After the BolderBoulder 10K in May, participants meandered through a postrace festival lined with vendors offering samples of coffee and fare from local food vendors.

They could also treat themselves to an IV drip.

No, it wasn’t from the medical tent. At the Onus iV Hydration clinic’s mobile unit, runners had the option to get a saline drip infused with vitamins, minerals, and pain medications with the hope of jumpstarting the recovery process.

Clinics like Onus iV Hydration—which formed its business in December 2014, takes its portable facility to races around Colorado, and will open its brick and mortar location next month in downtown Denver—are beginning to pop up around the country in cities like Chicago and New York City.

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The service resembles clinics like Hangover Heaven in Las Vegas, which markets drips to drinkers with morning-after regrets. Some spas also offer drips to help people beat jet lag or the flu.

The practice of using IVs as a means of rehydration for athletes isn’t new. Healthy elites have reportedly gotten saline-only drips for recovery for at least 20 years. What sets Onus iV Hydration apart is that it provides nutrient-enhanced drips targeted at regular endurance athletes looking to speed recovery.

While there is some research, there is currently no concrete evidence to support the claim that getting a drip speeds recovery; some experts think it’s no more effective than taking ibuprofen with a sports drink. But if you come across a clinic like Onus iV Hydration after a race in the future and you’re tempted to try it, here’s what you should consider before getting hooked up.

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THE IDEA BEHIND THE BAGS

When it comes to recovery, the faster an athlete can rehydrate, the better. Muscle recovery is delayed if you’re dehydrated. Replenishing fluids after a tough effort can be tricky, however. During hard workouts or races, blood flow to the stomach is redirected to the muscles. This reduction in blood flow to the stomach results in a decrease in the ability to digest and absorb nutrients. That’s one reason why, when runners chug a sports drink right after a race, they sometimes throw it right back up.  

If the drink does stay down, only 50 to 60 percent of its vitamins and minerals are absorbed by the cells, nerves, and muscles that need them, according to Dr. Benjamin Wilks, an emergency medical physician and co-owner of Onus iV Hydration.

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Because IVs bypass the GI tract, rehydration can happen at a faster rate without the risk of vomiting, and all of the nutrients in the drip are placed directly into the blood stream.

“Imagine trying to ingest a gallon of water after a race,” Wilks said. “It’s pretty much impossible, at least in the timeframe we would be able to rehydrate someone intravenously.”

Carwyn Sharp, Ph.D., a Colorado Springs-based exercise scientist who has studied the impact of nutrition on recovery in athletes, said oral hydration is sufficient for proper recovery in most cases. But when an athlete is very dehydrated, he does agree that IVs can boost recovery.

While Sharp hasn’t tried a clinic like Onus iV Hydration, the 2:46 marathoner did once require a saline drip (a blend of salt and water) in the medical tent because he didn’t hydrate properly during a marathon.

“After an hour or so, I was walking around the expo feeling 100 percent, like I hadn’t even run the marathon,” Sharp said.

Clinics like Onus iV Hydration offer a menu of drips that range from a basic bag of saline to a cocktail of vitamins, minerals, and medications, which is marketed to boost recovery even more. Customers can also pick and choose which nutrients they’d like pushed through the IV.

Here’s a look at what’s inside Onus iV Hydration’s “Dominate/Rebound” bag, which is used for recovery after races or hard workouts. 

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1. DEXTROSE 1L

What is it? A sugar that is easily digestible by the body.  

Sharp’s take: “This is very commonly used in IV drips. The molecule is rapidly taken up into muscles and aids in restoring glycogen stores and providing energy for the recovery processes such as building new proteins.” 

Does it aid in recovery? YES

2. B12 1 CC

What is it? A water-soluble vitamin that maintains the body’s nerve and blood cells.

Sharp’s take: “The idea behind it is if I give you more B12, your body will have a better capacity to generate and use energy. It only seems to work if your body is deficient. If your body doesn’t need it, it’s flushed from the system. If you eat lots of fruits and vegetables, you’re likely not deficient.”

