Can You Eat Spinach For Muscle Growth

Written by Dr. Steve Chaney on . Posted in Exercise, muscle growth

Was Popeye Right?

Author: Dr. Stephen Chaney

can eat spinach for muscle growthYou may have seen the recent headlines proclaiming that eating spinach will make you stronger. The more “mature” adults among my readers may remember the Popeye cartoons of our youth. Every time Popeye was on the brink of disaster he would down a can of spinach and become superhuman. Was Popeye right? Can spinach actually improve strength and endurance?  Can you eat spinach for muscle growth?  To answer those questions, I analyzed the study behind the headlines.

The short answer is that there may be some truth to the headlines, but you would never be able to prove it from the study they quoted.

Even worse, this study and the headlines it generated are typical of the sports nutrition marketplace. There are far too many headlines and sports nutrition products based on weak and inconclusive studies.

Spinach for Muscle Growth?

spinachLet’s start at the beginning. In the first place the study behind the headlines (De Smet et al., Frontiers In Physiology, 7: 233-244, 2016) did not actually use spinach. In fact, participants were advised to avoid nitrate-rich foods like spinach and beets during the study.

The study enrolled moderately-trained male students from the University of Leuven in Belgium. All the participants completed 5 weeks of sprint interval training (SIT) consisting of 30 second sprints followed by 4.5-minute recovery intervals on an exercise cycle. This was repeated 4-6 times per session 3 times per week.

One group took a sodium nitrate supplement containing 400 mg of nitrate 30 minutes before each workout. The other group received a placebo. There were only 9 students in each group. [I have simplified the study design for the purposes of this discussion. There were other aspects of the study, but they are not relevant to our discussion.]

The investigators measured maximum oxygen consumption (a measure of exercise efficiency and endurance), maximum power output during a 30-second sprint, and composition of quadriceps muscle fibers both before the 5-week training started and again when it was completed.

The results were disappointing:

  • thumbs downNitrate supplementation caused a modest increase in fast twitch (type IIa) muscle fibers compared to placebo. That is a physiological response that may (or may not, depending on who you believe) allow high intensity exercise to be sustained for longer without fatigue.
  • Nitrate supplementation failed to show any significant benefit for any other measure of exercise capacity. In particular, no effect of nitrate supplementation was observed on:
    • Maximum oxygen consumption
    • Maximum power output
    • Peak heart rate
    • Time to exhaustion.
    • Various metabolic markers of exercise efficiency

In spite of these largely negative results, the authors concluded: “The current experiment demonstrated that oral nitrate supplementation during short-term sprint-interval training increased the proportion of type IIa muscle fibers, which may contribute to enhanced performance in short maximal exercise events…”

“May” is the operative word here. Their data did not provide any evidence that nitrate supplementation actually improved performance.

Online headlines (the kind of nutrition information most people read) took it a step further. For example, one headline claimed “Spinach Can Boost Your Physical Fitness and Muscle Strength.” That headline came out of thin air.

Sports Nutrition Myths

mythsUnfortunately, this study is typical of many of the sports nutrition studies I have reviewed over the years. Most of them are very small studies. In many of them only one or two measure exercise performance change, while other measures show no effect of supplementation.

That doesn’t stop bloggers from hyping the studies and creating sports nutrition myths. It also doesn’t stop companies from offering sports products with those ingredients and making outrageous claims about how their product will make you bigger, faster, and stronger.  For example, a claim that you can eat spinach for muscle growth.

It is only when dozens of studies have been published, and a meta-analysis combines the data from all the studies that we are in a position to see whether any particular nutrient has a statistically significant effect on performance.

Must You Eat Spinach for Muscle Growth or Could Nitrates Provide Exercise Benefits?

nitrates and exerciseDespite the weakness of this particular study, there is reason to believe that nitrates might improve exercise performance.

