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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Latest Article

Relieve Hip Pain After Sitting or Driving

Posted June 20, 2017 by Dr. Steve Chaney

Relief is Just a Few Movements Away!

Author: Julie Donnelly, LMT – The Pain Relief Expert

Editor: Dr. Steve Chaney

 

relieve hip pain after sittingI’m on a long business trip, speaking and teaching in Tennessee and New York, and the drive from Sarasota, FL meant many hours of driving over several days.  One of my stops was to visit with Suzanne and Dr. Steve Chaney at their home in North Carolina.  It was that long drive that became the inspiration for this blog.

After all those hours of driving, my hip was really sore. It was painful to stand up. While talking to Suzanne and Dr. Chaney I was using my elbow to work on the sore area, and when we were discussing the blog for this month it only made sense to share this technique with you.  So, Dr. Chaney took pictures and I sat at his computer to write.  I thought others may want to how to relieve hip pain after sitting or driving for long periods.

What Causes Anterior Hip Pain?

As I’ve mentioned in posts in the past, sitting is the #1 cause of low back pain, and it also causes anterior hip pain (pain localized towards the front of the hip) because the muscles (psoas and iliacus) pass through the hip and insert into the tendons that then insert into the top of the thigh bone.  When hip pain reliefyou try to stand up, the tight muscle tendons will pull on your thigh bone.  The other thing that happens is the point where the muscle merges into the tendon will be very tight and tender to touch. You aren’t having pain at your hip or thigh bone, but at the muscular point where the muscle and tendon merge.

It’s a bit confusing to describe, but you’ll find it if you sit down and put your fingers onto the tip of your pelvis, then just slide your fingers down toward your thigh and out about 2”. The point is right along the crease where your leg meets your trunk.

The muscle you are treating is the Rectus Femoris, where it merges from the tendon into the muscle fibers.  Follow this link, thigh muscle, to see the muscle and it will be a bit easier to visualize.

You need to be pressing deeply into the muscle, like you’re trying to press the bone and the muscle just happens to be in the way.  Move your fingers around a bit and you’ll find it.

Easy Treatment for Anterior Hip Pain After Sitting

relieve hip painHere is an easy treatment for hip pain after sitting you can administer yourself.  First, sit as I am, with your leg out and slightly turned.

Find the tender point with your fingers and then put your elbow into it as shown.

It’s important to have your arm opened so the point of your elbow is on top of the spasm.  It’s a bit tricky, but if you move about a bit you’ll come on to it, and it will hurt.  Keep the pressure so it’s tolerable, not excruciating.

After you have worked on this point for a few minutes you can move to the second part of the treatment.

hip pain treatmentPut the heel of your “same-side” hand onto your thigh as close to the spasm as you can get.  Lift up your fingers so the pressure is only on the heel of your hand.  You can use your opposite hand to help give more pressure.

Press down hard and deeply slide down the muscle, going toward your knee.  You can also kneed it like you would kneed bread dough, really forcing the muscle fibers to relax.

I’m putting in a picture from a previous blog to explain how you can also treat this point of your rectus femoris by using a ball on the floor.

As shown in this picture, lie on the floor with the ball on your hip muscle, and then slightly turn your body toward the floor so the ball rolls toward the front of your body. You may need to move the ball down an inch or so to get to your Rectus Femoris.

When you feel the pain, you’re on the muscle.  Just stay there for a minute or so, and if you want you can move so the ball goes along the muscle fibers all the way to your knee.

pain free living book coverIt may be a challenge to find this point, but it’s well-worth the effort!

In my book, Treat Yourself to Pain Free Living, I teach how to treat all the muscles that cause pain from your head to your feet.

Wishing you well,

Julie Donnelly

julie donnelly

About The Author

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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