"They take away a lot of spectacle and make you race more cautiously," Quintana said. "I'd be the first in line to say they should be banned."
"I think they’re really useful for training, but they take out a lot of drama from the sport," added Valverde. "In competition you should be racing on feelings."
Quintana and Valverde made their joint call during Tuesday's rest day press conference in the Vuelta, 24 hours after Quintana regained the overall lead thanks to a spectacular solo win at the Lagos de Covadonga. He is now 57 seconds ahead of Valverde, with Chris Froome (Team Sky) in third, at 58 seconds.
For some, the Movistar duo's comments may add spice to their sporting rivalry with Froome, who is felt by some to rely heavily on power meter data when tackling climbs. As Froome told reporters on Monday and repeated at his own Tuesday press conference, however, his climbing strategy of riding at his own pace at Lagos de Covadonga had been based mainly if not entirely on his sensations, rather than on data from his power meter.
“I was riding more by feeling today,” Froome said after stage 10, where he had ridden at his own pace very successfully to limit the damage caused by Quintana's attack. “I was just riding with what I felt I could do on the climb in the most efficient way to get up there and not to lose even more time.”
Speaking on the rest day, Froome said: "The power meter's there and I'm aware of the numbers I'm doing, but at the end of the day it is more on feeling and I've got to judge that."
Quintana's comments came after he had repeated that he would have to take more time on Froome should he wish to win the Vuelta, although he was cautious when it was put to him that he could improve in the third week of the Spanish Grand Tour, as he has done previously in other big stage races.
"Normally that's true," Quintana observed, "but at this point in the season, it's late, we've got a lot of kilometres in our legs, and I have no real idea how I will go in the third week. All I know is I have to make the most of my good moment.
"For example tomorrow's stage that finishes the Peña Cabarga, there may not be very big time gaps, although if I'm feeling good, I could maybe get some time."
As for Froome, Quintana noted: "His form is good, he's racing in his own way, and he's going very steadily and then getting better and better on the climbs. So I have to keep a very close eye on what he does."
Quintana said that he is recovering quickly from his crash early on stage 10, "although it still hurts a bit." He was still upset, he added, at having to sacrifice the Olympic Games in order to recover better from the Tour de France and build for the Vuelta. "But it was for the best and I knew my teammates and compatriots could make the most of this situation. It was looking good for us and the medals too [in the road-race], until Sergio [Henao] was unlucky enough to crash."
Going to Rio, Quintana explained, would not have helped his Vuelta preparation. "Getting a stage win here at Covadonga was very good for my morale."
In another intriguing comment, Quintana also revealed that he is weighing up a possible attack on all three Grand Tours in one year, as his teammate Alejandro Valverde has done this season.
"At the moment I have other objectives, but it's something that has attracted my attention," he said, while Valverde noted with a grin that racing the Giro, Tour and Vuelta is not something he would repeat in 2017.
"At my age, once is enough. It's a real challenge, an interesting one, and I don't know how I'll go in the third week, but I'm 36, and that's as far as it goes," Valverde said.
"We're doing well here for now, there, with first overall, second, the lead in the team classification and a stage win. That's a lot of energy for the team to use up, but we're here to win the Vuelta."
Valverde agreed with the widely-held sentiment that the Vuelta is now coming down to a straight duel between his team-mate Quintana and Froome. "Alberto [Contador] is up there, also [Esteban] Chaves, but the two who are closest are Nairo and Froome," he said.
Team manager Eusebio Unzue warned that Foome was not the lone rivals. "Contador is never predictable and he never gives up. I have no doubt that before this race is over, he'll have turned in one of his trademark performances." For now, though, it seems that Movistar are concentrating mainly on how much time they can gain on Froome before the stage 19 time trial.
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