By Tom Taylor

Red Bull doesn’t do anything by halves. When the energy drink manufacturer decided to get into Formula 1 it didn’t buy just one team, it bought two. The company owns or sponsors four professional soccer teams, including the New York Red Bulls, and runs a host of adventure sports events. And, in October 2012, Red Bull sponsored Felix Baumgartner’s skydive from the edge of space, during which he became the first human to break the sound barrier without a plane or rocket ship.

So when Red Bull wanted to find a way to push its athletes further and for longer, it didn’t just drag them into the gym or the performance lab, it took them to the lowest place in North America, Death Valley, and the highest city in California, Mammoth Lakes. And invited along a gang of academics and fitness tech innovators to push them and probe them.

Let’s be clear, little of this seems to be specifically about selling a caffeinated, sugary energy drink. From a marketing perspective, owning two F1 teams offers little value—even if one of them wins, the other loses. And a makeshift laboratory run out of the back of a white truck parked alongside US 395 northwest of Bishop, Calif., in late May was about as far from an obvious marketing opportunity as you could get. Sure, the awning of the attached canopy was adorned with Red Bull logos, and there was a limitless supply of Red Bull, but there were no adoring fans in sight, no media other than me.

This was Year 3 of Red Bull’s endurance camp, a scientific experiment in exercise physiology with six pro athletes as guinea pigs. “Every time it’s sort of this love-hate thing,” says endurance mountain biker Rebecca Rusch, the only athlete to have come to all three camps. “The information’s super interesting to me. Getting to talk to the top neuroscientists or the top cardiologists—all that is super fascinating to me not just for my own performance, but also because I’m just interested in it and it’s cool. But I know the camp always hurts a lot. They really push us to the ultimate limit.

“They’re essentially trying to break us down and see what happens.”

The first year was a little bit of an experiment in experimentation. Though the scientific aim was to investigate central fatigue, to see how the perception of tiredness correlated to real performance, manager Per Lundstam and the rest of his team also wanted simply to play with technology and athletes out in the field. “As soon as you take them into the lab you change their behavior,” says physiologist Dan Turner. “If we can keep them in their environment they have the same behavior patterns.”

Year 2 featured a return to the same problem of fatigue, but with a couple of twists. One was comparing the difference between central fatigue and the real fatigue in each muscle, and the other was using magnetic fields to stimulate nerve cells in the brain to see whether that could override central fatigue and help the athletes train longer. And, in the third year, the main focus was muscle activation, trying to understand how both altitude and the cadence, or pedaling rate, of the athletes affect their ability to engage the fibers in their muscles.

Hooked up to an array of medical and fitness technology, each athlete was sent out on a cycling time trial course in the hills northwest of Bishop. They had blood glucose monitors attached to their stomachs, heart rate recording band aids stuck to their chests, muscle oxygenation sensors strapped to their legs and wore shorts that could measure the engagement of the muscle fibers in their quads and hamstrings. Wires taped to each athlete’s neck and body fed to a device called PhysioFlow that could measure the amount and rate of blood flowing through each part of their heart. And before and after the time trials everyone had MuscleSound ultrasound scans to measure the amount of glycogen stored in their muscles.

The six guinea pigs were Rusch, triathletes Holly Lawrence, Angela Naeth, and Jesse Thomas, ex-pro cyclist David Zabriskie, and BMX racer Mike Day. “One of our biggest advantages,” Lundstam says, “is that we have such a vast variety of athletes from different fields and different disciplines.”

Day was the lone exception to the endurance theme because his BMX races last less than a minute. “I don’t come from this discipline,” Day explained, midway through the camp, “so for me I’m always learning the whole time.” This was his second camp, however, so he knew long ago what he’d signed up for.

“It’s cool to see Mike suffer through this,” Zabriskie joked. Used to the grueling three-week grind of the Tour de France, Zabriskie wasn’t exactly fazed by 10-kilometer time trials and indoor bike tests.

