Check-Up for Athletes

A defining characteristic of an athlete is the desire to improve performance through physical strength, endurance, mental work or other means and to gain an advantage in competition. By having blood tests using a functional medicine approach, athletes can better understand health- and performance-related biomarkers and can get the upper hand in their sport by optimizing their training and recovery plans.

Blood tests can provide information about health issues that affect performance, such as iron levels and nutritional status. Examining markers such as cortisol and other hormones can also help assess recovery efficiency. This article will discuss blood testing for athletes and how to use blood test results to improve performance.

Why Should Athletes Focus on Blood Testing?

Blood testing can be a valuable component of an athlete's training program and can be used to support optimal performance, recovery and overall health. While some biomarkers can directly affect athletic performance, others can be used to better understand an athlete's training program and recovery needs, and can help prevent injury and illness. By assessing internal stress levels, muscle health and possible deficiencies in the body, athletes and their coaches can better manage their training, recovery and nutrition and optimize their athletic performance.

Athletes can personalize their blood tests, taking into account any possible deficiencies in their diet (for example, a low-carbohydrate or plant-based diet), their health history and their athletic training goals.

The timing of laboratory tests also emerges as an important consideration. Some factors athletes should take into account when testing include: the time of day (which can affect hormones such as cortisol), hydration status (dehydration can affect laboratory results), the training load before the blood draw (certain markers rise in the post-training period) and, for female athletes, the menstrual cycle.

What Are the Best Blood Tests for Athletes?

There are several important blood tests that athletes should consider:

Vitamin D

Vitamin D helps prevent inflammation while supporting immune health and recovery. It has also been linked to increases in muscle strength, size and power. Low vitamin D levels have been associated with low testosterone levels, an increased risk of injury and stress fractures in athletes, and suboptimal muscle function.

Cortisol

Cortisol is a hormone produced in response to any type of stressor (physical or mental). It affects circadian rhythm, sleep patterns, blood sugar, blood pressure and energy levels. Persistently high cortisol levels can occur with a high level of training stress without adequate recovery, and increase an athlete's risk of fatigue, problems with weight control, inability to maintain muscle mass, sleep disturbances and injury.

Micronutrient Panel

Vitamins and minerals are essential for athletic performance and recovery, because these micronutrients are necessary for basic metabolic functions and hormone production and help muscles recover. Zinc, magnesium, iron and B vitamins in particular are important for athletes. Understanding these micronutrient levels can help fine-tune training and recovery needs and guide supplement use during periods of intense training.

Thyroid Panel: TSH, Free T4 and Free T3

Thyroid testing is important for athletes to optimize their performance, because low thyroid function has been associated with reduced exercise capacity and endurance performance. The thyroid is also sensitive to prolonged stress and overtraining, and suboptimal thyroid hormone ranges may indicate a need for better recovery methods. TSH alone cannot reliably detect ongoing changes, especially persistent stress combined with periods of heavy training. Therefore, a full panel that includes free T4 and free T3 in addition to TSH is recommended.

Creatine Kinase

Creatine kinase is an enzyme that can be analyzed to see how the body responds to muscle damage during high training loads. It peaks approximately 2-4 days after an intense training session, so the testing window is important for this blood marker. Persistently high creatine kinase levels have been linked to muscle pain, tenderness, weakness and an increased risk of injury.

Ongoing creatine supplementation can falsely elevate creatine kinase levels, so it is important to understand the supplements used by the athlete when interpreting laboratory results.

Ferritin

Ferritin is a biomarker that is the best indicator of iron status in the body. Iron supports metabolism and helps form hemoglobin to carry oxygen to tissues, which is important for optimal performance as an athlete. Low iron levels are more common in menstruating female athletes and have been associated with fatigue, a high risk of injury and an elevated resting heart rate.

Male/Female Hormone Panel

Overtraining, especially without adequate recovery and sufficient calorie intake, can lead to a high-risk condition called Relative Energy Deficiency in Sport (RED-S). This condition increases the risk of injury, illness and hormonal dysfunction, especially in young female athletes. Understanding sex hormone levels can help reduce the risk of RED-S and align athletes' training, recovery and nutrition plans with their performance goals.

Omega-3 Index

Omega-3 fat levels are important in controlling inflammation related to heavy training loads and have been associated with better recovery and reduced post-workout muscle soreness in athletes. The omega-3 index can provide information about an athlete's inflammatory status and help guide recovery plans to support optimal performance.

Using Laboratories to Improve Performance in Athletes

By using data from functional blood tests, athletes can gain a personalized understanding of their nutrition, recovery needs and the supplements they need to optimize their performance.

Nutrition

An important component of optimal performance for an athlete is a nutrition plan made up of varied, high-quality whole foods with calories appropriate to the athlete's training load. If blood tests show deficiencies in certain vitamins or minerals, such as iron or vitamin D, a nutrition plan that includes more whole-food sources of these micronutrients can help the athlete meet their needs.

Ensuring adequate protein intake is important for athletes, because protein is essential for muscle repair and recovery (training adaptations) and is necessary to maintain muscle mass and an appropriate body composition. Inadequate protein intake can lead to consequences such as an increased risk of injury, decreased muscle mass and strength, and reduced athletic performance. It can also have effects such as low iron levels, changes in cortisol and sex hormones, and changes in thyroid function, because protein is necessary for hormone production. Athletes may often require more protein than the amount recommended for the general population, and some studies point to 2 grams per kilogram of body weight to promote optimal athletic performance.

Depending on the type of sport and training load, athletes may need different carbohydrate intakes for optimal strength and performance. A light recovery day may require only 2-3 grams of carbohydrate per kilogram of body weight, while Ironman athletes or other endurance athletes may need three times this amount on typical long training days. Low carbohydrate intake can contribute to changes in muscle strength and power, reduced endurance, and temporary fluctuations in blood laboratory values such as thyroid hormone levels and cortisol.

Adequate fat intake is also important for athletes, particularly with regard to inflammation and hormone production. Moderate fat intake is associated with better testosterone levels, and higher intake of omega-3 fats reduces inflammation and supports recovery. Athletes who need to reduce body fat may consider supplementing with omega-3 fats.

Supplements

By using functional medicine blood tests as part of an athletic training program, an athlete can gain a personalized understanding of which supplements they need to support their training and performance goals.

Blood tests that indicate a high stress load and overtraining - for example, high cortisol, low thyroid or other hormone levels, and low levels of micronutrients such as zinc or iron - can, alongside appropriate nutrition and an optimal training/recovery balance, be translated into a supplement routine that supports these systems. Adaptogenic herbs such as ashwagandha can be an excellent addition to help support stress levels and optimize performance.

Some supplements, such as antioxidant supplements like high-dose vitamin C or vitamin E, can affect muscle damage levels, which are actually beneficial for certain sports such as bodybuilding. As a result, an approach that prioritizes performance nutrition and guides supplements with blood tests is the most evidence-based approach for most athletes.

Nutrigenetics

Nutrinext - Sport & Wellness Complete belongs to the field of nutrition aimed at both professional and amateur athletes. Examining the genetic profile helps increase performance level and reduce injuries.

Summary

Blood tests can help optimize athletic performance by adding a personalized layer to an athlete's training, nutrition and recovery plan. Using data from blood tests that examine micronutrients, hormone levels and inflammatory markers can help ensure that an athlete's nutritional needs are being met and that they are adapting appropriately to training, and can help adjust nutrition and supplement plans for optimal health. You can review the check-up panel we have prepared for athletes.