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    Post exercise immunosuppression (PEIS) and endurance athletes

    Posted by Warren Pole, co-founder 33Shake on

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

    peis post exercise immunosuppression training

    Don't let your training and performance suffer because of illness - power up your immune function and smash year-round performance with our guide

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

    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?

    Know your enemy - Post Exercise Immunosuppression (PEIS)

    The problem is Post Exercise Immunosuppression (PEIS), also known as exercise induced immunosuppression.

    Ignore the name changes, they're the same thing and happen when exercise increases levels of the stress hormones adrenalin and cortisol in the body. 

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

    peis post exercise immunosuppression kitten

    You, with PEIS

    Avoiding post exercise immunosuppression - 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”.

    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 post exercise immunosuppression

    peis post exercise immunosuppression battle ropes

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

    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. 

    “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. 

    “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. 

    post exercise immunosuppression peis vegetables

    Go big on the veg - the more different colours the better - for great antioxidant and alkalysing benefits

    Increased acidity utterly knackers your immune system.

    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. 

    This is where our Pre and Post Workout Shakes pack a killer PEIS punch. Packed with the 33 most powerful athletic superfoods in nature these are your ultimate insurance against illness on race day and during those toughest training blocks building up to your race. 

    33Shake pre and post workout shake peis

    Add our gamechanging Pre & Post Workout Shakes to a good daily diet and say hello to upgraded performance and support for your toughest training and racing. All with no other supplements needed

    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 PEIS: 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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