Support your fitness

Do you want to push your fitness to the next level? A personalised blood test can measure things that affect your performance — like your vitamin D and iron levels, thyroid, and more.

How can a fitness blood test help you?

This test was created by our in-house GPs to measure things that play a role in your performance and recovery. With your blood test results and detailed GP report, you'll get advice to improve your fitness performance — like sleep, diet, and other lifestyle factors.


Vitamin D

Vitamin D helps your body absorb calcium and helps with maintaining healthy skin and bones. It also plays an important role in your immune system. Vitamin D deficiency is linked to fatigue, bone and muscle pain, as well as getting ill more often than usual.



Your body uses iron to make haemoglobin — a part of red blood cells that carry oxygen around your body. If you don't get enough iron you might develop iron deficiency anaemia, which can affect your fitness performance. Tiredness, shortness of breath, and heart palpitations are signs you might be deficient.


Folate (vitamin B9)

Folate plays an essential role in producing red blood cells — these carry oxygen around your body. If your folate levels are low, you might feel tired and less motivated. You might also experience pins and needles, heart palpitations, shortness of breath, and muscle weakness.


Vitamin B12

Vitamin B12 is essential for a healthy brain and nervous system. It also works closely with folate to make red blood cells — these carry oxygen around your body. If you don't get enough vitamin B12, it can affect your endurance and performance.



Testosterone is a hormone that's essential for women. It's important for muscle mass and strength, bone health, and red blood cell production (these transport oxygen around your body).


Liver profile

Your liver plays a key role in digesting and metabolising food. This process helps provide energy for your body to use. If your liver isn't working correctly, it can affect this process and your fitness levels. Poor liver health can also cause low energy levels. Find out more about testing your liver health.


Thyroid function

When your thyroid gland isn't functioning properly, it can affect your exercise tolerance and performance. Conditions like over- or underactive thyroid might cause stiff and weak muscles, and can affect your heart function.

What else do you get?

Not only will you get GP-reviewed results. You will also get evidence-based recommendations to improve your health and understand how to perform at your best.

Your journey to better fitness

Illustration of a Thriva blood test kit

Do your test at home

Your kit arrives in 1-2 days. Find out how to collect your sample at home. You’ll need to fill 2 tubes for this test — around 10 drops of blood.

Illustration of results and GP report

Get results in 48 hours

Free post your sample to our lab and get your results in 48 hours. Access your GP-reviewed report in your results dashboard.

A Thrivaling seeing tips on how to improve their health

Improve your health

Our doctors give you evidence-based tips to help you improve your endurance. And you can access articles, podcasts, and recipes.

Related articles

Podcast on how running affects your health
Article about the benefits of omega-3 fatty acids
Article about vitamin D

Want to know more?


How does your subscription work?

Your blood test arrives every 3 months. You can change your subscription and how often you’d like a test on your account dashboard. We’ll remind you that payment is due 3 days before your kit arrives. And you can pause, change, or cancel at any time.


Data protection

Your data is in safe hands. We use the latest encryption technologies and take our Data Protection obligations seriously.


Will a GP write your report?

Our doctors review your blood test results and upload a detailed report to your account dashboard. They also give you advice to help support your fitness or manage an existing condition.


How to collect your sample at home

Learn how to collect your finger-prick blood sample at home by following our instructions. You can access these on the app too. It takes around 30 minutes to complete the process at home.


How long does it take to get your results?

Understanding your health should be quick and easy. That’s why our doctors share your results within 48 hours. And you can access your data at any time.


How do you know when your results are ready?

We’ll email or text you to let you know your blood samples have been received, processed, and are ready to view on your results dashboard.


Your sample will be analysed by a CQC-registered and UKAS accredited lab. This finger-prick test and kit are CE-marked.

Laura's plan

Running woman with trees

Laura wants to make sure she’s getting enough of the nutrients that help her recover from marathon training.

Vitamin B12 to support energy
Vitamin B12
for muscle recovery
Iron to support endurance

Get to know your body better

Whether you're training for your next marathon or want to improve your lifestyle habits, take the first step with a home blood test.


Data protection

Your data is in safe hands. We use the latest encryption technologies and take our Data Protection obligations seriously.

See privacy policy
Illustration graph


Our blood testing kits are CE-marked, and we work with UKAS accredited labs who are registered with the CQC.

See labs and accuracy