Blood Tests for Athletes to Boost Health and Performance
Blood Tests for Athletes to Boost Health and Performance
The new year is a prime opportunity for athletes to reflect on past performances, set new goals, and strategize on maximizing potential in the upcoming season. Effective strategies include hiring a coach, sport dietitian, and personal trainer, prioritizing sleep, and delving deeper into your physiological health and well-being. For many athletes, health evaluations can be akin to car maintenance – taking it to the shop when the check engine light comes on. If it’s been a while since your last evaluation, starting the year with one can identify necessary changes before the race season begins.
Blood testing is the most effective starting point for assessing health as it evaluates key biomarkers, nutritional status, potential deficiencies, and overall physiological health. This foundational information can inform athletes’ training, recovery, and nutritional strategies, ultimately laying the groundwork for a successful year ahead.
A standard blood panel consists of a complete blood count (CBC), a basic or comprehensive metabolic panel (BMP/CMP), and possibly a lipid panel. These tests evaluate red and white blood cells, electrolytes, blood glucose, and liver and kidney function. While these tests provide a valuable start, they hardly constitute a strategy for optimizing health and performance and can overlook important biomarkers. Most patients either don’t know what to request or are not athletes seeking to optimize their health and performance. It highlights the importance of taking charge of your health, which is easier than you may think.
In the past, athletes relied on medical professionals to order and interpret lab tests, but today, many options exist. Ultimately, knowing what biomarkers to request can empower athletes to take greater control of their health.
KEY BIOMARKERS
Athletes can explore a range of additional tests not included in a standard lab panel that provides deeper insight into their health, performance, and recovery. Below are some common tests to consider requesting, their significance to optimizing performance, and how to interpret the results.
FERRITIN
Aside from hemoglobin, hematocrit, and total iron included on the standard CBC panel, ferritin is a blood protein containing iron, which reflects your body’s available iron stores and is critical for carrying oxygen to working muscles during exercise. Ferritin levels below 30 ng/mL indicate iron deficiency. Higher than normal levels may indicate iron overload or inflammation.
Optimal Range: 65-150ng/mL
- Serum ferritin 20-40ng/mL, supplement with 27mg elemental iron in a daily multivitamin.
- Serum ferritin <20 ng/mL, supplement with 325mg ferrous sulfate once daily. Obtain a follow-up ferritin test after 100 tablets.
When supplementing with iron:
- Avoid calcium, soy-containing food, coffee, tea, red wine, and spinach for 2 hours before and after iron supplementation – as it inhibits iron absorption.
- To enhance iron absorption, take a vitamin C supplement (500mg) or consume Vit C-rich foods (citrus fruits and fortified fruit juices) simultaneously.
VITAMIN B12 plays a key role in producing red blood cells (RBC), oxygen transport, energy production, and muscle function and supports protein synthesis and cell repair. Vegans, vegetarians, and athletes over 50 are most at risk for B12 deficiency.
Optimal Range: 400-700 pg/mL
Supplementation may be necessary for athletes with a vitamin B12 concentration below 400pg/mL. Supplement with 500-1000 mcg daily or consult a healthcare professional on recommendations based on your specific health needs and conditions.
VITAMIN D is a hormone responsible for many bodily functions, including regulating calcium and magnesium. It is especially important for brain and bone health, the immune system, and possibly sleep and cognition. Many people have suboptimal vitamin D levels and require additional sunlight or supplementation.
Optimal Range: >50-80 ng/mL
- If below the optimal range, take 2000 IU Vit D3 daily and retest in three months.
- If above the optimal range, stop supplementation.
It’s important to have your vitamin D levels tested before supplementing to establish a baseline. In this case, more is not better.
THYROID FUNCTION TESTS
Proper thyroid function is vital for almost every system in your body, and poor thyroid function can negatively impact the health of an otherwise healthy person.
*If biomarkers are outside the reference range, consult a healthcare professional on recommendations based on your specific health needs and conditions.
- TSH: commonly ordered on anyone with a potential thyroid issue and is a good screening test for thyroid dysfunction. An abnormally low TSH means your thyroid produces too much hormone (hyperthyroid); an abnormally high TSH means your thyroid produces too little hormone (hypothyroid).
- Free T4 tests the amount of unbound T4 in the blood, which can give insight into thyroid function. It is recommended for thyroid dysfunction or abnormal TSH.
- Free T3 tests the amount of unbound T3 in the blood. It is the most active form of thyroid hormone, but its levels can be somewhat volatile, so it must be considered with TSH and Free T4.
| Lab | Reference range |
| TSH | 0.27-4.2 uIU/ml |
| Free T4 | 0.93-1.7 ng/dl |
| Free T3 | 2.0-4.4 pg/ml |
METABOLIC HEALTH-INSULIN RESISTANCE
These tests assess glucose disposal and insulin sensitivity. Hemoglobin A1c (HbA1c) and fasting glucose are standard tests covered by insurance and should be easy to obtain; fasting insulin and an oral glucose tolerance test (if implied) may not be covered by insurance.
*If biomarkers are outside the reference range, consult a healthcare professional on recommendations based on your specific health needs and conditions.
- Fasting glucose is the concentration in mg/dL of serum glucose after an 8-12 hour fast. If glucose is high, this usually indicates you are not disposing of glucose properly and may have insulin resistance. However, fasting glucose is not useful in detecting insulin resistance at an early stage.
