Horner traces the problem back to the final road stage of Tirreno Adriatico, a gruelling day which saw the riders tackle the wall-like Muro di Sant'Elpidio climb in wet, cold conditions. He believes a combination of those weather conditions plus the nature of the climb is what aggravated his leg
“I don’t think it was equipment related at all,
but completely down to that stage. I was with Nibali when he was attacking on the last time up that very steep climb. At that point in time it had been raining, it had been cold, it was coming to the end of a tough six hour race. The climb is so steep that I had to adjust my position dramatically on the bike, so that the back tyre didn’t spin…you have to keep weight on the back tyre. Also because the gearing was so large, I had to stand up because you are pushing twenty rpms up this climb.
“My belief is that it was the equivalent of doing one of the hardest bike races in the world, then jumping off multiple times during that race, going to the gym and doing one legged squats. I am pretty certain that is what did it, because it was sore the next day for the time trial.
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