Preparing for a Blood Draw: 8 Essential Tips on Exercise Before Blood Tests and More

Get detailed advice on how to prepare for a blood test. We address common concerns such as whether you need to fast before or if you can work out before blood tests, ensuring accurate and reliable results.

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By Staff Writer
Lucia Gcingca
Edited by Lucia Gcingca

Published March 6, 2024.

a group of women doing yoga in a gym - Exercise Before Blood test & More

An astonishing 2 billion blood tests are conducted in the US each year. [1] Getting your blood drawn, though typically quick and painless, often comes with stress and confusion. Many people grapple with questions like how to prepare, what to bring, and where to go, as these aspects might differ with each test.

Amidst these considerations, one common query is about exercise before a blood test. It's worth mentioning that understanding the implications of exercising before blood work, as well as other factors listed below, is essential for accurate results.

So, can you exercise before a blood test, and if so, how long should you not work out before a blood test? Should you take supplements before a blood draw? And what about prescription medicine? Let's find out—here’s what you need to know to prepare for your blood draw with InsideTracker.

Note: InsideTracker's offerings, excluding Blood Results Upload and Home Kit, require a phlebotomist's expertise for blood collection, either at a laboratory or your home. [2]

7 key steps before your blood draw

Should you exercise before blood tests and what are some other key considerations to keep in mind while you prepare for your blood draw? Here's a quick recap.

  1. Do not engage in strenuous exercise for two days before the blood test.
  2. Fast for at least 12 hours before your draw.
  3. Schedule your blood draw for the morning.
  4. Do not drink any alcohol for at least 24 hours before the InsideTracker blood test.
  5. Do not take supplements within 24 hours of your blood draw.
  6. Continue medication use as recommended by your physician.
  7. Drink extra water before the blood test to ensure proper hydration.
  8. Bring a photo ID to any tests conducted at Quest Diagnostics.

Note: If you’re getting lab work done through your doctor, please follow their instructions. This article presents guidance for those who have purchased an InsideTracker plan.

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1. Do not engage in strenuous exercise for two days before the blood test

Performing intense exercise the day before your draw may result in elevated levels of blood biomarkers like the liver enzymes ALT and AST, creatine kinase, and hsCRP—which are related to muscle breakdown and inflammation. [3,4,5] While we recommend a 2-day rest period for most people, beginner weight-lifters should avoid weightlifting before a blood test for about 7 days.

2. Fast for 12 hours before the blood draw

Part of your blood test preparation is to fast for at least 12 hours before your test, otherwise, nutrients and ingredients in food are going to be absorbed in the bloodstream and can affect certain blood test results. So, fasting helps you get the most accurate biomarker measurements from your blood draw. While all food and beverages are off the table during this fast, black coffee is ok.

3. Schedule your blood draw for the morning

As it is recommended to only drink water and fast before a blood draw, fasting overnight is often the easiest choice for most people—so, we recommend scheduling your test for the morning. In addition, many biomarkers are best measured in the morning.

» Curious about what your lab results mean for your health? Here's how to read your blood test lab results

4. Do not drink any alcohol for at least 24 hours before the blood test

The reason you can't drink alcohol before your blood test is that drinking alcohol the night before your blood test can acutely raise blood sugar (glucose), fat (triglyceride), and the liver enzyme GGT. [6] We recommend not alcohol before blood work for 24 hours for the most accurate results.

5. Do not take supplements within 24 hours of your blood draw

Taking supplements can also acutely impact some of your biomarkers. We suggest refraining from supplements for 24 hours so that your levels reflect an accurate baseline for your body. If you receive vitamin or mineral IV infusions, remember that this causes blood levels to remain elevated for a few months. If you're on Biotin supplements, don't take them for at least 72 hours before your test.

» Ready to take charge of your health? Order your blood test online now

While it’s a good idea to refrain from taking supplements before your blood draw, you should continue to follow your physician’s recommendations for medications—both over-the-counter and prescription.

Note: Pain relievers like Ibuprofen and other NSAIDs may acutely impact the liver enzyme GGT. [7,8] For some people, platelets (which work to clot the blood) may appear slightly lower than normal, as many of these medications work by thinning the blood.

7. Drink extra water before the blood test to ensure proper hydration

Drinking water before your blood draw is essential, as more water increases blood volume. Being sufficiently hydrated can make it easier for the phlebotomist to find veins, thus quickening your appointment.

» Discover how your menstrual cycle affects blood test results

8. Get blood drawn at a Quest Diagnostics lab

So you've made your appointment to get blood drawn at a Quest Diagnostics lab. Now, all you need to bring for your blood test is a photo ID. That’s it! You've already paid for your test with InsideTracker, so no additional payment is required at the lab. And you don’t need any insurance information—the lab will already have the relevant information that tells the phlebotomist which tests to draw.

Good to know!

If you live in the United States or Canada and you prefer to have a phlebotomist come to your house to draw blood, you can schedule a mobile blood draw, i.e., blood draw at your home by logging into your account, clicking “Use test” on the top right of the screen, and then selecting “Schedule my test.” From there, you’ll receive instructions on what to expect during the blood draw.

Drawing to a close

Now, all that’s left is to get your blood drawn! Set an appointment reminder on your phone, and remember these key takeaways: fast for 12 hours beforehand, avoid strenuous exercise and alcohol for 24 hours, and put a pause on supplements. Stay hydrated and stick to your doctor's advice. With these simple steps, you're all set for a successful Inside Tracker blood test.