Power Output in Breakaways

In two recent posts covering relative power output in the 2020 Tour de France and showing the impact of stage characteristics on power output, I made the claim that power output is higher for riders in the breakaway than otherwise. This is likely not a controversial statement for anyone, but in this post I’ll show that breakaway riders are required to produce more power than normal on the days they ride ahead of the peloton.

My data-set comes from Pro Cycling Stats which have collected kilometers before the peloton for all World Tour races in 2020. There are 54 race days in this data-set where at least one rider rode ahead of the peloton. I linked this data to my stage level power output data. For power output, I’m using the riders’ relative power output compared to their average power output on all stages. For example, James Knox had a normalized power of 258 watts in stage 5 of 2020 UAE Tour which was 101% of his average normalized power (255 watts) in all stages.

In total, I have 1417 rider race-days with any breakaway out-front where I have power output (across 54 unique races). About 10% of those race-days have >0% of the stage in the breakaway.

On average, the riders in the breakaway have done 106% of their average normalized power while spending an average of 35% of the stage ahead of the peloton. The riders not in the breakaway have done 98.5% of their average normalized power.

The graph above shows how much higher relative power output is depending on percentage of stage spent in the breakaway. Riders who a higher percentage of the stage in the break have higher relative power output. This relationship holds within stages as percentage of time in the breakaway is positively associated with power output in 49 of 54 stages measured – with a median coefficient of 0.14. That means a rider who spends the entire stage in the breakaway vs one who spends none of the stage in the breakaway will output 14% more of their average normalized power.