Supplements for Runners

Runners are always looking for a way to maximize performance. Whether it is through the addition of strength training, adding recovery movements, managing rest, or optimizing nutrition tactics, there are ways to get faster other than just running. Of course, the backbone of strength, speed, endurance, and recovery is nutrition. Food is the fuel that makes the car go, and if there is not enough gas in the car, you cannot get very far. That is why the first thing I like to work on with runners (and all athletes) is foundational fueling with carbs, protein, fat, fiber, and fluid. I already talked about this at length in my former blog post “Running Form and Recovery,” but to summarize the nutrition needs for runners:

1. Carbohydrates: Runners need between 3g/kg (for those recreational runners who run for ~30 minutes a few days per week) and up to 12 g/kg (for marathoners or ultramarathoners in peak training. These should be spread throughout the day in meals and snacks  to promote stable blood sugar and energy levels throughout the day.

2. Protein: To recover the muscles, runners need 1.2-1.6 g/kg protein spread out through various meals and snacks.

3. Fats: Make it a goal to include them at every meal to help with flavor, fullness, and obtaining adequate energy intake. Watch out though, too much fat before a workout can cause digestive upset, so make sure to limit it in the 3 hours before you go out for a run. 

4. Fiber: Recommendations for runners are no different than the average person; that is, 28 g/day for women or 32 g/day for men spread throughout the day. Keep in mind, however, that the timing of this is important. It may be best to avoid fiber (AKA fruits, nuts, whole grains, and veggies) for the 3 hours before workouts to prevent GI distress. 

5. Fluid: Aim to drink 0.5 oz per pound of body weight PLUS 5-7 ml/kg 4 hours before activity PLUS 16-24 oz per hour during activity PLUS fluid after to replace fluid losses from sweat during exercise. Fluid needs should be individualized, so work with an RD to determine your own.

6. Micronutrients: While it is important to have a balanced diet that provides adequate levels of all vitamins and minerals, iron and vitamin D have direct impacts on performance and injury prevention.  

Eventually, however, once runners feel they have the foundations down, they start asking about supplements. There is something exciting about supplements - some may think of them like the magic pill that will make them go from a recreational to a professional level runner. Do not get me wrong, ergogenics supplements certainly can enhance performance as I will discuss, but which ones are worth it? In this blog, I will summarize common supplements that may or may not be beneficial for running performance.

Sports Foods

I decided to categorize sports gels, chews, bars, drinks, electrolyte supplements, and protein supplements in one category because they check at least one of the six foundations of good nutrition above, and therefore have the most evidence to support their use. Sports gels, chews, bars, and drinks are meant to be used before or during activity to maintain blood sugar levels and prevent the body from dipping too far into its glycogen stores (in other words, “hitting the wall”). Evidence supports eating 60-90 grams/hour of carbs for runs lasting longer than 1 hour. Sports drinks and electrolyte supplements are used during activity to manage fluid losses from sweat and prevent dehydration. As I mentioned above, working with an RD to determine your exact fluid and  electrolyte needs is essential because of how individualized these needs are. Finally, protein bars or supplements can be used to help repair the muscles after running. Protein drinks specifically can be helpful if you struggle to get 20-30 g of protein after your workout due to a poor appetite, as it is often easier to drink compared to eating after a hard effort. 

Just because these are more “whole food” options however, does not mean that they are not subject to the same mis-labeling and potential contamination issues that other supplements have. A general rule of thumb is this: if a product has a “supplements facts” label, it is considered a supplement, in which case you will want to make sure it is third-party tested. More on that later. If a food label says “nutrition facts” it is considered a food and has undergone rigorous testing by the FDA, and does not need to undergo third-party testing to be considered safe for sport.

Collagen and Vitamin C

You may have heard of collagen from the beauty industry due to claims that it strengthens connective tissue, thereby resulting in stronger and healthier hair, skin, and nails. Well, these claims translate to athletes too. Our tendons and ligaments are made of collagen, researchers questioned if supplementing would improve connective tissue health. They found that taking 15 g/day of collagen hydrolysate with a source of vitamin C (sourced from something like juice or a piece of fruit) one hour before exercise translated to greater tendon strength and less joint pain.^1,2

It is worth mentioning that taking this supplement will not fix joint pain or completely prevent you from developing an injury, however it may reduce the likelihood of developing a soft-tissue injury and enhance injury recovery when combined with proper foundational nutrition, training volumes, and recovery tactics. We also get plenty of collagen from our foods, like meat with connective tissues, chicken or fish with skin, and bone broth. 