Does it aid in recovery? NO

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3. TORADOL 1 CC AT 20MG/ML

What is it? A strong anti-inflammatory drug that is in the same family as ibuprofen and naproxen. 

Sharp’s take: “It’s for moderate to severe pain and is often given to people who are having surgery. I’m a big believer that the pain you get from running tells you something. If it’s excessive—beyond what you’d normally feel after a marathon—you’ve done too much. There is also research that shows that ibuprofen and acetaminophen impair the recovery process, but I’m not aware of research that’s been done on Toradol.”

Does it aid in recovery?  NO

4. Calcium Glunconate 2CC at 10 percent

What is it? A medication that is used to prevent and treat calcium deficiencies.

Sharp’s take: “If you’re prone to kidney stones, taking in too much calcium can cause them. This is particularly true for those people who are dehydrated.” 

Does it aid in recovery?  NO

5. AMINO ACIDS 3 CC (optional)

What is it? An organic compound that helps build muscles by forming proteins.

Sharp’s take: “Additional amino acids may assist in the recovery process. At certain times, like after stress or chronic exercise, your body might not be able to make enough. Your body can make enough most of the time, however.”

Does it aid in recovery? YES

 

WHAT THE RESEARCH SHOWS (OR DOESN’T)

The doctors who head IV therapy clinics readily admit there’s very little research to back up their practices.

Wilks acknowledges giving athletes enhanced infusions hasn’t been rigorously tested.

“Before anything is put into practice, it needs to be tested for years before it becomes standard of care,” Wilks said. “But there are always things that people do that are not rigorously tested that claim to improve your health.”

Some physicians, including Jack Dybis, D.O., a general and trauma surgeon who founded IVme Hydration Clinic in Chicago in 2012, argue research doesn’t need to be done to prove it works—the effects of IV hydration are the same as oral hydration, but drips speed up the process.

“It’s more about what the patient feels,” said Dybis. “It does make you feel better. I give fluids to people every day, so I see how it affects them. But it’s not a medical necessity, so people aren’t doing research on it. It’s a subjective thing.”

There is some research—but it doesn’t reveal much.

A study conducted after the 1991 Rotterdam Marathon involved giving “experienced male runners” saline drips. The results showed no substantial improvement in the rate of recovery or pain and stiffness levels when compared to athletes who did not receive an infusion.

Nineteen years later, a review article published in Sports Health summarized what research has been done regarding IV fluids for rehydration. It concluded that any differences between IV and oral hydration were negligible, while post-workout infusions didn’t translate into any health or performance benefits during succeeding exercise.

Despite these insignificant findings, Wilks said his clinic has yet to receive negative feedback and that customers regularly say they feel amazing afterward.

One such runner is Mark Wolcott, a 47-year-old from Cheyenne, Wyoming. He’s run a half marathon a month for nearly two years and holds a 2:21 personal best at the distance. After the Colfax Half Marathon in May, he got a drip from Onus.

“I wasn’t expecting to feel as good as I did,” said Wolcott, who said he felt alert rather than worn out during his 2-hour drive home from Denver. “Usually after a race, I don’t want to be bothered by anybody. [After the drip,] I felt happier and more energetic. That night when I went to bed, I had no pain.”

When asked if there’s a possibility of a placebo effect with IV drips for recovery, Sharp said, “I think there’s always a possibility of that when you know you’re getting a treatment.”

IS IT CHEATING?

For runners like Wolcott who aren’t competing for prize money or awards at a championship-level event where competitive advantages matter, a recovery drip won’t have a huge impact.

In 2005, the World Anti-Doping Agency (WADA) took its stand on the treatment, prohibiting the voluntary use of IV fluids—both in and out of competition—except when it is required for hospital admissions, surgical procedures, or clinical investigations. The organization claims IVs could change blood test results, mask urine tests results, or administer prohibited substances that could be more easily flushed from the body.

