Anna Boniface - Why I test my bloods during training


We spoke to endurance athlete and physiotherapist Anna Boniface about the benefits of blood testing with Medichecks in sports training.


Emily Condon
BSc (Hons) Biological Sciences

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Anna Boniface was the first non-elite woman to cross the finish line at the London Marathon in 2017. She is currently recovering from Relative Energy Deficiency in Sport (RED-S) and is gradually returning to full training. Thanks to a Medichecks blood test, Anna is able to monitor her recovery. Tracking her baseline biomarkers has helped guide her medical management, training and nutrition to ensure she is as robust as possible before transitioning back into competition.

We chatted with Anna about how blood testing is important in sports training. 

1. Why is it important for endurance athletes to have regular health checks?

For endurance athletes, there's a fine line of training hard enough to get fitter and faster whilst maintaining health. Once that line is crossed illness and injury are likely to follow. It’s difficult for an athlete to know exactly when they have crossed that line until it’s too late.

Pre-season health checks are essential for athletes to maximise their health before tough training blocks. Baseline markers can be monitored throughout training cycles and necessary adaptations to training, recovery and nutrition can quickly be put in place to keep the athlete on track to perform.

2. Has your health check given you a valuable insight into your inner health?

I’m currently getting back to full training following a stress fracture as a consequence of Relative Energy Deficiency in Sport (RED-S). My latest health check has shown that I am healthy which is reassuring. Most importantly, it provides key markers of recovery from RED-S, for example, female sex hormones, bone profile, leptin and IGF-1. These have been monitored closely by my doctors over the last few months. It helps piece the puzzle together to guide my medical management, training and nutrition.

3.  Was there anything unexpected about your results? If so, will you be changing anything to try and change/improve this?

I was quite surprised by my liver function which showed raised liver enzymes. This is common after strenuous exercise, however, I didn’t perceive my training to be particularly taxing at the time. It’s highlighted that my training is causing more stress than I perceived. My body is clearly working harder than normal to recover after sessions. This has given me the vital information that I need to make the necessary changes after training sessions to ensure I recover better.

4. Why, when training, is hormonal health so important?

As athletes, we train hard to get physiological adaptations. These adaptations are driven by hormones which are stimulated during sleep and recovery. Hormones are responsible for bone health, protein synthesis, tissue repair and muscle growth. When training too much and not eating enough an athlete will be in an energy deficit. This will cause hormones to seesaw. For female athletes, a key sign is amenorrhoea (cessation of periods). Over time, these low hormone levels have a profound effect on health and performance. One of the most significant is declining bone health and stress fractures.
Until my stress fracture, my lack of periods was never a concern to me. I now understand how essential it is for female athletes and the huge impact hormones have. I have been taking hormone replacement therapy to help protect my bones. This is most importantly combined with correcting the energy deficit through working with a dietician and correcting training errors. My latest bloods have shown my hormones remain low but despite this, I had a breakthrough last month with my first period in years! I would urge any females without periods to get their hormones checked. They are incredibly important.

Anna has her blood tested regularly with Medichecks and has a clearer insight into the actions she needs to make to optimise her health, performance, and recovery from RED-S. If you are training for an event or working towards a fitness goal, Medichecks range of Endurance and Sports Checks allow you to gain great insights into your inner health to allow you to perform at your best. Our Endurance Fit is designed to check all the markers which can impact training and race performance. 

Medichecks Sports Checks

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