Omega-3 Fatty Acids

Next, omega-3 fatty acids have also been found to be beneficial for reduction of muscle soreness after exercise. While the mechanism of this makes sense, as omega-3 fatty acids are known to be anti-inflammatory, this may be an oversimplification, as the literature is not a 100% consistent finding and low levels of omega-3 fatty acids are not necessarily associated with increased inflammation or decreased performance.² 

While in general it is not too risky to supplement with omega-3 fatty acids at a safe level (I recommend 2000 mg to my athletes), athletes should also weigh the pros of a supplement which may not have too much of an impact on running performance, with the potential risks associated with it, such as potential contamination, unpleasant taste, stomach upset, diarrhea, reflux, and cost (oftentimes $30-40 for a 1 month supply). It is never wrong, and oftentimes more beneficial, to get your omega-3 from food sources such as salmon, mackerel, sardines, flax seed oil, walnuts, or fortified foods such as eggs and dairy.² 

Tart Cherry Juice

Another supplement that has gained popularity recently is tart cherry juice. However, there is little evidence that tart cherries or their juice result in meaningful performance benefits. In fact, one could likely attribute any benefits seen in performance to the carb content of this drink, rather than any “special” properties. Over the long term, however, performance benefits may be seen through this supplement’s ability to improve recovery, thanks to the polyphenol content, which directly decreases inflammation in the body.² This means less exercise-induced muscle damage, less muscle soreness after intense bouts of exercise, and more ability to recover between strenuous sessions.³ 

What does this mean for runners? Well, cherry juice likely is not beneficial for performance for endurance athletes who are only competing in one race every couple of months, but it may benefit track athletes who run multiple events over multiple days because it will enhance recovery, allowing runners to get more out of each race. Runners can drink 8-12 oz of tart cherry juice (or 30 ml of concentrate) 4-5 days before events or for 2-3 days after to see benefits.² 

Creatine

Creatine has been popularized mostly among body-builders for its known ability to enhance muscle protein synthesis and improve performance between repeated high-intensity bouts of exercise (think sprints in team-based sports like soccer or lacrosse).² When it comes to endurance running, creatine is likely not as beneficial. Even though someone who is training for a marathon may be running at a high-intensity, the use of creatine may actually be detrimental due to the known side-effect of water retention. Additionally, while strength training is certainly beneficial for runners, muscle growth and definition is likely not the goal if you are prioritizing running. On the other hand, if someone is primarily weight-lifting and recreationally running to maintain cardiorespiratory fitness, creatine may be beneficial for muscle growth and performance. Work with an RD to determine the proper dose, timing, and administration of this supplement.

Caffeine

Caffeine is a supplement that may have more immediate impacts on performance thanks to its ability to decrease perceived exertion. Most research supports taking 3-6 mg/kg from a pill or powder ~60 minutes prior to exercise for maximum benefit.² The recommendation for a pill or powder form likely comes from the need to reduce fluid consumption prior to an event, especially running. No one wants to stop to use the bathroom in the middle of a long run or race! 

Notably, there does not seem to be a greater benefit from taking greater than the recommended dose, and in fact taking greater than 6 mg/kg may be deleterious in effect, as too much caffeine can increase anxiety and jitteriness, ultimately causing one to lose focus and impair performance.² 

You may have noticed that many running gel companies have started engineering their gels to have caffeine in them. That is because caffeine can also be used during exercise to enhance performance. Companies such as Maurten, Gu, SIS, Precision, and Honey Stinger offer various dosages of caffeine (usually between 32-100 mg per gel) because caffeine is shown to be most effective when taken with carbohydrates during activity. Given this large range of caffeine inclusion in gels, it is clear there is no set recommendation for how much caffeine is best to take during exercise, but my recommendation would be to not exceed a total amount of 3-6 mg/kg between your pre-exercise and intra-exercise caffeine to prevent adverse effects such as digestion upset, jitteriness, loss of focus, heart palpitations, and ultimately a decrease in performance. 

Not to mention, caffeine tolerance needs to be built up, and even if we are within the recommended range of 3-6 mg/kg, if you increase from only having a cup of coffee at home before a run (which usually provides ~80-100 mg of caffeine) to having an energy drink (which can contain up to 300 mg of caffeine) before a race, you will likely feel the negative effects. As with anything food or supplement, never try nothing new on race day! Given that caffeine tolerance is very individualized, it is recommended that you work with an RD to determine the right dose for you.

