Female Doctor Preparing Patient For Blood Draw In Clinic

Post and Pre-Season Blood Tests for Athletes

BY Nick Busca

Taking a post season (or pre-season) blood test may help shape your training and nutrition—and give you valuable information about your health.

In a season that never (really) was, talking about an off-season might sound like quite an oxymoron. Still, a handful of lucky few were able to race this year—and even if you weren’t, it’s good practice to follow a typical calendar year so that you don’t lose touch with the natural rhythm of seasons.

One good habit is undoubtedly getting a blood test done at the end of a big training cycle, and/or before you start a new one.

I was among those who raced a full Ironman this year (Estonia, in September). As I do every year in this period, before the new routine, I did a comprehensive blood test. I wanted to see where my physiological parameters were after a solid year of training (12 to 16 hours per week despite lockdown) and to catch up on potential deficiencies coming from that.

However even if I hadn’t raced, I’d still want to get a full picture of my health before embarking on a new season. Whether you’re coming off a period of heavy training or full quarantine lockdown, a blood test can give you valuable information as you set up your next year. 

Type of Tests

Luckily, these days you don’t need to go to a lab or to a doctor to get a blood test. Several companies have now set up at-home testing through a simple finger prick. Purchase the kit online and you get a box delivered at home with all the essentials you’ll need. You then perform the test early in the morning, seal everything, and send it back. You usually get the results in 1-2 days either via email or through an app and an online profile.

Of course, if you prefer to get your blood taken by professionals, that may still be the most accurate and quick way to a result. I have to admit that depending on the provider’s guidelines and some blood clotting issues, it took me three times to have full test results from at-home kits. But that’s not the norm; I may have particularly thick blood (and was probably dehydrated too, particularly early in the morning), and once I changed the finger I was pricking, I was able to solve the issue.

Over the years, I have tried almost all the providers in the UK that advertise at-home kits to endurance athletes: Forth EdgeThriva, and Medichecks. There are other alternatives in the US, including Everlywell.

Which values should you look at?

Getting your results is one thing. Understanding them is another.

One value to look at is hormones. “These drive adaptations to exercise training, but also haematinics [the nutrients required to produce red blood cells], and vitamin D, particularly in the winter,” says Nicky Keay, an endocrinologist specializing in dance and endurance sports (as well as chief medical officer for Forth Edge in the UK.) 

She says that athletes should get blood tests done “to check in on if their endurance training, nutrition, and recovery are supporting positive adaptive changes, or not!” She adds that blood tests tell us “how our bodies are responding to external factors of training load, nutrition, and recovery.”

Keats suggests testing three to four times during the season and at critical points like “pre-season, end of the winter training block, in the pre-race season, and the end of a race season.”

In her experience, most of the issues endurance athletes face are due to “low energy availability and potential adverse consequences of relative energy deficiency in sports (REDs)”, she says. She has also written about these issues for Training Peaks, and she says a blood test can pinpoint deficiencies in advance to limit the negative consequences in the long term and support the demands of training and racing.


For about $120, here are the parameters I have had checked. Although the blood test providers will indicate how your test compares to their average levels, I highly recommend running your results by a professional as well. For example, one of my hormone levels was slightly high, but I consulted a professional who told me that since my other significant parameters were average, that single high digit was not a concern. 

Do not fall into the trap of seeing a red light and thinking everything is terrible! Speak to a professional specialized in endurance sports (most of these providers offer this kind of support too).

  • Hematocrit: volume percentage of red blood cells in the blood
  • Hemoglobin: the red protein responsible for transporting oxygen in the blood
  • Red blood cells: necessary oxygen transporters. They take it from the lungs to the cells around the body.
  • White blood cells: the number of white blood cells per volume of blood. White blood cells make up your immune system and help to protect the body against illness and disease.
  • Mean cell hemoglobin: the amount of hemoglobin inside the red blood cells.
  • Mean corpuscular hemoglobin concentration: concentration of hemoglobin inside the red blood cells.
  • Mean corpuscular volume: the average size of your red blood cells.
  • Mean platelet volume: the average size of blood platelets (corpuscules who play an essential role in clotting.)
  • Red blood cells distribution width: measurement of the variation of the size of your red blood cells.
  • Cortisol: steroid hormone that is released when the body is under stress. Anxiety, a restricted diet, or over-training can all cause cortisol levels to rise.
  • Follicle-stimulating hormone: regulates the functions of the reproductive system.
  • Luteinizing hormone: plays a vital role in the human reproductive system.
  • Prolactin: a hormone produced by the pituitary gland. Slight increases can occur as part of a stress reaction.
  • Testosterone: a hormone that affects the brain, bone and muscle mass, fat distribution, the vascular system, energy levels, sexual functioning, and fertility. 
  • Thyroid stimulated hormone: plays a vital role in regulating the production of hormones by the thyroid gland.
  • Thyroxine (T4): a test used to check that the thyroid is performing correctly. 
  • A Triiodothyronine (T3): test can indicate if the thyroid is performing correctly.
  • Vitamin B12: like folate, it has a vital role in the production of healthy red blood cells and has a function in nerve health. 
  • Ferritin: the amount of ferritin in the blood reflects the total level of iron stored within your body.
  • Vitamin D: plays an essential role in health, including in the development and preservation of healthy bones, boosting our immune system, muscle function, energy levels, and helping to reduce inflammation.
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About Nick Busca

Nicola (Nick) Busca is an Italian triathlon coach based in London. He is a Level 3 High-Performance triathlon coach with British Triathlon and also a Training Peaks Level 2 and an IRONMAN-certified coach. Before setting up his own club in 2018, Core – Ski and Triathlon Academy, he led swimming, cycling and running sessions with the London-based triathlon club Ful-on Tri and coached the swimming squads of Swim For Tri (also based in London). After more than 20 years racing and coaching alpine skiing, he needed a new challenge and started to train and compete in triathlons in 2012. He began with the Turin-based triathlon team Aquatica and received private coaching from former Olympian athlete Vladimir Polikarpenko, who raced in three Olympic games for Ukraine. In 2016 and 2017, he qualified for Team GB for both the ETU European Championships (middle distance) and the ITU World Championships (long-distance). He still races and tries to improve season after season.

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