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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Shermer’s Neck Pain Relief

Posted January 16, 2018 by Dr. Steve Chaney

Shermer’s Neck Is An Ultra-Cyclist’s Nightmare

Author: Julie Donnelly, LMT – The Pain Relief Expert

Editor: Dr. Steve Chaney

shermer's neck pain ultracyclistShermer’s Neck is a condition where the muscles of the back of your neck become so tight that they lose the ability to hold your head up. It is a condition most frequently associated with ultracycling.

Do you love to cycle?  Perhaps you’re an ultracyclist and ride for many hours every week.  If you are, you may already know about Shermer’s Neck.

As you are well-aware, an ultracyclist leans forwardThis is called the “aerodynamic position.” When you do that, you are slicing through the wind, and you aren’t losing speed when the wind hits your chest. However, you need to hold your head up to see where you are going and maintain that position for several hours. That is what causes Shermer’s Neck.

Shermer’s Neck And The Non-Athlete

shermer's neck pain painterYou don’t have to be an ultracyclist to suffer from Shermer’s Neck. Do you do anything that has you look up for hours, such as being a house painter? Even something as simple as having your computer screen too high can force you to have your head tilted up for long periods of time while working.

If so, Shermer’s Neck can still affect you, and seriously impact your life. Fortunately, non-athletes don’t usually have as severe a problem as the ultracyclists.

Why Does Looking Up Cause Shermer’s Neck?

shermer's neck painYour posterior neck muscles primarily originate at the middle of your back, along your spine. They go up your back and neck, and insert into either your cervical spine, or the bottom of your skull. When these muscles contract, they pull your head back.  When the muscles of the posterior neck contract, if you are standing, you’ll be looking at the ceiling. If you’re a cyclist, your posterior neck muscles contract in order for you to look forward.

How To Treat The Muscles That Cause Shermer’s Neck

shermer's neck pain pinchThe primary muscles that cause Shermer’s Neck are:

To treat the muscles that cause a repetitive strain injury in your neck, tilt your head back and pinch the muscle that is right next to your spine.

shermer's neck pain reliefNext, press the three middle fingers of your opposite hand deeply into the muscle fibers, going from the base of your scalp to as far as you can reach down the center of your back, right alongside your spinal column.

While pressing deeply, slowly lower your chin toward your chest so you are stretching the muscle fibers.  Don’t let your hand slide on your neck or you will miss the stretch.

Do both self-treatments on both sides of your neck.

shermer's neck pain relief bookYou can find the full treatments for your entire neck and upper back by going to my book, Treat Yourself to Pain-Free Living . This book has treatments for your entire body, from your head to your feet.  YOU are your own Best Therapist!  Stop pain quickly and easily with self-treatments you can do anytime, anyplace.  Get relief from Shermer’s Neck pain by following the steps above.

Wishing you well,

Julie Donnelly

 

About The Author

julie donnellyJulie 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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