  • There is a plausible mechanism. In the body nitrates are converted to nitric oxide, which improves arterial health, lowers blood pressure, and enhances blood flow. Increased blood flow to the muscles could enhance exercise efficiency.
  • Other studies have come to a similar conclusion. There are several other exercise studies Health Benefits of Beetroot Juice involving supplements containing either nitrates or beetroot juice (which is rich in nitrates) that have suggested that supplementation improves exercise efficiency. Each of the studies are small and inconclusive by themselves, but in the aggregate they suggest that nitrate may have some benefits.
  • Arginine, which also enhances nitric oxide production, is well established in the sports nutrition world. There are dozens of published exercise studies involving arginine and meta-analyses of these studies suggest that arginine provides modest benefits. However, there is an important caveat, which I shall explain below.

In short, the idea that nitrate supplementation might improve exercise performance is plausible. However, plausible is a long way from proven.

The Ultimate Irony

When you analyze the meta-analyses of arginine supplementation and exercise performance studies, the ultimate irony is that arginine supplementation is most effective for untrained individuals who are just beginning an exercise program. It provides little benefit for trained athletes (R. Bescos et al, Sports Medicine, 42: 99‐117,2012).

There is a logical explanation for this observation. Intense exercise also enhances nitric oxide production and blood flow to the muscle. Most highly trained athletes have already maxed their nitric oxide levels and have excellent blood flow to their muscles. Arginine (or nitrate) supplementation provides little additional benefit for them.

Why do I call this the ultimate irony? Think about it for a minute.

The people most likely to use sports supplements with arginine or nitrate are gym rats and highly trained athletes – the people who get the least benefit from those supplements.

The people least likely to use special sports supplements with arginine or nitrate are the weekend warriors and the busy professionals who are just trying to stay fit – the people who are most likely to benefit from those supplements.

 

The Bottom Line

 

  • Recent headlines have suggested that you can eat spinach for muscle growth and exercise performance.
  • When you look at the study behind the headlines, the study was done with nitrate, not with spinach. Spinach is a nitrate-rich food (as are beet roots), but the headlines were clearly misleading.
  • The study was also inconclusive. It was a small study, and most parameters of exercise performance were not affected by nitrate supplementation.
  • Unfortunately, this kind of small, inconclusive study is all too common in the sports nutrition literature. That doesn’t stop bloggers from hyping the studies and creating sports nutrition myths. It also doesn’t stop companies from offering sports nutrition products with those ingredients and making outrageous claims about how their product will make you bigger, faster, and stronger.
  • However, other studies suggest the idea that nitrate in food or supplements could improve exercise performance is plausible.
  • In our bodies, nitrate is converted to nitric oxide, which enhances blood flow to the muscles.
  • Other studies with nitrate and with beetroot juice (an excellent source of nitrate) have shown some exercise benefits.
  • Arginine, which is also converted to nitric oxide, is a fairly well established sports supplement.

Of course, plausible is a long way from proven.

  • The ultimate irony is that the people most likely to use sports supplements with arginine or nitrates are gym rats and highly trained athletes. They already have excellent blood flow to their muscles. They are the people who get the least benefit from those supplements.
  • In contrast, the people least likely to use special sports supplements with arginine or nitrates are the weekend warriors and the busy professionals who are just trying to stay fit. Those are the people who are most likely to benefit from those supplements.

 

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure or prevent any disease.

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One of the Little known Causes of Headaches

Posted August 15, 2017 by Dr. Steve Chaney

Your Sleeping Position May Be Causing Your Headaches!

Author: Julie Donnelly, LMT – The Pain Relief Expert

Editor: Dr. Steve Chaney

 

Can sleeping position be one of the causes of headaches?  

A Sleeping position that has your head tilted puts pressure on your spinal cord and will cause headaches. I’ve seen it happen hundreds of times, and the reasoning is so logical it’s easy to understand.

causes of headachesYour spinal cord runs from your brain, through each of your vertebrae, down your arms and legs. Nerves pass out of the vertebrae and go to every cell in your body, including each of your organs. When you are sleeping it is important to keep your head, neck, and spine in a horizontal plane so you aren’t straining the muscles that insert into your vertebrae.

