Understanding the Science of Redox in the High Performance Environment

Hearing phrases like ‘GO HARD OR GO HOME!’ and ‘NO PAIN, NO GAIN!’ should be consigned to history. But how much is too much? At what point does the risk of illness, injury and underperformance take over?

The smart approach is to use data to understand exactly when this point might have been reached. We caught up with one of our lead scientists Dr Nathan Lewis on the subject of redox monitoring as an approach for identifying appropriate training limits for athletes.

Nathan is a Clinical and Performance Nutrition Scientist and registered Dietician, actively researching redox homeostasis in elite athletes. He has worked with Orreco athletes since the company’s inception and has advised Great Britain Olympic athletes across four Olympic cycles. In this blog, he explains briefly the science of Redox Homeostasis and the benefit to the athlete of regular monitoring of redox

What does redox mean?
I’ll go into this in more detail later, but in simple terms REDOX refers to chemical reactions known as REDuction and OXidation reactions. Exercise is known to increase redox reactions. This isn’t inherently ‘bad’. In fact, redox is a necessary part of improving in our sport (i.e. physiological adaptation).

Examples of environmental factors that increase redox reactions include pollution, lifestyle choices, dehydration, UVA, heat and especially stress.

The human body works to maintain a state of redox balance (homeostasis), primarily through the activity of antioxidant enzymes in the body. However, food-derived antioxidants (what we eat, how much of it, how often and its metabolism by the gut) also play a prominent role.

Why is redox important for athletes?
Elite athletes prepare their bodies for competition through repeated cycles of training and recovery. Many aspects of their daily routine from training, eating and sleeping will impact on redox status i.e. the production of RONS (reactive oxygen and nitrogen species), the intake of antioxidant nutrients, and the up regulation of various antioxidant and repair enzymes. One of the fundamental features of adaptation to training (aerobic, anaerobic, resistance, yoga, concurrent) is the production of RONS with the translation of redox genes and the accompanying synthesis of antioxidant enzymes and associated cytoprotective proteins.

However, too much training, or a gross imbalance between the stimulus (training load) and recovery (rest and diet), can significantly upset redox balance and push the athlete into a fatigued, maladapted state with underperformance. Such a state may result in injury if prolonged or the spike in RONS is considerable and significant overload occurs. That said, we do want to disrupt redox balance to drive adaptive changes in the athlete’s physiology, but finding the right amount of redox ‘stress’ and quantifying the athlete’s own individual redox ‘threshold’ is a serious scientific undertaking.

Is it useful for athletes to know about their redox status?
Tracking redox biomarkers to understand when an athlete has significantly disturbed redox status can really inform the training process by providing real time feedback to coaches and athletes. Indeed, we have developed such an approach which use with athletes and a number of our clients are placing great emphasis on our redox monitoring tool.

If you want to read more about the importance of redox and measuring redox in the athlete, a good place to begin is our recent case study of an elite rower diagnosed with unexplained underperformance syndrome. https://www.ncbi.nlm.nih.gov/pubmed/28422588

What situations can cause redox to be significantly altered?
Simply, ‘stress’ situations. This stress can come in various forms. For example, psychological stress, competition stress, dietary stress, heat stress, infection and trauma are all well recognised in altering redox. In addition, redox is significantly altered in disease states, whether these are chronic diseases reflective of poor lifestyle choices (e.g. cardiovascular disease, type 2 diabetes, obesity), or autoimmune inflammatory diseases. A well recognised condition in which redox can be grossly disturbed is chronic fatigue syndrome.

So can you tell us a bit more about redox reactions?
Redox reactions refer to the transfer of electrons between atoms and molecules (involving reactive oxygen and nitrogen species or RONS), which leads to one molecule in the reaction becoming reduced and another oxidized i.e. modified. For instance, when you cut open an apple and leave the flesh exposed to the air, it will turn brown over time. This is the process of oxidation. Air, specifically oxygen, will cause oxidation. Equally, we are aerobic organisms. We breathe air and burn fuels (foods) in the presence of oxygen. As a result, oxidation reactions occur continuously within the cells of our bodies. This is important in the context of training because, as I mentioned earlier, exercise is known to increase these redox reactions.

What do we need to know about RONS?
A simple way to understand RONS is to think about them as signals that transfer a message. For example, a signal produced in one part of the cell can be transferred to another part of the cell through changes in the concentrations of RONS. Again, RONS should not be viewed as ‘bad’ or as needing to be totally neutralized. We now know that RONS drive some of the adaptive responses to exercise and we need them to get better at our sport. We know this because using large doses of antioxidant vitamins blunts some of the benefits that come with aerobic and resistance training – so caution should be exercised with the use of vitamins. Foods, and the consumption of foods that contain antioxidants, on the other hand, do not blunt adaptation (at least we know of no scientific study to date that has demonstrated this in humans). And so a ‘Food first’ approach should always be advocated when it comes to antioxidants! Interestingly, we also know that if you remove antioxidant foods from the diet inflammation increases, as does oxidative stress and training tolerance is reduced.

How is redox managed and controlled?
Within the body there is an extensive network of antioxidants, referred to as exogenous nutrients obtained through our diets (e.g. plants and seed derived polyphenols and carotenoids, and antioxidant vitamins such as C and E), and endogenous enzymes produced within the body (e.g. enzymes being built from amino acids and trace elements). This antioxidant network of nutrients, enzymes and various proteins function to maintain a state of redox balance, essentially working to keep the production of RONS in check. It is important to note that the antioxidant enzymes are increased with exercise stress, an adaptive response.

When a significant imbalance occurs, what can be done to shift redox balance back towards a ‘normal’ status?
In order to shift redox balance in the desired direction, knowledge of the factors known to cause significant disturbances in redox homeostasis are required. Examples of countermeasures could include a reduction in athlete training load, changes to dietary patterns, sleep hygiene advice, and the management of psychological and social stressors.

How does redox monitoring benefit the athlete?
By regularly measuring redox we can provide real time objective biochemical insight into the physiological and psychological stress that the athlete is experiencing. We can monitor their tolerance to training load and deliver individualised strategies to help optimise periods of recovery and regeneration.

Orreco routinely measures redox status in elite and professional athletes as part of a broad biomarker analytics service.

For a selection of Nathan’s publications on Redox Homeostasis check out:

(2017) Alterations in redox homeostasis during recovery from unexplained underperformance syndrome in an elite international rower.

(2016) Effects of exercise on alterations in redox homeostasis in elite male and female endurance athletes using a clinical point-of-care test.

(2016) Critical difference and biological variation in biomarkers of oxidative stress and nutritional status in athletes.

(2015) Alterations in redox homeostasis in the elite endurance athlete.