“I come here and I have no idea what I’m doing half the time,” Day said. “I’m just redlining the whole time, sweating, hurting.”

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After the first set of time trials in Bishop, the athletes relocated to Stovepipe Wells, in Death Valley, 10 feet above sea level, where the scientists converted a conference room into a performance lab. The next morning, following blood and urine tests, the athletes were kitted out with biometric sensors again, then put through their paces on stationary bikes. One-by-one they were subjected to a ramp test, increasing the power by 40 watts every four minutes while having readings taken and their fingers pricked to measure blood lactate, and then a max power test, trying to hold their absolute maximum effort for three minutes.

Once the first three (Rusch, Day, and Naeth) were done, they were driven across the road to a rocky airstrip and loaded into a Cessna Centurion for the journey up to the Mammoth Mountain Inn, 9,000 feet above sea level. Lundstam and his team simply wanted to test the affect of a rapid change in altitude on the athletes, but for Day a bumpy 40-minute flight over rocky ridges in a single-engine plane was the worst part of the whole camp. He wasn’t a huge fan of the wings Red Bull had given him that day, and was drenched in sweat as the plane touched down in Mammoth Lakes.

Up in the mountains, in another makeshift performance lab, the morning tests were repeated all over again, the athletes struggling to match previous scores in the thin air. Circled around the stationary bike, the scientists whispered to each other and passed along messages. One of the cruelest parts of the experiment seemed to be hiding how much time each athlete had left from them during the max power test.

“There’s always this interesting paradigm between their perception of their physiological state, and how they actually are,” Turner explains.

“Your brain,” Rusch says, “it’s your biggest enemy or your biggest strength, really. When do you quit and when do you not.”

In her high altitude max power test, Rusch’s brain quit on her. “I gotta stop,” she said a few seconds short of the three-minute target. “I’m sorry, I’m sorry.”

“You did great,” Craig Broeder, one of the sports medicine researchers, said.

“No I didn’t,” Rusch hit back, exhausted. “I’m sorry. I was so dizzy.”

As her breath came back, so did her competitive drive, and her frustration at not finishing the protocol spilled over. “I quit the test. Don’t tell me I did a good job when I didn’t,” she snapped. Even though she’d only recently recovered from a tropical parasite infection picked up in South East Asia, Rusch refused to let herself use any excuses.

​The next day they were back in Bishop for another time trial, then up to Mammoth again for more indoor tests the day after, before one final time trial in Bishop on the last day. Finally, exhausted, home to Los Angeles, Las Vegas, Oregon, and Idaho, and back to their real jobs of training and racing.

The main outcome for the six test subjects will be an athletic portrait of their bodies’ strengths and weaknesses, and personalized guidelines for training. Others within Red Bull should benefit, too. Even though this wasn’t a huge marketing opportunity in and of itself, having more Red Bull athletes on podiums around the world might be.

But first Lundstam and his team need to break down and dissect the data—roughly eight billion data points—at headquarters in Santa Monica. “We have to get our heads around that and see where it all ends up,” Lundstam says.

The group, though, was already excited by initial results. Getting a close-up look at a Tour de France veteran had both the scientists and the other athletes buzzing. Zabriskie seemed to have an unconscious physiological ability to hit targets and stay there as long as needed. “David’s been almost like a little spark, he’s given everybody a little bit of energy,” Turner said. “And people really enjoy it. They like to see the way he rides and the way he approaches the exercise tests.”

Thomas picked up some useful knowledge about himself, too. “When I’m on the bike, my left hamstring is firing at 50% of my right hamstring,” he says, “and I have a bunch of left hamstring problems, so there might be something neurological there where I’m literally not sending the same signal.” If he can work out why, and train to balance out the power from side to side, maybe he’ll win more races.

For all the questions this year’s project might have answered, though, as always, it raises many more. Red Bull’s high-performance group is already thinking about what’s next, because the ultimate goal of all this isn’t just to understand fatigue or muscle activation, but, as Lundstam says, “to unlock your own view of what is possible.”

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