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If you order your test before midday on a Monday to Friday then your kit will be dispatched the same day. All our kits are sent out via Royal Mail first class post, so it should be with you within 1-2 working days.

When will I get my results?

We aim to deliver your results within 2 working days of your blood sample arriving at our lab.

How do I view my results?

When you buy your test, we will ask you to create an account with us during checkout. This will give you access to your own, secure health dashboard where you can view your results.

How secure is my data?

We have strict processes in place to ensure the protection of your data. Following GDPR the company also operates under tight legal rules about the sharing of data which ensures that data is only shared if it is crucial to the delivery of our service. For example, our doctors see customer results at the time of review, however, after review, access to results is withdrawn.

How do I find out my results are ready?

We keep you updated throughout the process by email and text message. We will let you know when your blood sample has arrived at our lab. Once the blood sample has been analysed one of our doctors will review your results. Once your results are ready, we will email you and send you a text message to let you know your results are ready for you to view in your health dashboard.

Does a doctor review my results?

We have a team of doctors and nurses who look at all results and will comment on any results that are outside of the normal range for your age.

What is Triiodothyronine (T3) & Why Is it Important for Athletes?

1 min read

Published on

May 22, 2025

Written by

EDGE

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What Is Free T3?

Free T3 is the active form of thyroid hormone, directly responsible for regulating metabolism, energy use, and thermogenesis. It’s converted from T4 and is the most metabolically powerful thyroid hormone.

Athletes with disrupted T3 levels may struggle with recovery, fatigue, and poor adaptation to training.

"Free T3 is the active form of thyroid hormone and a sensitive marker of metabolic slowdown, often affected by under-fuelling or stress. I recommend testing T3 in conjunction with TSH and free T4, especially if you're noticing fatigue, poor recovery, or unexplained weight changes. Monitoring thyroid function every 6–12 months can help optimise training outcomes."

Dr Thom Phillips

What are normal Triiodothyronine (T3) levels for athletes?

We looked at blood test data from EDGE customers and found the median triiodothyronine levels for women are 4.4 pmol/L and 4.9 pmol/L for men.

Here is a breakdown of Triiodothyronine (T3) levels by age:

Table 1: T3 Levels in Men and Women by Age Group (pmol/L)
Age Group	Female	Male
18-29	4.6	5.4
30-39	4.4	5
40-49	4.3	4.8
50-59	4.1	4.8
60+	3.9	4.6

Source: EDGE customer blood test results Apr 2023 – March 2025.

The labs we used to analyse blood samples state a healthy range for Triiodothyronine (T3) is generally between 3.1-6.8 pmol/L.

Median T3 levels for male and female athletes in the UK, 2025.

How T3 Impacts Athletes

Energy & Fatigue

Low T3 can leave you feeling tired and cold, even with adequate rest. It can also impair muscle glycogen storage and slow down metabolic efficiency.
Training & Recovery

T3 influences protein synthesis and mitochondrial function. Suppressed levels can delay repair and slow aerobic adaptation.
RED-S Indicator

Low T3 is a classic sign of relative energy deficiency in sport (RED-S) and often appears in athletes who are under-fuelling or overtraining.