating Estimated Watts will underestimate your Ride Load. 

These circumstances include particularly windy rides, rides that are all downhill, or rides with a heavy wind in only one direction. So, we've made it possible to manually adjust your Ride Load so that your training stays on target. 

To do this, simply enter a number that better describes the load from your ride in the Ride Load field of the ride upload or edit page.

See this article for more info about Ride Load numbers.