About jonathan.thompson

Jonathan Thompson is a Certified Personal Trainer and Running Coach with the American Council on Exercise, specializing in nutrition. In addition to his real-world experience working with clients, his articles and blogs on fitness advice have been published on many websites and magazines.

Rethinking U.S. Dietary Guidelines

For a while now, many different organizations and independent health experts have been pushing for a shift in the U.S. dietary guidelines. And for good reason: Obesity and all of it’s associated conditions – including heart disease and diabetes – are still steadily increasing despite all sorts of health initiatives. In fact, according to the CDC, obesity rates in American doubled for adults and tripled for children between 1980 and 2008. Those dates are particularly fascinating because it was during the 1980s that we really saw a push to adopt a low fat dietary approach. Obviously, something needs to change.

Beyond statistical evidence, though, there is an ever-growing collection of scientific information that runs counter to everything we thought we knew about nutrition. One particularly fascinating editorial, published in 2014 in the journal Open Heart focused it’s attention on the 1977 dietary guidelines. It was in that year that Americans were told to decrease their intake of saturated fats and cholesterol while increasing their daily allotment of carbohydrates. The author, Dr James DiNicolantonio, points out that those initial recommendations were based on the incredibly flawed findings of the Seven Countries Study – the authors of which had access to information from 22 countries but chose to only use the data from seven. Later review of the complete information contradicted the recommendations, but was largely ignored since the damage had been done.

The current evidence actually suggests exactly the opposite: That saturated fat does not increase your risk of heart disease but refined carbohydrates do.

Building on this idea, DiNicolantonio worked with a team of researchers to publish a study in a more recent edition of Open Heart that looked more carefully at the historical research that took place before the low-fat craze really got started.



Looking Back

To further build the case against the above-mentioned dietary guidelines, the team went back and performed a meta-analysis of six studies including information from 2467 adult men. The studies used were all took place before 1983 and focused on the relationship between dietary saturated fat, cholesterol and the development of heart disease.

In all of the studies, a reduced-fat diet was not shown to reduce mortality rates any more than the control groups. Basically, decreasing saturated fat intake did very little for the health of the subjects in these studies.

And yet, the recommendations were made anyway.

The team concluded that the available research leading up to the release of the dietary guidelines “did not support the introduction of dietary fat recommendations in order to reduce” the risk of heart disease. They even went so far as to say “Dietary advice not merely needs review; it should not have been introduced.”


A Word of Caution

So, as we learn more and more it seems like the dietary guidelines we were all raised with are not only wrong but potentially dangerous. It should be plainly stated, though, that that does not mean that saturated fat is not without it’s dangers.

First, obesity and heart disease are complex conditions and should not even be blamed on one factor. The increased knowledge of epigentics have even lead some experts to suggest that the culture of the 1950s – which included plenty of tobacco and alcohol, while encouraging women to gain very little weight during pregnancy – may still be effecting our genetic expression.

Second, dietary fat is very calorie-dense. While it may not be as bad for your heart as we once thought, in excess it is most certainly not great for your waistline if its leading you into caloric excess.









The Controversy Over Herbal Supplements

Herbal supplements are a massive industry. In 2013, a Canadian study reported 65,000 different dietary supplements on the market with about 150 million regular consumers. That means that nearly half of the American people routinely invest in supplements, accounting for $6 billion spent on the products in 2013.

All of this is done based on a certain degree of trust – confidence that those bottles contain exactly what the label says. Unfortunately, this is not always the case.

Truthfully, though, “tainted” supplements are really nothing new. For those who watch the industry, it’s not uncommon for the FDA to find prescription drugs in “herbal” products or to learn that those supplements contain close-to-none of the key ingredient.

But when this happens in major retailers like Target, GNC, Walmart and Walgreens – places many people are likely to purchase supplements – it’s going to make big news. And that’s exactly what happened last week when researchers at Clarkson University in Potsdam, New York tested herbal products from these national chains.

