Which Supplements Should Runners Take?
It is no secret that running is tough on the body. The immune, skeletal, and endocrine systems all take a beating during a typical training cycle. Fortunately, there are ways to increase your body’s ability to sustain the damage by taking nutritional supplements. The most beneficial supplements for runners are described below.
One of the most common deficiencies in runners – particularly females – is iron. While females have an obvious reason for iron deficiency (menstruation), studies1 have indicated that all runners are placed at a greater risk of developing anemia. Iron is important for many critical functions, such as shuttling oxygen throughout the body. When a runner is deficient in iron, fatigue, muscle weakness, and loss of motivation are common.
A recent study2 showed that only 4 weeks of IV iron supplementation in fourteen runners resulted in reduced perceived fatigue during exercise and improved mood. The most common form of iron supplementation is ferrous sulfate; however, this may cause constipation in some people. A more stomach-friendly version is iron bisglycinate, which is formulated with glycine for better absorption. Runners should consult with a physician before taking an iron supplement, as too much iron in the body can cause symptoms similar to anemia.
One macronutrient that runners often lack in their diet is fat – especially in a healthy form. Generally, the American diet is filled with omega 6 fatty acids, thanks to common sources such as vegetable oils and nuts. However, omega 3 fatty acids are extremely important. The omega 6 to omega 3 fatty acid ratio3 should be 2:1 to 4:1, but instead, most Americans consume fatty acids in a 15:1 ratio, which can result in inflammation and chronic disease.
Fish oil (particularly cod liver oil), is a high source of omega 3 and can better improve this ratio, which is necessary for bone, brain, and immune system health. Look for a supplement that contains at least 500 mg of combined DHA and EPA.
Most runners mistakenly believe they receive enough Vitamin D during their daily runs. However, many people suffer from Vitamin D deficiencies, which can lead to increased risk of stress fractures, muscle weakness, and fatigue. One study4 indicated that 42% of runners had insufficient Vitamin D levels, while 11% were deficient. Further, insufficient/deficient levels of the vitamin also correlated with inflammatory biomarkers.
In fact, numerous professional athletes have linked injury to Vitamin D deficiency, leading to increased awareness about the necessity of this vitamin. As with any supplement, athletes should have a blood test before starting supplementation, but typically 1000 – 2000 IU is recommended.
Vitamin D and calcium deficiency often go hand in hand, as Vitamin D aids in calcium absorption. Without adequate calcium, muscles do not function properly, leading to cramping, and and increased risk of developing stress fractures. A study published in Journal of Bone and Mineral Research5 indicates that female naval recruits (n = 5,201) had a 20% reduced risk of developing stress fractures during basic training when provided calcium and Vitamin D supplements versus their placebo-receiving cohort.
Athletes should only take calcium supplements under supervision from a medical professional, as too much of this mineral can negatively affect cardiovascular health.
Probiotics are all the rage lately, with products such as kefir, kombucha, and fermented vegetables being highly touted for their beneficial bacteria. A growing body of research6 has linked endurance sports with lack of adequate microflora in the gut, which can lead to a host of performance inhibiting symptoms.
Symptoms include weakened immune system, chronic inflammation, gastrointestinal problems, and general malaise. Probiotics supplementation can reverse this problem, and studies performed link probiotic use in endurance athletes with improved performance7. Although an adequate amount of probiotics can be attained from food sources (particularly yogurt), taking a supplement in pill or powder form is also beneficial and requires no medical supervision.
Amino acids are the building blocks for life and are particularly important for muscle and immune system support. Runners are notorious for breaking down both of these systems, which is why l-glutamine is important.
One study8 indicated that marathon and ultramarathon runners experienced the highest number of infections after races due to a 20% decrease in plasma glutamine levels. However, glutamine supplementation significantly decreased the number of infections reported after exhaustive exercise among these athletes. L-Glutamine is available in powder or tablet form, and should be consumed immediately post-exercise in a dosage of 2 – 4 g.
Every athlete knows that protein is essential during periods of heavy training. After all, without protein there would be no muscle repair, and without muscle repair the body simply could not function. Unless you have the time to devote to strict meal planning, chances are you do not consume enough protein for your exercise needs, which is why protein supplementation is important.
There are three common sources: whey, soy, and rice. Although protein bars are one way in which athletes can get a quick protein fix, they often contain unnecessary ingredients, such as sugar. Powdered protein is the best option, which can conveniently be mixed into a shake.
Whey protein is largely considered to be one of the best supplemental forms of this macronutrient due to branched amino acids9 that quickly deliver nutrients to muscles for efficient recovery. However, whey protein is not appropriate for those who are lactose intolerant or vegan. Soy protein may be a better option, as it also is a great source for amino acids.
One potential concern among athletes is that non-genetically modified soy protein is difficult to find and can be expensive. For this reason, rice protein is also recommended. Rice protein is made from brown rice that has been chemically separated from the carbohydrate portion of the grain. It is easy to digest and great for vegan and vegetarian athletes, or those who suffer from food sensitivities.
Great news for runners is that everyone’s favorite supplement, caffeine, has numerous positive implications for running performance. Caffeine boosts the central nervous system10, leading to improvements in focus, alertness, and acuity, which are especially important for early morning races. Popular forms of caffeine such as coffee and green tea have also been shown to provide antioxidants and polyphenols – both of which have been shown to have healthy benefits. During exercise, caffeine has been observed to provide a slight increase in performance.
Among 30 runners, those who consumed caffeine11 prior to a 5k time trial improved times by 1% compared to a placebo group. Consuming caffeine post-exercise also has benefits. Athletes that took in both caffeine and carbohydrates following exhaustive activity improved glycogen storage by 66%, compared to when only carbohydrates were consumed. The only caveat? Five to six cups of strong coffee were required for these results.
What’s your take on these supplements? Have you found the magic substance that boosts your muscles and transforms you into a superhuman? Share your ideas, I’d really love to know what you think!
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