Blood Analysis and Recommendations for Active Individuals: Taking Performance and Recovery to the Next Level


Blood analysis provides a unique understanding of an athlete’s health and performance. Certain biomarkers like vitamin D and ferritin can directly impact athletic performance while others, like cortisol and creatine kinase, can provide insight into overtraining and injury prevention. Athletes can now use blood testing to pinpoint areas to improve and implement effective changes to improve performance. Find out how athletes of all levels use blood biomarker analysis through InsideTracker's personalized performance and nutrition system to optimize health and athletic performance and how all athletes can benefit.

How an Ultramarathoner Uses Blood Tests to Prevent Fatigue

Ultramarathoner Crystal Seaver isn’t new to running 50- and 100-mile races in her spare time. But after one 100-miler, she found herself struggling to bounce back both physically and mentally. Before beginning another training cycle, she analyzed her bloodwork with InsideTracker to learn more about her body. The insights from her test showed Seaver that she needed to address her iron and ferritin levels.

Iron deficiency is one of the most common nutritional deficiencies around the world, especially in women. Athletes face a greater risk of low or deficient iron status because iron is lost during heavy training periods through sweating, running and the gastrointestinal bleeding that can sometimes follow intense workouts.

How do low iron levels impact athletic performance? First, let’s start with some basics on iron. Iron is part of the protein hemoglobin—a component in all red blood cells. RBCs are responsible for transporting oxygen to cells, tissues and organs throughout the body. Therefore, iron deficiency tends to lead to lower levels of both red blood cells and hemoglobin. This results in blood carrying less oxygen to muscles and the brain, which can negatively impact performance. Symptoms of iron deficiency can also include frequent injury, a weakened immune system, chronic fatigue, irritability and a high exercise heart rate.

Ferritin, a protein that stores iron, is the best indicator of iron in the body, yet physicians do not routinely check this marker. Athletes, especially female athletes, should track ferritin status to avoid fatigue and plateauing during athletic events. InsideTracker provides ferritin, serum iron, hemoglobin and RBC tests, as well as specific recommendations on how to improve them.

How Blood Tests Became Part of an Olympian’s Training Routine

U.S. Olympic track cyclist Sarah Hammer spent hours training and building her endurance. But for her to reach her athletic potential she needed to take a closer look at what was going on inside. An InsideTracker blood analysis revealed that her vitamin D levels were very low. Vitamin D deficiency is one of the most common nutrient deficiencies across the globe, even among athletes. A 2016 study found that 32% of professional basketball players were deficient in vitamin D, while 47% had low levels of the nutrient.

Vitamin D plays many essential roles in the body, especially when it comes to athletic performance. Vitamin D increases muscle mass and strength, improves bone health (along with calcium), increases the size and number of the muscle fibers used for short bursts of speed and power and improves lower body strength. Adequate Vitamin D levels can also reduce inflammation in the body, specifically the inflammatory marker CRP. This meta-analysis from the journal “Nutrients” found that vitamin D supplementation can lower serum CRP levels by 20%. According to this randomized control trial, low vitamin D levels can also lead to decreased testosterone, especially in men. Testosterone is an anabolic hormone produced in both men and women that helps increase bone strength and stimulates muscle mass and strength.

Using the evidence-based interventions and knowledge gained through blood testing with InsideTracker, Hammer increased her vitamin D levels and went on to win two Olympic silver medals in track cycling.

Using Blood Markers to Prevent Overtraining

Blood testing with InsideTracker can help athletes uncover potential overtraining syndrome. Kris Brown, an endurance athlete and ultramarathoner, uses InsideTracker to help prevent overtraining after his results showed the early signs of OTS, including elevated cortisol.Cortisol, also known as the stress hormone, is a steroid hormone produced by the adrenal glands. It responds to both physical and emotional stress and plays a crucial role in many essential physiological functions. Overtraining may lead to physical stress and high cortisol levels. If athletes experience a constantly high-cortisol state, they face a greater risk of chronic fatigue, high blood glucose levels and even weight gain. As a response to his blood test results, Brown implemented the science-driven recommendations provided by InsideTracker.

After completing her second Boston Marathon, Danielle Bohn was searching for ways to enhance her recovery and performance. By following her personalized InsideTracker recommendations, sticking to a proper training plan and implementing recovery protocols, she ran her fastest marathon and felt incredible doing it. Bohn also found herself recovering faster between workouts and was able to push her body farther than she ever had before. When certain biomarkers such as cortisol and creatine kinase are elevated, runners find themselves unable to recover properly and their performance suffers.

Creatine kinase is an enzyme that rises when muscle damage occurs. Test results of this biomarker allow athletes to see how their bodies react to training load and intensity. CK peaks about two to four days after intense exercise and returns to normal levels (< 200 units) over the course of a few days, depending on the intensity of the exercise. This study showed that the CK levels of marathon runners are elevated after endurance training and competition and took about seven to 14 days post-marathon to return back to baseline.

There is also a correlation between CK level and injury. A chronically elevated CK will most likely result in muscle pain, weakness, injury and more—not ideal for top athletic performance. InsideTracker considers age, gender, ethnicity, type of athletic activity (swimmers should have a lower level of CK than soccer players, for example) and determines your personalized range of CK. If this level is too high, InsideTracker will provide several personalized options for reducing your levels, including dietary changes, exercises and supplements.

Why Should Athletes Use InsideTracker?

Blood testing is a safe, clean and effective way for athletes to achieve a competitive edge in a fair way. “Athletes are willing to inject their bodies with drugs to get an advantage, so why not withdraw information to improve performance naturally?” the founder of InsideTracker, Gil Blander, says. Blander emphasizes that to optimize your body’s physical capabilities, it’s necessary to have scientific evidence about your unique blood biochemistry. The InsideTracker team spent over 12 years analyzing 37,000 peer-reviewed research papers to find the most critical biomarkers to improve human performance and identify the nutrition, supplements, lifestyle and exercise interventions to optimize them.

What makes InsideTracker unique is its identification of an “optimal zone” in the blood analysis. This number is specific to each individual and considers each unique demographic information, including age, gender, ethnicity, activity level and lifestyle and performance goals.

InsideTracker’s sophisticated algorithm determines the optimal zones for each marker based on the latest peer-reviewed research. For example, the normal generic range for a woman’s ferritin level is between 12 to 150 ng/dL. But InsideTracker recommends that an active woman in her 20s should have blood levels of ferritin between 40 to 150 ng/dL for optimum performance. If you're not in this zone, the algorithm recommends effective and simple interventions involving diet, supplements and training modifications that are specific to your needs. The InsideTracker team created the algorithm to produce the most accurate recommendations for its users based on cutting-edge scientific research extracted from peer-reviewed scientific literature.

From amateurs to elites, InsideTracker has helped thousands of athletes improve their performance and crush their PRs while promoting longevity and durability in sport. By combining the latest scientific research with information about your body’s unique biochemistry, InsideTracker can help you continue to run and train for the long haul.

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