Beet Root Juice or Dietary Nitrates

Beet root juice is high in dietary nitrates, a substance which our bodies convert into nitric oxide. Other root vegetables contain nitrates, but beet root juice is the most widely studied thanks to its high bioavailability of this compound in beets specifically.⁴ Nitric oxide acts on our blood vessels to make them larger, increasing blood flow and oxygen delivery to the muscles, while also decreasing the amount of oxygen that our body uses during exercise, which increases time to fatigue and overall endurance performance.^2,4 This may not benefit all runners however, as studies vary in demonstrating effects between non-trained and trained athletes, with many studies showing larger effects on untrained athletes.⁴ So, while beet root juice may be beneficial for a runner doing their first 5K, it may not be beneficial for the seasoned marathon runner.

You may be wondering, “how much juice do I need to drink?” The answer is that we don’t really know. The concentrations that have been studied thus far are 4 mmol, 8mmol and 16 mmol beet root juice, however the nitrate content of these juices varies widely, so you will likely not be able to determine the nitrate concentration in the juice you buy at the grocery store.^5,6 Studies have recommended ~300-500 ml of beet root juice or 70-140 ml of concentrated beet juice 2-3 hours before exercise.⁵ I will let you weigh the risks and benefits of drinking that volume of juice before a workout. Because of this conundrum, companies have started making beet root powder for a more concentrated version. For example, the company Humann, requires mixing 1 tsp of the powder into 4-6 ounces of water.  Of course, because the beets in the powder are grown the same way as the beets in the juice, the nitrate content varies widely, so there is risk that you may not be getting the effective minimal dose or getting a higher dose than you bargained for. In fact, many supplements do not advertise the nitrate content of their product, nor do they have to advertise this information. With that, the risks of buying a supplement that does not contain enough nitrates is really just a financial risk, where as if the dose is actually higher it may cause reductions in blood pressure in a population who likely already has low blood pressure, resulting in possible dizziness or fainting. All this to say, while beet juice is a promising supplement to enhance performance, we must, as always, consider the potential benefits with the associated risks.

Supplement Safety

In my experience, these are the supplements that I am most commonly asked about by runners. Each runner is unique in their needs and may require different uses of supplements at different times in their training cycles. Regardless of the supplement routine, my biggest concern is that the supplement is safe because as I alluded to earlier, supplements are not tested by the Food and Drug Administration (FDA) and can be contaminated with banned substances, which is especially important for college and professional athletes, but really for anyone, as contaminants can have direct impacts on your health. There are companies who do test supplements for contaminants, such as The National Sanitation Foundation (NSF), US Pharmacopoeia, Consumer Labs, Informed Choice/Sport, and Banned Substances Control Group (BSCG). 

Still confused on which supplements are safe and which aren’t? Wondering which supplements might benefit your running performance? An RD at SkimWellness can help you navigate the confusing world of supplements, and determine which, if any, may be helpful to include on top of a balanced diet.

References

1. Shaw G, Lee-Barthel A, Ross ML, et al. Vitamin C-enriched gelatin supplementation before intermittent activity augments collagen synthesis. Am J Clin Nutr 2017;105:136–43.doi:10.3945/ajcn.116.138594

2. Maughan RJ, Burke LM, Dvorak J, et al. IOC consensus statement: dietary supplements and the high-performance athlete. British Journal of Sports Medicine 2018;52:439-455.

3. Levers, K. et al. (2016, May 26). Effects of powdered Montmorency tart cherry supplementation on acute endurance exercise performance in aerobically trained individuals. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4880859/

4. Tian, C., Jiang, Q., Han, M., Guo, L., Huang, R., Zhao, L., & Mao, S. (2025). Effects of Beetroot Juice on Physical Performance in Professional Athletes and Healthy Individuals: An Umbrella Review. Nutrients, 17(12), 1958. https://doi.org/10.3390/nu17121958

5. Wein, D. A. (2013). Beetroot juice supplementation and exercise. Personal Training Quarterly, 1(1).

6. Gallardo, E. J., & Coggan, A. R. (2019). What's in Your Beet Juice? Nitrate and Nitrite Content of Beet Juice Products Marketed to Athletes. International journal of sport nutrition and exercise metabolism, 29(4), 345–349. https://doi.org/10.1123/ijsnem.2018-0223