Tuesday, May 29, 2012

Hesjedal’s TT position

MILAN, Italy (VN) — After three weeks of pink jersey hot potato, Sunday’s race of truth put forth its final judgment on the twin leaders of the Giro d’Italia. Ryder Hesjedal’s 16-second final margin is the smallest since 1974, proof positive that every second does indeed count.

The victory came on the back of the three Giro time trials, which balanced Joaquim Rodríguez’s (Katusha) early time bonuses and sharp final-kilometer attacks in Hesjedals’s (Garmin-Barracuda) favor. The Canadian took 47 seconds in the final TT, 14 seconds in the prologue, and his team took five seconds in the stage 4 team time trial. Without those 66 seconds, gained inch-by-inch in races against the clock, Hesjedal would have fallen to the Spaniard’s time bonuses and high-mountain attacks.

Position and equipment play a central role in time trials, and Hesjedal and the Garmin staff have been at work optimizing both since the lanky rider’s GC abilities were exposed in the 2010 Tour. Hesjedal’s time trial position has changed dramatically since that summer, resulting in lower drag figures and higher power output, according to Garmin’s director of sport science, Robby Ketchell.

“Being a really tall person like he is, tall and skinny, it’s hard to get aerodynamic,” Ketchell explained shortly before the 6’2”, 160-pound Hesjedal toed the start line in Milan. “We had to tweak things over time.”

Ketchell has played a key role in those tweaks, tackling the aerodynamic problems presented by a rider of Hesjedal’s stature. The two have spent hours in the wind tunnel and on the road with Ketchel’s BAT Box (basically a mobile drag calculator) over the past two years, making changes big and small to Hesjedal’s bike and position.

“The process evolved after the 2010 Tour de France, when we realized that he could do a good GC in a grand tour. We knew then that his time trial at the time was something he needed to focus on, so we set about optimizing his position,” Ketchell said.

In 2010, Hesjedal used a very wide arm stance, with his elbows situated almost directly in front of his knees and his head and neck hunched down in between them. The position was low, but not particularly narrow. Ketchell saw room for improvement.

In 2011, Hesjedal’s arm rests were raised and narrowed, bringing his elbows and hands closer together while also raising his arms a bit. Narrowing his frame decreased drag, even with the higher overall position. “Last year’s position was probably a mid-point between 2010 and now,” Ketchell explained. “We’ve just gradually gone to a more aero but also more relaxed position.”

Balanced against outright drag reduction is the need to maintain or improve power output. The fastest position in the wind tunnel won’t be the fastest on the road if the rider can’t produce the watts required.

Raising Hesjedal’s arm rests slightly allowed him to increase power output, while narrowing his arms didn’t decrease the watts produced. The result of the higher, narrower position was an improvement in both parts of the TT equation.

For this year, armrest height and width have remained the same, but Hesjedal has swapped to S-Bend bars to bring his hands up a bit higher. The Canadian is now more relaxed, more powerful, and more aerodynamic than ever.

“We’ve tried a lot of different things with the head and the shoulders but just found that when he’s relaxed he’s more efficient,” Ketchell continued. “He can produce a bit more power, and he’s more comfortable so he can focus on the effort.”

That effort, years of work on the part of both Hesjedal and the staff behind him, bore fruit on Sunday with the first-ever grand tour victory for Garmin, and Canada. But the optimization will only continue, now with an even more intimate awareness of the value of every second.

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