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How Do You Know If You Are Recovered?

Training schedules often focus on the big long endurance days or the hard sessions, but what about recovery time? If you have multiple races during the season it’s crucial to factor in a few easy days or even weeks in order to keep performing at your best (and injury free!) throughout the racing season.

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August 13, 2021

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Recovery from exercise is the time between exercise and the return to a rested state. This could be anything between intervals during a hard run or actual rest days between sessions. It’s not just about this though, it also includes sleep, nutrition and lifestyle factors – all of which play into optimising your body for performance.

The recovery phase allows us to adapt to the stress associated with exercise, replenish muscle glycogen (energy stores) and provide time for the body tissue to repair. When training, several physical and psychological changes take place affecting your metabolism, peripheral and central nervous system, skeletal and muscular system, endocrine system, immune system, and cardiovascular system.


Recovery is something so many of us athletes struggle with, often driven by the ‘more is better’ motto. In reality, this is far from the truth.

Building adequate recovery time into your training schedule will help you meet your performance goals faster with a reduced risk of injury. Conversely, putting too much strain on your body through too much exercise and not enough rest will have a detrimental impact on your health and sports performance.

The consequences of this mean that many of the body’s systems are affected, such as metabolism, bone health, menstruation, immunity, mood, and cardiovascular health [1].

Signs of over-training and under recovering include:

  • low mood

  • catching colds and getting ill more frequently

  • poor sleep

  • irregular or no periods (women)

  • low libido

  • weak bones

  • muscle fatigue

Check out our previous blog on "Why Does Your Body Need Recovery Time?" for more on types of recovery, the importance of sleep and some top post-session recovery nutrition ideas from in-house dietician Renee McGregor.


Edge biomarker profiling tests, divide biomarkers into key performance categories. This helps you gain insight into how your body is performing, and how to optimise training load, recovery and nutrition.

So, what are the key recovery biomarkers our tests look at, and how can you improve your results to optimise recovery?

Cortisol (9am)

Cortisol is a steroid hormone responsible for the breakdown of fat and protein and stimulates the production of glucose in the liver. It is often referred to as the fight or flight hormone as it is key to stress response. When the body is under stress it releases cortisol causing our levels to rise. [2]

Under a normal sleep pattern cortisol release peaks when we wake up in the morning and reduces throughout the day. This is controlled by a section of the brain called the hypothalamus which is like the control centre of the body. Exercise and anxiety can cause an increase in cortisol levels in the blood which also leads to the release of glucose and fatty acid stores for energy. [3]

Lower intensity exercise doesn’t increase cortisol levels significantly. Hence varying intensity and ensuring rest between tough sessions is critical. [4]

When your cortisol levels are high, it is normal to have a change in mood i.e. feeling down, anxious or moody. You may also gain weight quickly which can affect your confidence and self-esteem. Other symptoms can include difficulty concentrating, reduced libido and high blood pressure.

Creatine Kinase

Creatine kinase is an enzyme found in various tissues in the body including the heart, brain and skeletal muscle. When we do intensive exercise muscles become damaged and increased amounts of creatine kinase are released into the blood. Elevated levels are consistent with muscle pain or weakness.

Muscle recovery can be aided by eating a nutritionally balanced diet and ensuring you get sufficient recovery periods between exercise. If you experience muscle damage due to exercise a break of at least one week should help to reduce creatine kinase levels. [5]

Creatinine and eGFR

Creatinine is a waste product which is produced from creatine, a compound which has a major role in the production of energy needed for muscle contraction. Creatinine is removed from the body by the kidneys and released in urine therefore levels of creatinine in blood is a good indication of how effectively the kidneys are working. It is used in a kidney function test called the estimated glomerular filtration rate (eGFR).

Individuals with high muscle mass will have higher levels which may be outside the normal range, and vice versa for individuals with low muscle mass. Creatinine and eGFR levels will rise immediately following strenuous exercise (or injury) but should then return to baseline following recovery.


C-reactive protein (CRP) measures the amount of inflammation in your body. CRP has been shown to increase immediately in response to exercise. However, this increase should return to normal within 20 hours of the exercise being carried out. Regular testing can establish a trend. [6]


Rest and recovery are often an afterthought when it comes to planning your training and racing. However signs of overtraining and underperforming emphasise the need for recovery. Regular testing with Edge can establish a pattern of how your body responds to intensive exercise or racing. This is why we offer a subscription for our tests, you can alter the reoccurrence date to suit your needs. 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. Allowing adequate recovery time, as well as the correct nutrition and getting enough sleep will enable your body to perform at its best.

You can learn how your body recovers and how long it needs between events in order to optimise your season. Get it right and reap the rewards!

  1. Statuta, S, M et al. (2017). Relative Energy Deficiency in Sport (RED-S). British Journal of Sports Medicine: 51(21) p 1509.

  2. Baudrand, R and Vaidya, A. (2015). Cortisol Dysregulation in Obesity-Related Metabolic Disorders. Current Opinion in Endocrinology, Diabetes and Obesity: 22(3), pp 143-149.

  3. Lovallo, W, R., Farag, N, H and Wilson, M, F. (2006). Cortisol Responses to Mental Stress, Exercise and Meals Following Caffeine Intake in Men and Women. Pharmacology, Biochemistry and Behaviour: 83(3), pp 441-447.

  4. Hill, E, E., Zack, E., Battaglini, C., Viru, M., Viru, A and Hackney, A, C. (2008). Exercise and Circulating Cortisol Levels: The Intensity Threshold Effect. J Endocrinol Invest: 31(7), pp 587-91.

  5. Kindermann, W. (2016). Creatine Kinase Levels After Exercise. Dtsch Arztebl Int: 113(9), pp 344

  6. Rauhe Mouridsen, M., Wendelboe Nielsen, O., Malchau Carlsen, C., Mattsson, N., Ruwald, M, H., Binici, Z and Sajadieh, A. (2014). High-Sensitivity C-Reactive Protein and Exercise-Induced Changes in Subjects Suspected of Coronary Heart Disease. Journal of Inflammation Research: 7, pp 45-55.