- HbA1c: Hemoglobin is a protein found in red blood cells (RBC) responsible for carrying oxygen from the lungs to our organs. The average lifespan of a RBC is about 120 days, so HbA1c is a measure of average blood glucose over the past few months. An elevated HbA1c is a diagnostic criterion for prediabetes and diabetes or is used to assess glucose control in a pre-diabetic or diabetic. Like fasting glucose, HbA1c is not useful in detecting insulin resistance in its earlier forms.
- Fasting Insulin measures how much insulin is present in the blood after an 8-12 hour fast. High levels suggest insulin resistance, as more insulin is required to maintain normoglycemia. Typically, fasting or postprandial insulin levels rise years before fasting glucose and A1c rise; therefore, fasting insulin is a valuable proactive biomarker for identifying metabolic health in the early stages.
- Oral Glucose Tolerance Test (OGTT) is likely the best test for getting a clear picture of glucose disposal and insulin sensitivity. It involves drinking 75 g of glucose and checking blood glucose and insulin levels at 30, 60, and 90 minutes to evaluate how your body responds to a glucose challenge. Interpreting the results requires some nuance, but in general, if your body is unable to dispose of the glucose well (i.e., blood glucose stays elevated) or you need large amounts of insulin to dispose of the glucose (i.e., insulin is very elevated and stays elevated), these are indicators of metabolic dysfunction. This test is indicated if fasting insulin, glucose, or HbA1c are elevated.
| Lab | Reference range |
| Fasting Glucose |
|
| Hgb A1c |
|
| Fasting insulin |
|
| OGTT | Interpretation is complicated, but insulin should peak at 30 minutes and then decrease, and blood glucose should not exceed 140 mg/dL at 30 min. |
For OGTT interpretation
| Glucose | Insulin | |
| 0 min | < 90 mg/dL | < 6 uU/mL |
| 30 min | < 140 | < 40 |
| 60 min | < 120 | < 30 |
| 90 min | < 100 | < 20 |
HIGH SENSITIVITY C-REACTIVE PROTEIN (hs-CRP) C-reactive Protein (CRP) is an acute-phase protein synthesized by the liver that increases in the blood with inflammation. A standard CRP test measures high levels of protein associated with significant inflammatory states (>8 mg/L). However, the highly sensitive CRP (hs-CRP) blood test is more sensitive than the standard CRP assay at detecting smaller increases in CRP associated with cardiometabolic disease (1.0-3.0 mg/L).
| Lab | Reference range |
| hs-CRP | Optimal: < 1 mg/L Low-grade chronic cardiometabolic inflammation: 1-3 mg/L High: > 3 mg/L |
CARDIOVASCULAR HEALTH
A standard lipid panel includes specific cholesterol content by measuring the mass (in mg) of all the cholesterol molecules carried within a fixed volume of blood (in dL), including LDL-C, HDL-C, Triglycerides, Non-HDL-C, VLDL-C, Trig/HDL-C Ratio, and Total Cholesterol.
However, lipoprotein testing, which is not included on a standard lipid panel, reports the concentration of lipoprotein concentrations, not their lipid content.
*If biomarkers are outside the reference range, consult a healthcare professional on recommendations based on your specific health needs and conditions.
- Apolipoprotein B (apoB) is the concentration of all circulating apoB-carrying particles (LDLs, VLDLs, IDLs). Due to longer serum residence times of LDLs, >90% of an apoB level represents LDL particles. ApoB is causal for atherosclerotic cardiovascular disease (ASCVD). For this reason, it is the most important lipoprotein metric used to estimate ASCVD risk and serves as the major target of therapy. Results range from the 5th percentile with an ApoB of 62mg/dl to the 95th percentile with an ApoB of 140mg/dl.
- Lipoprotein(a) “little a” is a lipoprotein particle consisting of an LDL with an additional attachment, a protein called apoprotein(a), which renders the entire particle increasingly atherogenic and potentially damaging to the aortic valve in the heart. The quantity of Lp(a) produced by the liver is variable, dependent on your genetics, and does not naturally change over time. Currently, no FDA-approved therapy for targeting and lowering Lp(a) exists. However, PCSK-9 inhibitors, potent drugs for lowering LDL-C/apoB, can also reduce Lp(a) by 25%, which may have additional protective benefits.
| Lab | Reference range |
| ApoB |
|
| Lp(a) |
|
BODY COMPOSITION ANALYSIS
A DEXA (dual-energy X-ray absorptiometry) scan is considered the gold standard for measuring bone density and assessing muscle mass and body fat, including subcutaneous and visceral fat. It is commonly used to diagnose conditions like osteopenia and osteoporosis and to evaluate the risk of fractures.
*If results indicate any concerns, seek medical advice from a healthcare professional for personalized recommendations based on your specific health needs and conditions.
Interpreting the Results
It’s important to note that lab results come with reference ranges that indicate values considered “normal” but not necessarily optimal. Typically, a reference range reflects the percentile within a given population, where around 80-95% of individuals fall within that range. These ranges are expressed as a single value (e.g., <40 U/L) or as a range (e.g., 300-1000 ng/L). Since test results can vary significantly among different laboratories due to different assays, it’s crucial to interpret results against the reference ranges provided by the specific lab that conducted the tests. However, population norms do not necessarily represent what is ideal for optimal health and performance. Therefore, alongside evaluating test results against standard reference ranges, we should also consider them with the goal of optimization.
Prioritizing health evaluations and understanding key biomarkers is essential for reaching peak performance. Athletes can fine-tune their training regimens, enhance recovery strategies, make informed nutritional choices, and mitigate potential health issues by taking proactive steps to assess and optimize physiological health. A well-informed athlete is a powerful athlete, ready to take on any challenge that lies ahead.
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