Their findings were startling and upsetting to many. However, the research is not without its critics, including a few unexpected organizations. To get a clear picture of the issue, then, we need to look at both sides of the controversy.


The Initial Research

At the request of New York Attorney General Eric Schneiderman, researchers collected multiple bottles of six different herbal supplements from Target, GNC, Walmart and Walgreens. The specific products that they looked at included St. John’s Wort, ginseng, echinacea, ginkgo biloba, garlic and saw palmetto – focusing on the store-brand of each.

The supplements were then put through DNA testing to determine whether or not they contained what the label claimed, in the amounts that were listed. A frightening amount of supplements failed miserably, not only lacking the key ingredient but containing substances that were not listed. A few products – including Spring Valley St. John’s Wort and Herbal Plus Ginseng – were nothing but cheap fillers like beans, rice, wheat, garlic and even ground-up houseplants.

Understandably, there as been a massive and fast public outrage over the findings. Not only is this complete fraud, but it could also be a serious danger to people with food allergies.

For the most part, the stores have responded well to the findings – only Target has refused to comment until they are able to review the research.


The Other Side

Many organizations, though, have criticized the DNA testing used in the trials as unreliable, “bad” science. Primarily, this is because the DNA of plants can be damaged or altogether removed during processing. And DNA testing won’t find extracts of a specific herb if that was used instead of the actual portions of the plant.

What’s interesting is that we would naturally expect trade organizations to be critical of the research – and they have been, even launching their own studies. But when independent watchdog groups that test and review supplements have negative things to say about the science, it is truly surprising.

Perhaps the biggest shock is that the director of US Pharmacopeia (USP), a group that sets quality standards and testing protocols for drugs, vitamins and supplements, joined the critics – stating that DNA testing is a useful scientific tool but that it has its limits.

Another independent testing lab, ConsumerLab.com, told CBS News that the use of DNA testing was inappropriate in this application.


The Bottom Line For You

There is definitely something wrong with the supplement industry, which is largely unregulated by the Federal government, and this study gives further proof that the industry is in need of reform. But the science behind it is undoubtedly faulty and should be backed up by more reliable testing techniques. These techniques are out there and should have been used in the first place.

To protect yourself, then, do your own research. If you do decide to continue to invest in supplements, look for a USP or similar stamp which shows that they product has been independently tested.






Do Foam Rollers Help Runners?

It might not seem like it, but the warmer days of spring are quickly approaching and – with them – the start of training season. We’ve talked a lot in past posts about managing and reducing the amount of pain that athletes deal with during training and now we’re going to cover a technique that has been rapidly gaining popularity over the last few years: foam rolling.

Proponents of foam rolling – more clinically called self-myofascial release – claim that it can reduce soreness after a workout as well as improve athletic performance. So, do foam rollers really help runners and other athletes?


What Exactly Is It?

First, though, let’s make sure that we’re clear about what foam rolling is. Fortunately, it’s pretty straightforward; Foam rolling involves rolling a foam cylinder over various parts of your body. The idea is to use the pressure of your body weight against the roller to work out any knots in the muscles or connective tissue that surrounds them (fascia). In theory, this could increase flexibility and help to prepare your muscles for activity.

But, doesn’t static stretching do that? To an extent, yes. The issue with static stretching before a workout, when your muscles are cold, is that it can actually reduce your strength and power once the activity begins. Exercise physiologist Mike Ross from the Gottlieb Center for Fitness compares the muscles to shoe laces with a knot in them. If you pull on the laces – stretching – the knot will only get tighter. Foam rolling, however, allows you to kneed the knots out of your muscles.


Does It Work?

On paper, this makes sense. But how does it hold up in practice?

First, we’ll focus on the claims of reduced pain and soreness. It seems, at least in early studies, that there’s some promise here. A 2014 study published in the journal Medicine and Science in Sports and Exercise found that foam rolling did successfully relieve pain and soreness when performed at the end of a workout. Interestingly, this study also reported that the subjects performed better on subsequent workouts.

