(Inside Science) -- In late May, about 6,000 researchers met in Orlando, Florida for the annual meeting of the American College of Sports Medicine. They discussed all kinds of topics from genetics to marathon performance to sports science in the performing arts. This is the third installment in a series of stories about the ways researchers are studying sports and things that would seem not to apply to sports at all.
One topic that I didn't expect to encounter at the conference was motor sports. But it makes perfect sense that the riders in motocross events, who zip around dirt tracks aboard motorcycles, making hard turns and high jumps while enveloped in safety gear would qualify as athletes.
And NASCAR pit crew team members? The ones who jack up the cars and change the tires? Yes, they are athletes, too.
Tim Lightfoot, an exercise physiologist at Texas A&M University in College Station, told me about one NASCAR team, Hendrick Motorsports, which began hiring big and powerful athletes in the 1990s in an attempt to shave precious seconds off the length of pit stops during races. It triggered a giant shift in how pit crews were formed across the sport.
Nowadays, he said, the teams are recruiting college athletes that didn't make the pro ranks in their original sport, but could apply their athleticism on "pit road" – the pit crew’s playing field.
"For example, football players -- linebackers, tight ends…those are the kinds of folks they go after," said Lightfoot.
In fact, there are certain dimensions and athletic attributes preferred for the people in different pit crew positions, just as in football or basketball.
"It's very position specific," said Lightfoot. "For folks who change the tires, they need people who have a somewhat lower center of gravity. Which means that they're usually a little bit shorter than the average individual, which means they can get down and get up very quickly, and that have really quick hand eye coordination. For the jack men they need somebody who's big and brawny who can like pick up a car with one pump of the jack."
The same athletes would probably struggle to be elite motocross riders. A rider's physique may look similar to any relatively thin and fit individual. But according to research also presented at the meeting, the best riders have extraordinary strength and endurance, especially in their forearms and thighs.
Michael Ormsbee, from Florida State University in Tallahassee, is an expert on the elements of human performance and nutrition as applied to sports and everyday life. Soon after connecting with Clint Friesen, who was the performance director at a motocross center called the Millsaps Training Facility in Cairo, Georgia, they began a new project. The two teamed up to study motocross athletes-- a group they say has been almost completely ignored in sports performance research.
The research began at a pretty basic level.
"[No other research] really looked at just characterizing who the athlete was, which is where we needed to start,"' said Ormsbee. "We took [Friesen's] elite people and compared them to college-aged guys. They were fit people. They could be gym goers, or people who exercised, but we wanted to see in that classic model of a college student, how does that compare to the most elite riders? Can we pick out any characteristics that make somebody good?"
One simple exercise where motocross riders excel is called a wall sit. It's a straightforward exercise -- just lean back against a wall, and slide down until your knees bend 90 degrees. Holding the position is easy at first. But as the seconds tick away, your thighs begin to burn. Motocross athletes, the researchers found, had no problem with wall sits.
"If you've never done one, it'd be hard to make it to a minute," said Ormsbee. "And some of these [riders] were just holding it forever."
The riders had very similar results on a number of other variables that the team measured, including body composition, muscle mass and fat distribution. But, one other attribute really stuck out.
"The other thing these guys had was a hold -- a forearm strength -- because they have to hold that motorcycle as they're going around," said Ormsbee.
The results highlighted that going faster on a dirt bike is not as simple as opening up the throttle a little more.
"You have all these g-forces from acceleration, deceleration, acceleration, jumping and turning," said Friesen. "The sport's gaining popularity because people like to watch guys fly through the air and whatever, but in terms of really validating it as a sport, the fitness matters."
And it is not only their fitness that is tested. For these athletes, beating the heat while covered in protective equipment can be a significant challenge. It's one of the areas that Ormsbee and Friesen plan to tackle next.
Ormsbee said that in his lab, they are monitoring cyclists inside heat chambers and placing probes in their skin, fat, and muscle to figure out how the body might use different fuel sources at different core temperatures -- for example, burning more carbohydrate or fat under different heat and exercise intensities.
"It's the hot temperatures that tax our athletes. They're covered from head to toe with helmets, goggles, boots, gear, everything. So there's not a piece of skin that's showing and exposed," said Friesen. "So the amount of sweat and dehydration is kind of interesting."
Ormsbee indicated that if the study reveals differences in the body under different conditions, they might be able to improve the nutrition and hydration plans for motocross athletes.