Is Stress Ruining Your Performance?


Many things can cause detrimental effects to your physical performance and ability. We all know nutrition plays a huge part in being healthy, being able to perform in your chosen sports and in the gym, as does your training. However, there is one thing above all else that is often overlooked when it comes physical performance, stress. That’s right, your stress levels may be slowing your recovery, sapping your strength, limiting your gains and causing you to gain weight.

I will explain what can cause stress, how it affects your physical performance and some resources to help.

Personally, I love CrossFit. It’s not for everyone but I love the way it pushes you to your limit and forces you to be better. One thing I have noticed looking at the top level athletes in CrossFit is pretty much all of them have amazing attitudes! They all seem like genuine, happy, laid-back people in their day-to-day life and this is actually a big reason why they are able to perform so well in the gym.

Stress can be caused by both physical and psychological factors like a tight deadline at work, noise, lack of sleep, illness, worrying and a thousand other reasons.

How does stress affect your physical performance?

When we become stressed, even if it is from a thought or worry, our body goes into fight or flight mode, which diverts the body’s energy from its normal maintenance, repairing, cleansing and rejuvenating mechanisms.[1] This is ok when we are in the mist of an intense workout but we don’t want this to happen all of the time or your ability to recover is severely hampered.

Your body responds to stress with a series of physiological changes including increased heart rate, elevation of blood pressure, secretion of stress/adrenal hormones: epinephrine, norepinephrine and cortisol (we will talk more about those hormones later).[2] Stress also causes increased muscle tension which will decrease mobility and the ability of a muscle to contract, lowering potential power output.[3]

Many of the symptoms associated with stress are due to the production of adrenal hormones. One of those is epinephrine (aka adrenaline), which causes the increased metabolism of protein, fats and carbohydrates. This isn’t good for athletes because it causes the body to excrete amino acids (building blocks of proteins) and essential minerals. Not only does the body excrete needed nutrients under stress but it has also been shown that there is an impaired ability to absorb nutrients as well.[2] Persistent stress can also lead to gastrointestinal distress (gas, bloating, pain, diarrhea) – please note these symptoms are not normal nor is any pain/issues with digestion, if you experience any please message us or talk to another knowledgeable individual about the subject. Once any kind of gastrointestinal issue arises it paves the way to other nutrient deficient disorders.[4] All of this will decrease energy, physical performance and recovery time.

Growth hormone is a potent anti-aging, anabolic and muscle building hormone. Another hormone, IGF-1 is stimulated by growth hormone. Both of these hormones increase amino acid transport to muscle, protein synthesis and glucose transport. This means faster recovery, more muscle building capability and more energy for your muscles to use.[5] As an athlete you need your body to be producing these hormones and guess what decreases them? That’s right, too much stress.

Another stress hormone we haven’t talked about yet is cortisol. It is released in response to physical and emotional stress. We need cortisol to live and survive however the issue is when we have too much cortisol. It has been shown to inhibit fat breakdown (can make you gain weight) and suppress your immunity – it’s hard to train when you’re sick.

Then there is testosterone: Both men and women produce testosterone, it helps to increase libido, allows for muscle repair and recovery, keeps you young, protects your heart and can increase your competitive drive.[6]

We ideally are looking for a high testosterone to cortisol ratio as it correlates very well with an increase in physical performance. Having too much cortisol from lifestyle and physical stress will lower this ratio which will lower your ability to recover since cortisol encourages breakdown in the body. Once again we need some cortisol to help us deal with stress and to encourage performance adaptations but the key is not overloading yourself.

How to increase performance:

– Try to nasal breathe as much as possible during during the day but also during exercise. When you nasal breathe during exercise you produce fewer stress hormones. Practice this with your warm-up and try to integrate it while the intensity increases. If you want to learn more about this, check out this interview with Dr. John Douillard a expert in breathing and exercise.

– Manage stress!!! Lifestyle stress for the majority of people is the biggest stress in their lives. There are different tools you can use to help manage stress:

– Practice mindfulness 

– Use positive affirmations 

– Use a gratitude journal (The 5-minute journal has worked great for me)

– Always look for the positives in life and situations

– Get enough sleep! Sleep increases growth hormone, testosterone and helps to manage stress

– Avoid excessive calorie restriction – will severely stress your body, cause a drop in GH, IGF-1 and testosterone

– Don’t train too much, listen to your body and take a break when needed

– Practice deep breathing

– Most stress is caused by situations or worries we mentally create. If this happens and you feel over-whelmed ask yourself “Do I have any problems at this exact moment” most of the time the answer is no.

– Avoid caffeine, alcohol, drugs and processed food as they will all cause excess stress on your body.

Manage your stress and watch your performance increase!

If you have any questions please feel free to let us know by email

Thank you for reading,



  1. Patrick Holford. The Optimum Nutrition Bible.
  2. Phyllis Balch. Prescription for Nutritional Health
  3. Phil Page
  4. Dan Benardot. Advanced Sports Nutrition, Second Edition
  5. David Clemmons
  6. Ben Greenfield. Beyond Training