TAMPA - When breaking down the competitive skill in Saturday night's Monster Energy AMA Supercross Championship Series event at Raymond James Stadium, you won't find an analysis of 40-yard dash times, bench-press weights or vertical-leap measurements.
But make no mistake, by anyone's measure, these are not just daredevils who drive powerful machines.
These are athletes.
"I get that question a lot,'' said Supercross driver Justin Brayton, 33. "Some people think the only thing we do is turn our right wrist for the throttle.
"If you operate one of these motorcycles at the highest level of competition like we do, that means you're utilizing your heart rate to the max and you're using every muscle in your body.''
Last year, the Jacksonville Orthopedic Institute and Action Sports Medicine Foundation placed heart-rate monitors on Supercross riders and measured an average of 180 beats per minute (about 92 percent of their maximum heart rate). And that's from start to finish in a race, which runs in 20-minute intervals.
That's a greater stress rate than hockey (with line changes every minute or so), football (filled with short bursts) or basketball (where there's starting, stopping and substitutions).
"You almost have to go through it to understand the physicality of our sport, but it's really tough to hang onto that bike, which weighs about 240 pounds when you include the fuel and everything,'' said Supercross driver and Clearwater native Kyle Chisholm. "Do we just show up and drive? Hardly. We all go through a pretty rigorous regimen.''
It includes yoga, strength training and lots of cardio.
It includes running, swimming, rowing and stretching.
And it definitely includes nutrition.
"It's like trying to be a triathlete, but also having the strength to pull you out of situations,'' Brayton said. "I have experimented with a lot of diets, so I feel like I know what works well for me.
"I need to eat well. I'm probably 90 percent gluten free. That makes me feel so much better and I'm not bloated. I stay away from red meat and limit my sugars. It's tough because I have a sweet tooth, but if I stay disciplined with my diet, I definitely feel the advantage during the races. And you're looking for any edge you can get.''
That includes a mental edge.
When the drivers use speeds that approach 60 mph to navigate the artificial, man-made dirt track that fills the interior of Raymond James Stadium, when they execute hairpin turns around obstacles, when they take off for jumps of up to 70 feet (or the length of two school buses) and soar to the eye-level of fans in the club section (or a three-story building), another things becomes clear.
This looks awfully dangerous.
But nerve is another necessary skill.
"Anybody would look at this and say, 'Holy crap, that's crazy what they're doing out there,' but the truth is they know what they're doing,'' said Ricky Carmichael, a seven-time champion who is considered the best Supercross racer of all time. "They are in control. Of course, they are taking a risk. But they are so good and things are so competitive, it just becomes a focus on the racing.''
"It's not like we're going out there for the first time riding a dirt bike,'' Supercross driver Joey Savatgy said. "We have years of training and preparation. You wouldn't go play an NFL game if you never played football before. As for the risk, yes, there are always butterflies and the unknown. But that's how you know you're alive. Truly, this is what we live for.''
Brayton said he has an intellectual understanding of the danger in Supercross racing. On the other hand, it's never in the front of his mind.
"The biggest thing is timing,'' Brayton said. "The jumps are totally second nature. If you land 2 feet too short or 2 feet too longer, it's going to be a bad day. But when you feel completely ready, physically and mentally, you just do your thing.
"Do people around me worry? I'm sure they do. People say, 'Why do you do that? You have two kids.' Honestly, when I put my helmet on, that's when I feel the most safe. I'm comfortable and in my element. When you prepare your body and your mind, you just go out and perform. That's what athletes do.''
Contact Joey Johnston at hillsnews@tampabay.com.