Does Strenuous Exercise Compromise Immunity?

A recent talk with a group of friends raised the question of just how compromised our immune systems are, doing hours of strenuous exercise each week.

What about the health benefits from a physical and mental standpoint? And all the research that gets cited when it comes to stress?

If you’re not an athlete, should the answer be, “it doesn’t matter?”

Let’s dive in and see how strenuous exercise can help or hinder our immune system.

What defines “strenuous exercise”?

As a group of “mature” individuals, most of the group quickly identified we use exercise as an outlet for the stresses of the working week and are not high-performance athletes [and] military personnel.

A training session that might barely qualify as a recovery day for one but severely tax a less well-trained individual is a balance only that person will know.

So saying that a training load of X is damaging is non-specific and

What about immunity then?

One of the great analogies raised was the idea of playing a game of Jenga. You pull away the plastic pile guide. One by one, you pull out blocks and stack them on top; at some point, the tower falls.

When it does, which block is responsible? The top one, right?

Not really. The position of every block contributes to the instability of the tower. The last block was just the last straw.

Blaming the last block is the proverbial ‘straw that breaks the camel’s back’. We give one cause among many all the credit for the outcome.

The underpinning message here is that your immune system is a delicate balance of lots of individual pieces finely balanced.

Stress comes from many factors.

So what about stress, then? Is it not important to factor in this with compromised immunity?

As the discussion deepened, we realised that many of us still have the “strong-like-bull-smart-like-tractor” approach to training.

Most of us have kids, and we try to cram training into any time remaining throughout the day/week.

Unfortunately, this means we are all stupider than we are strong, and most of us get sick more than usual.

For most people, training is an optional add-on. But like a game of Jenga, training was just the top block in the pile. We realised that we would have much rather dialled-back life stress than dialled-back training. But we didn’t do either, so we all got sick.

The reality is that all of life’s stresses contribute, and at least twice a year in our group, these factors are significant to push us all over the edge. Our immunity isn’t just compromised because of our family situations but also the stress resulting from our approach to life.

If we can find balance, those stress factors will all start to taper off. Easier said than done right?

Questions you should be asking.

Rather than blame one factor, here’s your chance to ask yourself some of the questions we all should be asking:

1. How close do I run to the line to stay healthy?
2. How much bandwidth do I have for the training I need to reach my goals?
3. Can I decrease my baseline stress? and
4. Can I increase my breaking point? or
5. Should I accept the bandwidth that I have available and dial back my training instead?

What margins do you need to stay healthy?

At best, training is fudgy and imprecise, so it’s silly to try and come up with an exact amount of time or any other metric.

Instead, what works well is to never go to your limits in training and listen to your body.

HIIT aficionados will hate the thought of delayed gratification, but it’s much more sustainable in the long term.

To do so, always have one more hour or one more interval left in the tank. Do as much as necessary, not as much as possible. Otherwise, you’re grinding yourself down. You’ll get weaker over time and, eventually, sick.

Our total bandwidth is what’s between our baseline and our breaking point. Our baseline is the number of inescapable demands on us. Our breaking point is our mental and physical limits.

I think of stress as anything external, primarily work, people, and travel.

So what can we do to decrease vulnerability?

The primary factors are food, sleep, and attitude.

• Are you eating well? Is your diet nutritious and free of processed food and alcohol?
• Do you sleep at least eight hours per night? Can you take a nap in the afternoon?
• Can you improve your attitude in a practical way? Can you let go of what you can’t control?

And why doesn’t the effect on immunity matter?

Most importantly, whether strenuous activity compromises immunity or not, it doesn’t matter. You are a living, breathing Jenga tower impacted by hundreds of thousands of external factors above training.

Athletes would look at it in isolation if it were somehow proven that training had no effect on immunity. It would be “a get out of jail free card”. They would overtrain.

Only by looking at every factor can an athlete get a good idea of how much they can handle. And then, with the right dose of humility, we balance resources according to our capacity and priorities.