Athletic training programs force physiological adaptations, which means it is not uncommon to see abnormal results in athletes. Athletes push themselves to become bigger, faster, and stronger – a process which breaks the body down and can cause biochemical chaos. I recently had a blood test done at our lab with some unexpected results...
Above, are the abnormals of the resulting blood test. The most clinically worrisome of these is the highly elevated Creatine Kinase, or CK. CK is an enzyme that catalyzes the conversion of creatine into phosphocreatine (PCr) via the transfer of a phosphate from an adenosine triphosphate (ATP) molecule. This produces adenosine diphosphate (ADP) as a result. This process is integral to energy production, transfer, and storage in the body. In cells that consume ATP rapidly – especially skeletal muscle – we tend to see high concentrations of CK.
The heart is also a hub for CK, and this is where the concern for high serum CK levels primarily lies. High levels of CK have shown to be indicative of heart attacks and associated myocardial damage. So, it is a shock to the old ticker to see serum CK out of range by 113 U/L. However, high serum CK isn’t exclusive to cardiac muscle damage. Skeletal muscle damage, like that caused by athletic training programs, can also elevate serum CK.
Accordingly, I recalled a particularly rough training session two days before my blood test. The session consisted of:
10 x 400m @ 70 secs per 400m
10 x 3 squats @ 70% of 3rm EMOM
10 x 3 strict press @ 70% of 3rm EMOM
4 x maximal pull ups
4 x maximal dips
Whether you're familiar with this workout routine or not, know that it’s pretty high intensity. This session had really beaten up my skeletal muscle, causing a massive release of CK into my blood, peaking about 48 hours after the workout. This explained my elevated CK in a more reasonable (and comforting) context to the clinically indicated heart attack.
Vitamin B12 was easy to explain. In order to get all the vitamins and nutrients my body needs to train at the level I want, I take 3 multivitamin pills everyday spread throughout with meals. I have done this for about 5 years very consistently. Taking my blood test at 2 pills in for the day meant that all my micronutrient profiles were spiked, with B12 out of range. Most athletes should have a surplus of many key performance associated vitamins - such as iron and Vitamin D - which indicates they have their nutrition dialed in.
Cortisol, the stress hormone, is another marker typically elevated in athletes, and can help predict overtraining due to its relationship with muscle breakdown and stress. Given the muscle damage indicated by the CK level, it was natural that my cortisol would be elevated too. However, cortisol can have a negative impact on testosterone, which is key to recovering from hard training sessions. Therefore, it is important to monitor cortisol closely to tailor your training routine to your biochemistry.
Remember, the body has a hard time differentiating life stress from workout stress. Both cortisol and general CNS fatigue can be increased from all types of stresses, so taking an extra day off training every couple weeks can be very beneficial. I always program a lighter de-load week for every 4-5 weeks of hard training.
The Bottom Line
In other athletes, it is common to see low white blood cell counts, while hematocrit and platelet counts may be elevated due to hydration status. Also due to hydration, electrolyte balance (specifically Na+ & K+) may be outside the normal range. The lifestyle of an athlete at many levels is abnormal, and so too are their blood tests. Always keep your doctor informed regarding your training schedule, and consult them regularly.