The U.S. Anti-Doping Agency (USADA) follows the WADA Prohibited List and also bars IVs.

At races certified by International Sports Federations and National Governing Bodies (NGB), all runners fall under USADA’s guidelines and would be in violation if they got a non-medical IV.

“USADA’s limited resources are obviously focused primarily on top level athletes,” reads USADA’s website. “However any athlete competing in a race that falls under an NGB’s jurisdiction or that has a short term or long term NGB license can be tested by USADA.” 

WHAT TO EXPECT

At clinics like Onus iV Hydration and IVme Hydration Clinic, registered nurses and paramedics practicing under the supervision of a licensed doctor typically administer drips. Depending on which state the clinic is in, doctors may or may not need to be present, and often times, the nurses or paramedics make the call as to whether a runner is a good candidate to receive IV therapy.  

To determine if a runner can safely get an IV, the patient fills out a detailed medical history and receives a physical check-up. Some conditions—like being pregnant, allergic to a specific medicine, or susceptible to kidney stones—might mean a runner would be turned away or offered a different IV therapy that would not be contra-indicated based on their medical history.

If a runner proves to be a good candidate, he or she signs a liability waiver that outlines the potential risks involved.

“They went over everything, from where they got their needles, what was in the bag,” Wolcott said of his experience with Onus iV Hydration. “I trusted them because each [shot to be pushed through the IV] had a description of what it was. At least three or four times, they asked if I had any questions or concerns prior to getting my IV.”

From start to finish, it takes about an hour to go through the intake process and receive a drip. Patients won’t be stuck staring at stark hospital walls while they get infused either—clinics and mobile units often resemble a spa, complete with cushy chairs and TVs.

A basic bag of saline will run you $65 at Onus iV Hydration, and other boosted cocktails are usually $100 or more per session. Kristy Anderson, co-owner of Onus iV Hydration clinic said runners can prepay at the expo for treatments offered at Onus iV Hydration’s mobile unit postrace.

Runners who partake face the same risks as you would getting an ordinary IV: bruising, swelling, and a chance for infection and redness at the site of the injection. Wilks said the most serious possible negative outcome is a severe allergic reaction, so Onus iV Hydration makes sure to have an EpiPen nearby.

The clinics interviewed also said they would not treat anyone who is in actual distress or in need of a higher level of care. When Onus iV Hydration’s mobile unit is on-site at a race, they help runners get to the medical tent if they deem something is emergently wrong with them.

“In no shape or form are we providing a medical service,” Wilks said. “If someone is profoundly dehydrated or having episodes of heat stroke or hypothermia, we say, ‘Listen, this is not the right place for you. You need to go to the EMS tent.’”

DRIP? OR NO DRIP?

When compared to traditional recovery by way of sports drinks, an ibuprofen, and some extra rest and relaxation, are IV drips worth trying? It depends. Will it revive you after a hard race in a fraction of the time? Maybe. Will it hurt you? Probably not.

“There are so many whole foods and rehydration and recovery beverages out there that cost less than $5 that include dextrose, amino acids, vitamins that I would choose as the better option almost all the time,” said Sharp, who recommends runners who are interested in the treatment do their homework before getting an IV. “This may be a possible recovery tool, but for me, as a nutritionist and coach, there isn’t the science to convince me.”

Still, Wolcott said he’d consider trying it again.

“For someone my age who is not a fast runner who would be subjected to the heat during a 13.1-mile race, I think this is something that would be beneficial,” Wolcott said.  

“The BolderBoulder, for us, was a great way to showcase the service we provide, not necessarily to say it’s our target market,” Wilks said, although about five people received drips that day. “A 10K isn’t the distance where you’d need our service. Treatments are ideal for marathon runners, Ironman triathletes, long distance cycling, running or adventure races.”

Sharp said he believed if anyone truly needed an IV after a race, it would be runners that are severely dehydrated and in need of medical attention.

This article originally appeared on RunnersWorld.com.