Post Exercise Immunosuppression (PEIS)

Post Exercise Immunosuppression (PEIS)

You’re in great shape, so why do you keep getting ill? You may be suffering from Post Exercise Immunosuppression (PEIS) where hard training knocks your immune system. Beat it with these three simple tips

The harder you train, the fitter you become. Sleep patterns improve, stress levels drop and you go about daily life with a spring in your step. Better still, you see your race times dropping. Life is peachy.

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But it isn’t always like this. Because despite being fitter than much of the population, many athletes still get sick more often than the average sofa surfing regular Joe. What gives?

What is Post Exercise Immunosuppression?

Post Exercise Immunosuppression (PEIS) - also known as exercise induced immunosuppression - occurs when exercise increases levels of the stress hormones adrenalin and cortisol in the body.

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This is a basic stress reaction and exactly the same as we experience under more traditional forms of stress like work pressure, difficult emotional situations or simply lack of quality sleep. This then knocks out your immune system temporarily, leaving you weak as a kitten when any colds or viruses come your way.

Avoiding PEIS - intensity matters

The level of exercise has to be high for PEIS to kick in. 

Moderate training won’t cause a problem - if anything this will boost immunity - but when sessions go over two hours or intensity regularly steps above 8/10 PEIS problems can occur. 

Endurance specialists like Ironman competitors, marathon and ultramarathon runners are especially at risk.

“PEIS is a genuine problem,” says Gareth Evans, sports scientist at the Porsche Human Performance Centre who deals with a number of elite endurance athletes. 

“It's linked to overtraining, and is made worse by people training through it”.

post exercise immunosuppression - 1

Good news - you can power past PEIS while also smashing all of your training goals

So PEIS is a real concern for anyone training hard, although there’s no need to suddenly wrap yourself in cotton wool to avoid it either – too far that way and you’ll only create a new set of problems.

“Stop training at the first hint of a sniffle and you’ll never reach your potential,” says triathlon coach Joe Beer. 

“You’re not doing triathlon if you don’t like a bit of discomfort – it’s about pushing yourself and seeing what you’re made of.”

How to train AND avoid PEIS

First, not all illness is caused by PEIS. Two colds a year is pretty normal, but if a pattern is developing where you’re consistently more ill than people around you or colds and bugs take forever to shake off, this is a big indicator PEIS is at work.

Important to know too that us age groupers and amateur athletes are often at more risk than pros - this is not a condition that only affects elites. 

While some experts sniff at the idea of anyone around the seven-hours-per-week training mark being able to overdo it, that’s because they’re looking at it from a pro perspective. 

Seven hours training in a week is nothing to a top athlete who will regularly clock 30-plus. 

The difference is this is all pros do - the rest of the time they're resting, eating or sleeping. 

Meanwhile back in the world the rest of us live in training is made to fit around already packed lives – full time jobs, kids to look after, and no coach to monitor it all for them, let alone an assistant to do the shopping and a chef to cook their meals.

“Elites have it easier,” says Beer. 

33fuel post exercise immunosuppression - stressful work

Trying to balance a stressful work life with hard training? You're a prime candidate for post exercise immunosuppression

“They can overdo it and then take a couple of rest days. But age groupers can’t. Many [amateurs] think a rest day means simply not training. It’s not. A rest day at pro level is doing absolutely nothing. Lying on the sofa all day, maybe having a massage. That’s a real rest day and they’re hard to come by when you have a job and a family”.

Beat post exercise immunosuppression 1: nutrition

The biggest solution for PEIS is the simplest - nutrition.

First you need a good, powerful, natural diet.

“With the immune system it’s all about getting a varied diet,” says Evans. 

33fuel post exercise immunosuppression - healthy food
Go big on the veg - the more different colours the better - for great antioxidant and alkalysing benefits

“We ask our athletes to self-monitor – everyone says they eat healthily, but when they keep a record of everything they eat we often find their diets aren’t as good as they think. A balanced wholefood diet is what’s needed”.

Beat post exercise immunosuppression 2: antioxidants & alkalysers

Next you need plenty of antioxidants to help fight off those bugs kind colleagues bring into work or fellow commuters sneeze around the tube on a Monday morning just when you’ve whacked yourself out training or racing all weekend.

Then you’ll want to alkalise your diet as much as possible. 

Fast foods, processed foods, baked goods, caffeine and high-sugar foods – the nutritional cornerstones of our time-poor lives – are all acid-forming and doing their worst to make our bodies more acidic than they should naturally be. 

Increased acidity utterly knackers your immune system.

post exercise immunosuppression - healthy greens

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There are many ways of boosting antioxidants and alkalysing foods in your diet - powering up on leafy greens and bright berries are both great and easy wins straight out of the gate. 

To take things to the next level, superfoods (simply any food with a higher than average concentration of beneficial nutrients) are the answer. Harnessing the power of incredible ingredients like chlorella, maca, reishi mushroom and spirulina can transform immune performance. 

Beat post exercise immunosuppression 3: hydration

The final nutritional tip is also super-simple, and it’s all about water. 

You need to stay hydrated, and do this with water - not sports drinks.

Mucus and saliva are two of the body’s very best natural barriers against infection but both perform badly when you’re dehydrated, so plenty of water during heavy exercise is key, even more so afterwards when your immune system could be at its lowest.

Beating post exercise immunosuppression: conclusion

  1. Eat a powerful fresh diet packed with whole foods
  2. Go big on antioxidants and alkalysers
  3. Hydrate well with water

Keep these three three in place and you’ll be in the strongest possible position to kick PEIS into touch. 

Train strong folks!

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