Blog

How much stress is the right amount to enhance competition performance?

Share
.

As a Biological Psychologist, I am very much interested in the physiology of behaviour.

Looking at the World Cup, one stand-out point for me, after the England v Wales game, was the sharp form of Marcus Rashford (England). Human beings are intelligent and capable animals, and our greatest burden can often be to think ahead. We can have a full stomach and fear where our next meal is coming from. We can go to work and fear losing our job next month. This is the basis of anxiety, our anticipation of a difficult and unpredictable situation to come. Yet studies show that when the individual is confident of success, they see the incoming task to be less threatening and less challenging.

Lecturing on stress, I constantly talk of the difference between mild/moderate stress and more severe stress. The former is vital to success, and as stress can be positive, mild stress represents those moments when we are interested, excited, and enjoying the challenge faced.

For example, athletes achieve personal bests in competition, and not in practice. That extra level of challenge is key. But what is the physiology of being ‘in the zone’. Why is this good? Why is some stress vital, but too much leads to performance catastrophe?

The secret lies in an area of the brain known as the Ventrolateral Prefrontal Cortex, or ‘VLPFC’ for short. To be ‘ventral’ is to be beneath, and to be ‘lateral’ is to be to the sides (e.g. your ears are lateral to your face). So the VPFC is an area of the brain towards the front, but slightly underneath and to the sides.

Okay, but what does it do? Simply, it has lots and lots of norepinephrine receptors, with norepinephrine (also called noradrenaline) being a chemical that increases arousal, promotes vigilance and elsewhere in the body, it also increases heart rate, blood flow and the release of sugars from storage.

All well and good, but we also need to know that there are two types of norepinephrine receptors.

We’ll start with the α2-norepinephrine receptors. These have a high affinity to norepinephrine – meaning that norepinephrine wants to bind to them – and they also promote better performance. When norepinephrine binds to α2 receptors, it encourages that neuron to fire more frequently. Although it’s more nuanced than I’m describing, this can dramatically improve performance.

Now onto α1-norepinephrine receptors. These have a low affinity to norepinephrine – norepinephrine will bind to the α1 receptors, but only if no α2 receptors are available. If norepinephrine binds to α1 receptors, the effect of much more inhibitory, and performance nosedives.

When facing a mild stressor, some norepinephrine is released towards the top of the brainstem. It will make its way to the VLPFC and all those norepinephrine receptors. When it arrives, it has a choice of binding to high-affinity or low-affinity norepinephrine receptors. In such a circumstance, it will bind with the high-affinity α2s, resulting in improved performance.

Things continue to kick up a gear. The stressor continues, the threat/challenge continues to rise. More norepinephrine pours into the VLPFC and it will continue to bind with the α2s. Although at some physiological cost, performance is maintained.

But what happens when things continue to go pear-shaped? More and more norepinephrine is released, and more and more arrives at the VLPFC looking to bind with its favourite α2 receptors. But there are none left! So instead, grudgingly, norepinephrine starts to bind with the α1 receptors, and the whole area starts to shut down. The VLPFC has a role to play in motor function and in updating action plans. As a footballer, if you are here, you fall out of the zone, and then some.

So where does Marcus Rashford come in? As we saw in the tournament, we have a footballer who seems brimming with confidence on the world stage. For him, as a professional sportsman, this World Cup was a challenge to be faced and overcome. There is huge pressure on all the players in the tournament, but when you are confident and raring to go, there’s excitement, but no threat.

When he’s on the pitch in this mindset, there’s enough norepinephrine to put him ‘in the zone’ but not enough to push beyond and start activating those α1 receptors. And confidence like that is catching. Here’s to the next one!

Dr James Jackson is a Reader in Psychology at Leeds Trinity University, with research interests that include coping with tinnitus, chronic pain, and stress.

Leeds Trinity University's Corporate Communications team is the first point of contact for local, national and international media.

Looking to source a comment or would like to arrange an interview with one of our academic experts? Contact the team on +44 (0) 113 283 7100 or email the Communications team.

More about the Press Office
r