Taking a business from an idea to a product requires mental stamina. If your mind isn't alert, you miss opportunities, if you get mentally exhausted, you crash and burn.

To win the long run, an entrepreneur's mind must perform like an elite athlete. It must move at the right pace, with just the right amount of drive.

What is optimal mental performance?

Many people perform better under some pressure or "stress." But in most cases, what we call stress is actually "arousal," a psychological measure of alertness.

When arousal is too low, mental performance is sluggish. Performance improves as arousal increases, until a point where mental performance is optimal.

Increasing arousal beyond this point overwhelms the brain's attentional resources with stimulation. You're now so alert that your brain's attention is grabbed by distractions it would normally not notice.

If your arousal level stays raised, your brain eventually runs out of "stamina," your mental performance crashes and burns, and you descend into stress.

What happens in the brain during optimal mental performance?

A precise region in the brain called the Locus Coeruleus, or LC, is central to arousal. Researchers at Cape Town University think that when arousal is optimal, brain cells in this region fire at a precise rate. If they fire faster or slower, arousal is no longer optimal.

The key to optimal mental performance lies in learning how to keep arousal in its optimal zone, by increasing arousal when it is low and pressing on the brakes before it gets too high.  

If you're feeling sluggish, sleepy or bored, you'll want to raise arousal. Here's how:

1. Caffeine.

Coffee boosts arousal. If you want to stay in an optimal arousal zone, timing is key.

At excessively high arousal levels, your signal-to-noise ratio drops when you're trying to focus. So, if you use coffee when you are tired and "wired," you'll feel more awake and alert, but you'll also be distracted more easily.

To make the best use of coffee's effects, use it when you are tired and relaxed.

2. Exercise.

Exercise has a "Goldilocks zone" with mental performance; too little has no effect whereas too much can push arousal beyond the optimal zone.

Everyone's Goldilocks zone will be different, but one study suggests steady-state exercise may be better for reaching your optimal zone of arousal than short-duration, fatiguing exercise.

3. Challenge.

Anything that feels exciting, fun or challenging raises arousal. The challenge must not be too easy, nor too difficult. You should be able to meet it by stretching your skill set.

If you work at the upper limit of your skills, you stretch this limit as you reach for a goal.  Every stretch makes you incrementally better. This increases motivation. Motivation, in turn, increases arousal.

On the flip side, when you're feeling edgy, anxious, or "wired," you'll want to lower arousal. Here's how to do that:

1. Increase your sense of control.

When you're in control of what's around you, your immediate future becomes predictable and you don't have to stay anxious for threats, so your arousal level can climb back down.

Stress collaborates with high arousal to trigger anxiety and increasing perceived control can reduce features of anxiety.

Receiving regular positive feedback also enhances your sense of control over what you're doing.

2. Breathe.

Exciting new research has revealed a "highway" of nerves connecting the part of the brain that sets the rhythm for breathing to the LC.

In theory, this implies you might be able to modify arousal by controlling how you breathe, so if it rises too high, breathing slowly might be able to bring its level down.

3. Train your mind.

You're more likely to be distracted by negative thoughts if your arousal is too high. Dwelling on negative thoughts can, in turn, raise your arousal level even higher.

Focused Attention Meditation (FAM) has been shown to improve sustained attention. Practicing FAM can help you get better at redirecting your attention away from distracting negative thoughts and regulate emotion reactivity.

In my book Stress-Proof, I describe a FAM exercise that you can practice at your desk every morning, where you focus your attention on your coffee mug for 2 minutes, while repeatedly pushing away distracting thoughts.

Raise and lower the volume at the same time: Matcha

If you need that caffeine kick, but don't want to push arousal beyond its optimal zone, swap your coffee for the Japanese tea drink Matcha.

Matcha leaves contain both caffeine and an amino acid called L-theanine, which counteracts some of the increase in arousal caused by caffeine, so you feel more alert without being more prone to distractions. Meditating Japanese Zen Buddhist monks have long known this trick.

One of the most obvious indicators of arousal is the size of the pupils of your eyes. When your arousal levels dwindle and you start feeling bored, your pupils tend to shrink in size.

If you're leading a team of enthusiastic employees, be sure to look into their eyes. If their large, tonically dilated pupils at the start of the project quickly shrink, they may fast be becoming bored -- or completely exhausted. 

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