Does this mean, then, that foam rolling can help improve athletic performance? Probably not. Another study published around the same time in the Journal of Strength and Conditioning Research switched things up and had participants foam roll before their workouts. There was no effect – positive or negative – on their workout performance. However, this study did find that the subjects experienced less fatigue after foam rolling.

Taking the two studies together, it seems like foam rolling can increase recovery rates and help you make more significant improvements during workouts. While it might be disappointing that foam rolling has no immediate performance-enhancing benefits, remember that static stretching decreases performance. Through that lens, foam rolling has a clear advantage.

A third study confirmed that foam rolling does not decrease performance while also showing that the practice can increase range-of-motion.


The Bottom Line

Foam rolling, then, has some pretty sturdy science behind it. A few minutes before and after your workouts can help to speed up recovery times while simultaneously decreasing pain and fatigue. In a future post, we’ll cover specific foam rolling exercises that you can incorporate into your routine.









Beet Juice: How does it work?

We’ve written in the past about some of the exciting studies surrounding a pretty unexciting product: beet juice. Several sources have found that a shot of the nitrate-reach beet juice could possible improve endurance and power in athletes when taken a few hours before a workout. And, thrilled by the idea of a legal, non-stimulant, completely healthy performance enhancer, many athletes from various sports have stocked up on beet juice shots.

Beyond athletes, though, some patients with high blood pressure have started asking their doctors if they should start taking beet juice as well. All of this hype is based on the theory that beet juice works by expanding your blood vessels, thereby decreasing blood pressure and increasing the amount of nutrients that can reach your muscles – fueling them for more activity.

A new study from Penn State University, though, questions this theory.


Not What We Thought

First off, let’s be clear: This study was not designed to test the performance-enhancing benefits that have been reported from beet juice. Instead, the researchers were trying to investigate the exact mechanism that causes those benefits. As mentioned above, it was previously thought that the high concentration of nitrates in beets led to an increase in nitric oxide – a vasodilating gas that has become a popular preworkout supplement over the past few years.

In this study, however, the team measured the amount of blood that flowed through the brachial artery in the forearms of their subjects during grip exercises. Surprisingly, there was no change in the the width of the artery when the subjects were given beet juice.

The researchers were careful to note, though, that this lack of dilation was not caused by a lack of absorption. Basically, this means that the nitrates in beet juice do get absorbed and do get converted into nitric oxide. But, for whatever reason, it does not result in the vasodilation that everyone expected.

Interestingly, the beet juice did result in a beneficial softening of the arteries which can result the risk of cardiovascular disease.

The researchers did note that the results of this study were limited by the test group. The subjects use here were young and healthy, with very healthy cardiovascular systems. This shows that beet juice likely does not act as a vasodilator in athletes. However, the study did not look at older individuals, or those with per-existing cardiovascular conditions, so more research is necessary to see if the juice could be useful in a clinical setting.

Also, the exercise intensities used in the study were limited. It is possible that higher intensity activities would have gotten different results.


In Application

So this study does not necessarily debunk the use of beet juice as a performance enhancer but it does show that the juice probably does not work the way everyone thinks. Remember, the study did not even look at athletic performance.

If you have taken beet juice in the past and benefited from it, you aren’t doing yourself any harm. The juice is a rich source of micronutrients that can surely improve various facets of your health.








Caffeine for the Athlete

In several past posts, we’ve discussed the use of caffeine when it comes to athletic performance. For the most part, though, we’ve only looked at general information. Thanks to some newer research that has emerged since those posts were typed, we can now get a little specific. Primarily, we want to look at appropriate dosages of caffeine for and how you can properly manage your caffeine intake for optimum results – and limited side effects.