The graphic above is a close-up of your skull and the cervical (neck) vertebrae. Your nerves are shown in yellow, and your artery is shown in red.  Consider what happens if you hold your head to one side for hours. You can notice that the nerves and artery will likely be press upon. Also, since your spinal cord comes down the inside of the vertebrae, it will also be impinged.

In 2004 the Archives of Internal Medicine published an article stating that 1 out of 13 people have morning headaches. It’s interesting to note that the article never mentions the spinal cord being impinged by the vertebrae. That’s a major oversight!

Muscles merge into tendons, and the tendons insert into the bone.  As you stayed in the tilted position for hours, the muscles actually shortened to the new length.  Then you try to turn over, but the short muscles are holding your cervical vertebrae tightly, and they can’t lengthen.

The weight of your head pulls on the vertebrae, putting even more pressure on your spinal cord and nerves.  Plus, the tight muscles are pulling on the bones, causing pain on the bone.

Your Pillow is Involved in Your Sleeping Position and the Causes of  Headaches

sleep left side

The analogy I always use is; just as pulling your hair hurts your scalp, the muscle pulling on the tendons hurts the bone where it inserts.  In this case it is your neck muscles putting a strain on your cervical bones.  For example, if you sleep on your left side and your pillow is too thick, your head will be tilted up toward the ceiling. This position tightens the muscles on the right side of your neck.

sleeping in car and desk

Dozing off while sitting in a car waiting for someone to arrive, or while working for hours at your desk can also horizontal line sleepcause headaches. The pictures above show a strain on the neck when you fall asleep without any support on your neck. Both of these people will wake up with a headache, and with stiffness in their neck.

The best sleeping position to prevent headaches is to have your pillow adjusted so your head, neck, and spine are in a horizontal line. Play with your pillows, putting two thin pillows into one case if necessary. If your pillow is too thick try to open up a corner and pull out some of the stuffing.

 

sleeping on stomachSleeping on Your Back & Stomach

If you sleep on your back and have your head on the mattress, your spine is straight. All you need is a little neck pillow for support, and a pillow under your knees.

Stomach sleeping is the worst sleeping position for not only headaches, but so many other aches and pains. It’s a tough habit to break, but it can be done. This sleeping position deserves its own blog, which I will do in the future.

 

Treating the Muscles That Cause Headaches

sleeping position causes of headachesAll of the muscles that originate or insert into your cervical vertebrae, and many that insert into your shoulder and upper back, need to be treated.  The treatments are all taught in Treat Yourself to Pain Free Living, in the neck and shoulder chapters.  Here is one treatment that will help you get relief.

Take either a tennis ball or the Perfect Ball (which really is Perfect because it has a solid center and soft outside) and press into your shoulder as shown.  You are treating a muscle called Levator Scapulae which pulls your cervical vertebrae out of alignment when it is tight.

Hold the press for about 30 seconds, release, and then press again.

Your pillow is a key to neck pain and headaches caused by your sleeping position.  It’s worth the time and energy to investigate how you sleep and correct your pillow.  I believe this blog will help you find the solution and will insure you have restful sleep each night.

Wishing you well,

Julie Donnelly

 

About The Author

julie donnelly

Julie Donnelly is a Deep Muscle Massage Therapist with 20 years of experience specializing in the treatment of chronic joint pain and sports injuries. She has worked extensively with elite athletes and patients who have been unsuccessful at finding relief through the more conventional therapies.

She has been widely published, both on – and off – line, in magazines, newsletters, and newspapers around the country. She is also often chosen to speak at national conventions, medical schools, and health facilities nationwide.

These statements have not been evaluated by the Food and Drug Administration. This information is not intended to diagnose, treat, cure or prevent any disease.

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