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What Is Overtraining & What Are The Signs And Symptoms?

Overtraining can have a serious impact on an athlete’s performance. So what are the signs and how do you avoid overtraining?

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October 30, 2020

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Overtraining is a state in which the body does not have enough time to recover in-between sessions, and therefore develops fatigue and experiences a plateau in performance. More commonly, this is referenced as under recovering, as often the problem does not lie with the amount of training, but instead with the amount of recovery time given.


There are a number of signs that can indicate someone may be overtraining, some far more serious than others. Some are also far more obvious than others and will present themselves as external indicators whereas others may require testing or medical attention to bring to the surface.

The most common overtraining symptoms are:

  • Fatigue (physical and mental)

  • Plateau/decrease in performance

  • Lack of motivation

  • Reduced speed of recovery

  • Weak immune system (regular illness/infection)

  • Higher heart rate than usual


Overtraining can cause far more damage than initially thought. It’s not just physical damage (bone breaks, muscle tears, ligament damage) that can present themselves as a result of overtraining, the impact can go far deeper. For females, in particular, it can cause a number of hormonal issues, and can severely disrupt the menstrual cycle. This is more commonly known as RED-S. The body will always prioritise movement, meaning biological functions get pushed down the priority ranking and become neglected. Often, these signs are overlooked, and can later cause long term repercussions.

The more obvious impact is low mood, low sex drive and lack of motivation. All of these can present themselves quite early on and can be incredibly unpleasant for the individual to experience. These are often cases of extreme fatigue but can result in being detrimental to the athlete’s performance and mindset.


By keeping a watchful eye on key biomarkers, it is possible to observe any stress to the body that could be detrimental to performance, as well as ensuring optimal recovery throughout this and subsequent training blocks. There are a number of biomarkers that can be tested to better understand the impact of overtraining, and why athletes may be struggling with recovering from said high volume.


We look at haemoglobin, ferritin (iron stores) and transferrin saturation, which helps to identify absorption of iron from the gut. It is important to identify low levels as a deficiency will have a negative impact on appetite, energy levels and overall performance. It is important to look at all three values for the full picture; values of Hb should be 14 or above; ferritin 40 or above and transferrin saturation above 20% in individuals who are very active. If an athlete is overtraining, these biomarkers are likely to take a huge hit and low levels can cause much bigger issues.


We know from studies that low levels are very common in the UK due to the lack of sunlight. Deficiency in the general population has been linked to low immunity, low mood, and fatigue. This is further enhanced in those of us that are very active also resulting in poor recovery between training sessions, and increased muscle soreness. vitamin D has a very important role in bone health as it helps the absorption of calcium. Acceptable levels of vitamin D for the athletic population should ideally be > 90nmol/L. If these levels are low, they could be directly impacting the athlete’s rate of recovery, which in turn could lead to greater fatigue, a sign of ‘overtraining’.


The thyroid gland is integral to our health and performance on so many levels. These levels are of particular interest to us when monitoring runners and endurance athletes. We will look at TSH, Free T3, LH, oestrogen, and testosterone.

When we overreach, over train, and/or under fuel, we create more stress to the body and in some cases, this can result in RED-S. The stress has a negative impact on the pituitary gland and thus can dial down our thyroid function. Monitoring TSH can help identify those at risk while looking at T3 which if low will indicate low energy availability, showing that there is not sufficient energy being taken on board to fuel both the training and maintain biological processes. This, in turn, can lead to a reduction in the production of sex hormones. Chronically low oestrogen and testosterone levels will have implications on bone, cardiovascular, and immune health as well as overall mood, all of which can contribute to high levels of fatigue.


These biomarkers give us direct information about the level of inflammation in the body.

While exercise will result in raised levels, testing these can be a good indicator of recovery rates after races whilst also providing a relative risk of overtraining. This is definitely something we look at when a runner is looking to go back to training after racing. Training with raised levels will increase the risk of injury but also overall stress on the body and potentially bring signs of overtraining to the surface, which can result in fatigue and decreased performance.


While levels of cortisol will be highest in the morning, consistently high cortisol levels indicate the body is under stress; this could be due to a lack of recovery, poor sleep, high anxiety levels, or poor fuelling. Regardless of the cause, chronically high levels will have negative consequences on immune and metabolic health.

Additionally, there will be a dysfunction in fat and carbohydrate metabolism which can result in the body preserving energy and holding onto visceral fat; this is why in some cases, the harder the individual works, the more stress they create but there is no adaptation with regards to body composition or performance.


Edge tests can be personalised to the individual to produce results on key biomarkers that may be affecting their performance. Our tests are incredibly easy to do at home, and athletes can expect results within 3 days to allow athletes to pick on potential signs quickly and react. It’s important to understand that tracking over time is the best way to understand your own personal levels, for example, your normal levels may sit a little lower or higher than the average. Any changes to this ‘norm’ are what you need to stay on top of to help prevent overtraining.


Overtraining recovery plans will be different for each individual, based on the biomarker test results. As mentioned, it’s most likely overtraining is a result of neglecting recovery or diet, so most cases will simply require a slight shift in nutrition and/or lifestyle to help bring the athlete back to a recovered state.


Overtraining is commonly diagnosed, especially in the endurance world. It’s often a case of athletes/individual’s not respecting the demands of their sport(s) on the body and becoming impatient with the time it takes to properly recover. Experience and education are the best ways to overcome overtraining, as it allows the individual to gain a greater understanding of what their body needs to prevent this from happening again. Our blood tests help with this by offering you intelligent, informative data to help keep your body in a balanced state.