The Goldilocks Effect

Let’s just get this out there: Caffeine is a drug. As with most drugs, your body will eventually form both a tolerance to – and dependance on – caffeine. Thanks to the dependance, you will crave caffeine and experience withdrawal symptoms when you go without it. But your brain’s ability to form a tolerance means that you will consistently need more and more caffeine to feel the same effects.

For many people, this is knowledge enough to make them totally cut caffeine out of their lives. But the truth is that numerous studies have proven that caffeine can be incredible useful to athletes competing in an number of sports. The stimulant has been shown to improve power output, endurance, mental focus, reaction time and the metabolism of fats. The trick, then, is to find a maintenance dose of caffeine that will allow you to enjoy the benefits without developing a tolerance and dependance.

Since caffeine effects people differently, depending on a variety of factors, it’s difficult to come up with an exact dosage. According to many experts, though, dependance is unlikely to occur when your daily dose hovers around 100mg of caffeine every day – equivalent to about one 8oz cup of coffee. Again, though, this may not be true for everyone and some studies have observed withdrawal symptoms after discontinuing even this small dose. It may take some experimenting to find the sweet spot for you – the lowest possible daily dose of caffeine that allows you to feel the benefits without being totally hooked.


The Hardcore Taper

If you’re really willing to dive in and make some serious sacrifices to get your coffee habit under control while discovering your optimum maintenance dose, you might think about a two-week taper. To start, pick a two week period that seems like it will be relatively low in stress and estimate your normal caffeine intake – including coffee, tea, soda, energy drinks and anything else you can think of that contains even small amounts of caffeine.

Each day, gradually decrease the amount of caffeine until you’re down to just 100mg. Maintain this for a few days and then – when you’re ready – cut out all caffeine for three days. You will probably experience headaches and other withdrawal symptoms. After a few days, though, these will fade and you will totally free of your caffeine habit. At this point, you can resume 100mg or less of caffeine every day and you should be able to exercise more control over your habit.


For the Athlete

So far, though, we’ve only covered daily use. Once you find your lowest possible baseline dose, you can start to use caffeine as a performance enhancing supplement. In most studies, the optimum dose is calculated as being ~3-6mg of caffeine for each kg of body weight. Which means you’ll have to do some math. Sorry.

If you’ve found your ideal daily dose and it’s relatively low, you should be able to make due with just 3mg/kg. To keep yourself from developing a tolerance while using caffeine in this way, only boost your dose on training days and only when you feel like you need it. Some days you may be feeling great and not need any help, other days may be different.

Strictly speaking, coffee is not the best source of caffeine. The exact amount of caffeine found in the coffee will depend on a huge number of factors, including brewing method, filter type and the quality of bean. If you really want to be precise, you might consider a caffeine pill or powder that has a specific dosage.







Manage Stress By Accepting It

As athletes, we tend to focus primarily on physical stress – the way that our daily lives and our training affects our bodies. Unfortunately, the tendency is to largely ignore the mental aspect of this equation.

In reality, mental stress can have a huge impact on your health and physical performance. Short bursts of the so-called “stress hormone” cortisol are a natural part of your body’s fight-or-flight response and are intended to suppress certain biological systems that are not absolutely essential in an emergency situation. While this changes everything from your immune system to your reproductive system, the impact of real interest to athletes is what cortisol does to body composition. Just in case you’re going to need it down the road, cortisol tells your brain that it’s time to start creating – and holding on to abdominal fat. At the same time, cortisol triggers a state of catabolism which causes your body to breakdown muscle for fuel. While this happens on a small, nearly undetectable scale nearly every day, when cortisol levels are chronically high – as can happen through extended physical and/or emotional stress – body composition and athletic performance can be severely affected.

Of course, there are tons of different techniques to manage stress out there. A recent study published in the journal Psychoneuroendocrinology looked specifically at something called “dispositional mindfulness” – the ability to be aware of your experiences in an accepting and nonjudgemental way.


