Sometimes writing comes fairly easily. Other times, I struggle: To find the right words, the right flow, to turn what feel like disconnected thoughts into something coherent.

But I don't just know I'm struggling. My body confirms it. My heart rate goes up. My body temperature goes up. I even start to sweat, even though I'm just sitting.

Weird, right?

Actually, no. According to this ESPN article

Robert Sapolsky, who studies stress in primates at Stanford University, says a chess player can burn up to 6,000 calories a day while playing in a tournament, three times what an average person consumes in a day.

Based on breathing rates (which triple during competition), blood pressure (which elevates) and muscle contractions before, during and after major tournaments, Sapolsky suggests that grandmasters' stress responses to chess are on par with what elite athletes experience.

Clearly I'm not suggesting that my mental effort -- or ability -- in any way approaches that of a grandmaster playing tournament chess. 

But the effect is the same. Constant mental stress naturally increases heart rate. Increased heart rate forces your body to produce more energy. Producing more energy requires more oxygen. The combination ramps up your metabolism... and boom: You burn a lot more calories.

Which Means Fitness Matters

While it's easy to assume that living a healthier life is a personal goal, health and fitness can play a major role in your professional success.

While the physical benefits obviously matter, the mental benefits of improved health and fitness are significant: Mental toughness, perseverance, determination...all are important ingredients for business success. (And all can be developed.) 

That's why Magnus Carlsen, the best player in the world, follows a strict workout regimen, travels with a personal chef, chews gum during games to increase brain energy (oddly enough, science says that works), and even spent considerable time determining the best way to sit: Lower back against the chair to maintain a natural curve, knees slightly apart, both feet firmly on the floor, body tilted forward at a 75-degree angle: 

The result? He sits far enough forward to stay alert, but not so far back that he places unnecessary strain on his neck and shoulders.

That's why most of the world's top players have adopted strict diet and fitness routines to help them concentrate better, concentrate longer... and withstand the mental and physical strain that results from long periods of concentration.

Especially When the Stakes Are High

But here's the thing. Concentration alone isn't enough to hyper-charge your metabolism.

You also have to care.

Take me. Say I spend twenty minutes trying to learn a little Spanish. No matter how hard I concentrate, my heart rate won't go up, my respiratory rate won't increase, and I definitely won't start to sweat.

Because while I'm trying, nothing is really at stake.

But if you and I have thirty minutes to learn a list of words... I'll probably be a sweaty mess after the thirty minutes are up. 

I hate to lose. So yeah, I'll be into it. Even though I'll just be sitting in a chair I'll "work" my butt off to learn those words.

High Stakes = Extreme Concentration = Success (and Growth)

So if you're looking for a way to take yourself and your business to a higher level, make sure you reap the benefits of health and fitness.

Eat healthier. Add a little cardio to your day. Add a little strength training to your day.

See it not just as "fitness" training, but also as a way to sharpen your mental edge -- and to sustain that edge by overcoming the fatigue that naturally creeps in after long days of making difficult decisions.

And also keep this in mind: If you're at work and your heart rate never increases, if your respiratory rate never increases, if you don't occasionally break a sweat due to mental exertion... don't assume you're just great at managing stress.

You might not be "working" as hard as you think -- or, more likely, the stakes might not be as high as you think.

Which means you aren't taking very many chances. You aren't taking very many risks.

You aren't pushing yourself into the discomfort zone, and you can't have that.

Because making yourself uncomfortable also makes you grow, both professionally and personally.

And also might help you lose a little weight.

Can't beat that.