As a lot of you know, I'm always signed up to one course or another to better understand my clients' functional test results. I firmly believe that knowledge is the most powerful tool I have — not just for my own clients but for anyone who wants to take a proactive approach to their health rather than waiting for something to go wrong. This blog shares a handful of the most useful insights I picked up recently, particularly for those of you who train hard, supplement regularly, or simply want to know how to get the most accurate picture from your blood work.
Cracking the Code: Blood Tests for Athletes
First up, let's talk creatine. If you're hitting the weights hard and building muscle, your creatine levels might look sky-high. But here's a pro tip: Don't panic! This is totally normal for resistance training warriors. The real magic? Ask for a cystatin C test alongside your standard blood work. This will give you a much more accurate picture of your kidney function, independent of your muscle mass.
The Perfect Blood Test: Timing is Everything
Want the most accurate blood work? Here are my top tips:
- Hydration is Key: Drink at least two litres of water before your test
- Rest Up: Avoid heavy training for 48 hours pre-test
- Timing Matters: Get tested between 8 AM and 11 AM
- Ladies' Note: Aim for mid-cycle and keep consistent on retests — same time of the month to accurately monitor changes
- Gentlemen: Avoid prolonged seated activities 48 hours before to get more accurate prostate readings
Supplement and Performance Insights
For my bodybuilding friends, here's a crucial tip: Get your blood tests done at the peak of your supplement cycle. This gives you the most accurate snapshot of how your liver is handling your performance regime. Don't wait until things have settled down — you want to know exactly what's happening in your liver when you're pushing your limits!
Surprising Blood Test Quirks
Here's a nerdy gem I picked up: Runners and martial artists, listen up! There's something called 'heel strike haemolysis' that can actually affect your iron levels. The repeated impact can shorten your red blood cell life — who knew?
Want help making sense of your blood results? Book a one-to-one consultation tailored to your health history.
Book Consultation →Pro Tip Alert: If you have low iron, folate, or B12, check your bilirubin levels. It can reveal if your red blood cells are dying faster than they should. The knock-on effect can make your HbA1c (blood sugar) reading look better than it really is. Your HbA1c is the average blood sugar level over a period of 3 months. If your red blood cells are dying early (they should live for 3 months), your HbA1c may look better than it actually is!
Why 'Normal' Isn't Always Optimal
Something that comes up again and again in functional testing is how wide and forgiving the 'normal' ranges are on standard NHS blood tests. They're designed to catch disease, not to optimise health. A result that sits within range doesn't necessarily mean that result is ideal for you — it just means you're unlikely to be in acute danger. Functional reference ranges are typically much tighter, and they give a completely different picture of where someone sits on the spectrum of health. The same blood test, interpreted through a functional lens, can reveal so much more than the same result filed away as 'normal' by a GP.
Functional testing has been one of the most important tools in my practice. When I can look at a client's blood results alongside their symptoms, history and lifestyle, patterns emerge that simply wouldn't be visible from a standard check-up. Low ferritin showing up alongside poor sleep and hair loss. Borderline thyroid markers that explain years of fatigue and cold hands. Vitamin D sitting in the 'normal' range but well below the optimal level for immune and mood support. The information was always there — it just needed the right lens to interpret it.
The bottom line? Knowledge is power, especially when it comes to your body. These little insights can help you train smarter, not just harder.
Stay curious, stay healthy, and keep pushing those boundaries!
If you need help acting on your blood results, please book in a call with me and we can combine them with your present symptoms, past medical history, lifestyle and nutrition to reach your goals moving forwards.
Lots of Love
Niki x