The Way You See It

Specifically, the researchers were curious as to why two people can experience the same level of self-rated mental stress and yet have such varying physiological responses to it. For four mornings, the group of 43 female subjects were asked to describe their levels of perceived stress, anxiety and negative feelings. The researchers also asked the women if they were able to accept the negativity without judgement. Perhaps most interestingly, the researchers also monitored the subjects’ cortisol levels within the 45 minutes after waking up.

Once the data was compiled and analyzed, it became clear that the women who were more articulate about their thoughts and emotions had lower cortisol levels then those who had difficulty expressing and accepting their internal experiences.

Of course, this is just a preliminary study – limited by the use of self-reporting and small sample size – but it still proves an interesting point: The key to managing stress is not avoiding negative thoughts altogether. Instead, we have to learn to process these emotions in a healthful way.

A related study out of Brown University also found that dispositional mindfulness can improve your overall health, even reducing markers of cardiovascular disease.


How To Do It

Unfortunately, this is not a skill that comes easily to everyone. Many people find it difficult to simply experience negative thoughts or emotions, rather than fighting them. With practice, though, this habit can be changed through meditation and mindful exercise. Apart of these disciplines, however, there haven’t been a lot of options for people wanting to improve their dispositional mindfulness.

Interestingly, a study published in Mental Health and Physical Activity compared the impact of both relaxation training and aerobic exercise on the mindfulness of 149 men over 12 weeks. Surprisingly, the relaxation group saw no improvements in dispositional mindfulness. The aerobic group, however, did – lending support to the idea of running to clear your head.

Learning to process emotional stress, instead of ignoring or rejecting it, can help to reduce the severity of cortisol spikes and improve your overall health. While there are many ways to do this, sticking to your routine of cardiovascular training could be a big step. Of course, if that isn’t doing it for you, you might try a mindful exercise style like yoga or Pilates.








Study Confirms: Fast Food Is Unhealthy

To be honest, you likely already knew that your favorite fast food haunt wasn’t doing you any dietary favors. It’s no secret that we should all be limiting our frequency at these establishments if we want to keep our weight down and our bodies functioning properly.

But, after a wave of negative press during the late 1990s and early 2000s, many fast food chains seemingly made an effort to improve their image. During that time, a series of documentaries and investigative news features exposed the unsavory – and often unethical – nutritional practices of these establishments, leading to a huge dip in popularity.

The situation didn’t improve for them when governmental agencies began to move against the use of trans fats in fast foods. This particularly unhealthful form of fat was in just about every item on many restaurants menus and a highly publicized overhaul quickly began.

Then, of course, there was a barrage of criticism over the often ridiculous portion sizes offered – some would even say “encouraged” – by these chains. In response, McDonald’s even dropped their trademark Supersize option in 2004 – although, the chain claimed it was only done in an effort to simplify the menu.

So, with their newer, healthier images fast food chains are still a major part of the American diet. The question arises, then, are they actually any better for us after these changes?


The Startling Numbers

In two reports, researchers at Tufts University compared the portion sizes and nutritional make up of three large fast food chains between 1996 and 2013. Specifically, the team looked at the composition of fries, cheeseburgers, grilled chicken sandwiches and regular colas.

Despite all of their efforts to make it seem otherwise, the data is clear: Fast food chains have done little to improve their menus. The one notable exception was the sharp decline in the use of trans fats – but only in fries. For the most part, this was directly related to legislative action taken between 2005 and 2009. Trans fats are still alive and well in many other options, though, including burgers and milkshakes.

Even when trans fats did slowly make an exit, however, the food as a whole didn’t really improve all that much. The total calories and sodium content remained remarkably high. Depending on the restaurant, a single cheeseburger could supply you with as much as 63 percent of your recommended daily sodium intake. Add fries to that and you’re up to 91 percent of your allowed sodium for the day.

Of course, it’s not completely surprising that fast food is still unhealthy. What is off-putting, though, is how little things have changed and just how unhealthy these restaurants still are. In fact, some chains even feature menu items that cram about 1000 calories into one single sandwich. For the average person, that’s about half the daily allotment. In one sandwich. Drinks are still woefully large, too, and a single beverage intended for one person could contain as much as 800 calories. A complete fast food meal, then, with burger, fries and a drink could run as much as 1750 calories. That means that that one meal could account for about 88 percent of a 2000 calorie per day diet.

Again, this isn’t really news. But the point is that, despite their well-designed marketing campaigns that try to argue otherwise, fast food restaurants have not really changed their menus.









Tips to Keep Your New Year’s Resolution

Well, here we go again. New Year’s. The topic of resolutions is flooding websites, talk shows and magazines right now, with everyone discussing what they want to change and how they’re going to do it. But, as you’ve doubtlessly read in myriad pessimistic articles, the vast majority of resolutions fail. In fact, the official statistics claim that only 8 percent of people actually follow through on their resolutions. And, since most resolutions have to do with health and fitness, this is of particular interest to us. What follows, then, are some basic tips you can use to keep your New Year’s Resolution.

1. Set Good Goals –

The primary downfall of resolutions is that are simply not well-planned goals. As we’ve discussed in previous posts, the American Council on Exercise likes the S.M.A.R.T acronym for proper goal design. This means that good goals must be specific, measurable, attainable, relevant and time-bound.

So, simply saying “I’m going to lose weight,” doesn’t pass the test. While it is absolutely measurable and attainable, none of the other criteria is satisfied. A much better goal would be “I’m going to lose 5 pounds in a month.” This meets all the requirements to be a SMART goal.

2. Get Quality Advice –

The is an incredible amount of just plain bad advice available to you. It’s everywhere. For example, last week we covered a recent study that exposed the startling amount of false information being spread by means of popular and trusted medical TV talk shows. Often, it’s well-meant. But, perhaps just as often, it’s intended to sell you something. Either way, it’s important to be picky when deciding who to listen to. Not only could following faulty advice impede your progress, it could even serious harm to your health.

If you decide to work with a trainer, don’t be afraid to ask about their credentials since it’s very common for people to work as personal trainers with no education or certification in the field. When it comes to diet advice, though, even more caution is necessary. Everyone has an opinion on what constitutes a “healthy” diet and what works for them may not work for you. For accurate personalized dietary advice, seek out a registered dietician.

Whether its a trainer or a dietician, having a trained professional on your side can be a huge motivation for you to stick to keep your New Year’s Resolution – especially if you’re paying them.


3. Think Long-Term –

Another issue, closely related to the SMART requirements discussed earlier, is that many New Year’s Resolutions are last minute, emotional decisions. There’s no planning behind them, nothing to support them and no real, lasting neurological connection to them. And, while that last bit might sound a little ridiculous, consider this: Healthy eating and exercise are habits. Behind the scenes, habits are nothing but reinforced thinking patterns that form new neural pathways. After about 18 to 21 days of repeating a behavior, these new patterns become hardwired into your brain and form habits.

Keeping your resolution, then, is a matter of sticking to it for close to a month and retraining the way that your brain functions. This requires discipline and planning.







How Accurate Are Medical Talk Shows?

It’s pretty common that I get asked various health and fitness questions – and this is likely true of most fitness professionals – that begin with the words “Doctor Oz says…” or “I saw on the Doctors…” And, most of the time, this puts me in an awkward situation because I usually disagree with the advice being dispensed on medical talk shows. But, since I don’t regularly watch those shows and definitely don’t research each and every claim they make, I’m not exactly fair or unbiased.

A new review published in the British Medical Journal, however, took the time to do exactly that. For the article, a team of researchers randomly selected 40 episodes of The Dr Oz Show and 40 episodes of The Doctors. Every recommendation from each episode was then isolated. Of the resulting pool of recommendations, 80 were then randomly selected from each show. The team then went to work evaluating the research on each of those 160 recommendations to conclude whether the science supported the claims, contradicted them or was simply non-existent.


The Results

Taken as one large sample, the talk shows did not stand up well under scientific scrutiny. Of all 160 recommendations made on the two shows combined, only 54 percent of those claims actually had science to support them. But the paper also looked at each show individually.

For The Dr Oz Show, the evidence supported about 46 percent of his recommendations, contradicted 15 percent and simply did not exist for the final 39 percent. The paper also reports that Dr. Oz makes about 12 recommendations per episode on average. Lower quality evidence, termed either “believable or somewhat believable,” was found for 33 percent of the claims made by Dr. Oz.

The Doctors had slightly better results – but it was a very small advantage. A total of 63 percent of their recommendations had solid scientific backing, 14 percent were opposed by the research and the remaining 24 percent had no related studies to be found. However, 53 percent of the Doctors’ recommendations could be tied to believable or somewhat believable evidence.

It’s also worth noting that any potential conflicts of interest were disclosed only .4 percent of the time, between both shows.


 The Take-Away

Clearly, then, medical talk shows don’t seem to fair well when placed under scientific analysis. Although a 15 percent error rate might not seem like much, think about it this way: That equates to 12 incorrect recommendations made in every 80 – the sample size. On average, Doctor Oz makes 12 recommendations each episode. This means that, statistically speaking, one entire episode of The Doctor Oz Show could be incorrect.

The numbers work out about the same for The Doctors, as well.

Of course, there’s still the fact that over half of the information provided on these two medical talk shows is correct; It’s not all bad. But the paper rightly concludes by saying, “The public should be skeptical about recommendations made on medical talk shows.”

Instead of taking the recommendations presented on medical talk shows as absolute truth, then, allow it to be your starting point. If you hear something that piques your interest, do your own research.







Shortness of Breath After A Workout

Vitamin C has been a star player on the natural remedy scene for a long time now. The humble vitamin, found in many otherwise healthy fruits and vegetables, has been touted to cure just about everything from cancer to nail-biting. Unfortunately, many of these claims just don’t hold up under the lens of scientific study.

A recent review of the available research, however, suggests that vitamin C might just be the answer to a frustratingly common problem among athletes and casual exercisers alike: Shortness of breath.

Post-exercise Shortness of Breath

Specifically, what the researchers were looking at is called exercise-induced bronchoconstriction (EIB). As the name suggests, this refers to the cluster of respiratory problems that happen after strenuous exercise and are caused by a narrowing of the airways. Typically, this manifests itself as a cough, sore throat and – of course – difficulty taking deep breaths.

Most commonly, EIB is an issue for asthmatics but many endurance athletes struggle with it as well – regardless of whether or not they have asthma.

For the purposes of the review in question, nine randomized trials were analyzed and all of them had positive results. Looked at together, the studies found that vitamin C supplementation – in fairly small doses that we’ll discuss later – halved the duration and frequency of EIB in both trained and untrained individuals.

Obviously, these findings are pretty encouraging for those of us who deal with asthma or other respiratory problems associated with exercise.


Putting It Into Practice

So, if you fall into the group of people who deal with EIB, should you start taking vitamin C. And how much?

Much more research is needed before the experts out there can really pin down any dosage recommendations. That being said, the positive results cited above were all found with doses ranging from .5 to 2g daily. Unfortunately, I could not find any information regarding the timing of the dose – whether the vitamin must be taken within a certain time-frame of the workout or can be taken at any point during the day.

It’s also true that you could be suffering with respiratory problems not associated with EIB. If that’s the case, you may see no relief at all from vitamin C supplementation. Here’s the good news, though: Vitamin C is cheap and has a fairly short list of risks associated with it. Especially when compared to other supplements. Because of that, you may want to experiment to see if a little extra vitamin C could help you deal with shortness of breath after a workout.