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I’ve been following (and often participating in) fitness trends for decades. From Jim Fixx’s outdoor running to Jane Fonda’s work out videos, to Conan-the-Barbarian body building, to step aerobics, to Tae Bo, to hot yoga, to Zumba, and now CrossFit… America’s exercise pendulum has been swinging wildly across the spectrum of possible physical activities. So have we finally reached a balanced mix of strength and cardio for optimum fitness? Maybe.
CrossFit is a system of exercise and nutrition (founded in 2000 by Greg Glassman) that claims to “forge elite fitness.” Their Reebok-sponsored annual games boast that the winners have proven themselves to be “the fittest on earth.” CrossFit advocates a mix of aerobic exercise, gymnastics (body weight exercises), and Olympic weight lifting. Workouts are typically short—30 minutes or less—and intense, requiring maximal physical exertion.
I’ve attended multiple regional Cross Fit competitions, watched national games, competed in a CrossFit style competition, and worked out with several CrossFit athletes as well as attempted their work outs (WOD) on occasion, though I am not a member of a CrossFit gym. All this is to say that I’ve spent a good deal of time contemplating the merits of CrossFit, both as an athlete and as a physician trained in sports medicine. And here’s what I think:
Difficulty. High intensity interval training (HIIT) is an effective and highly efficient way to improve muscle strength and cardio-vascular endurance. In my opinion, CrossFit’s greatest contribution to the fitness industry is its emphasis on HIIT, something that has not been sufficiently emphasized in the past.
Nutrition. CrossFit emphasizes the importance of healthy nutrition as part of its fitness strategy. This is sorely lacking in other systems/regimens. While I might quibble with some of the more extreme “Paleo” proponents within the CrossFit community, there’s no arguing that a diet rich in fruits and vegetables, lean protein, healthy oils, and complex carbohydrates (no sugars or refined flours) is a healthy way to eat.
Community. Peer support encourages consistency in participation. CrossFit does a good job in building community and making everyone feel welcome. All levels of fitness (and all ages) are welcome to join a CrossFit gym and participate to the best of their ability in the workout of the day (WOD).
Affordability. CrossFit gyms are relatively inexpensive to outfit (less high-tech equipment) and are easy to scale. For this reason they provide greater access to people at all income levels, which is a huge plus.
Portability. CrossFitters learn how to use their own body weight to create challenging exercise routines anywhere, anytime. There is no longer any excuse not to get a good workout in, whether you are traveling and can’t get to the gym or you are too busy to break free from the kids to do a more formal work out.
Frequent Injury. CrossFit injury rates are substantially higher than most other fitness regimens. Herniated disks, muscle and tendon ruptures, rhabdomyolysis are not uncommon. In fact, most CrossFit athletes that I know presume that “injury just comes with the territory” and I frequently see Facebook photos of bloody/blistered hands as some kind of badge of honor. I myself sustained a low back injury even when carefully observing my technique during a CrossFit workout, and a dear friend actually ripped off one of the heads of his bicep when attempting an Olympic weight maneuver, while another friend fractured her wrist after falling down during a series of box jumps to exhaustion. Trust me when I say that if you do CrossFit long enough, you’re bound to become injured in some way.
Challenging Technique. Correct exercise form is hard to master, and since many CrossFit moves derive from gymnastics and Olympic weight lifting (sports that take many years to perfect), it is incredibly important to perform movements according to correct mechanical form. Although CrossFit experts strongly agree that good form is the key to safe and effective exercise, the fact is that people don’t always follow directions. In fact, most athletes that I’ve watched at CrossFit gyms suffer from poor form in one or more of their moves – sometimes because of inexperience, and other times because they are too exhausted to perform their final rep(s) correctly and their attention has waned. Functional movement is freer than the usual, controlled weight scenarios in a gym’s circuit training machines. And with that freedom comes the benefit of activating more muscles at a time, but the danger of injury, especially for new initiates or older athletes.
Peer Pressure. The flip side of having a “strong community” that encourages participation, is that the same community may push participants to engage in unsafe exercise practices. I’ve often seen well-meaning CrossFit instructors encourage people to pick up heavier weights than they feel comfortable with in order to push them to become stronger. There is a fine line between healthy encouragement to challenge yourself, and dangerously heavy weight lifting. It’s normal to want to “keep up with the Joneses” to your right and left during a WOD, but when Mr. Jones is a 250 pound tower of muscle, you might not want to be lifting the same weights.
Glorification of the mesomorph. There’s no doubt that committed CrossFitters develop enviably lean, muscular bodies. However, I wince a bit at the tendency for CrossFitters to promote the idea that their way is “THE best way” to be fit, and the bravado surrounding their competitions for “fittest on earth” is exclusionary and unfair. Just because an athlete was born with a different body type, ill-suited to Olympic weight lifting for example, doesn’t mean they can’t be fittest on earth (a rather subjective measure – why not an Ironman as the fittest?) There’s not much variation in the body types of those who are at the top of the CrossFit heap (i.e. large muscle mass, not too short or tall), which speaks to the fact that ultimately this sport is not optimal for all-comers (nor is the position of linebacker on a football team).
My bottom line: CrossFit must be approached with caution, though it provides some excellent HIIT and nutrition principles that can optimize one’s health. If you enjoy strength training (more than cardio or yoga for example) and like camaraderie but can resist the temptation to push yourself into the injury zone, then CrossFit may be for you.
I personally recommend (and participate in) what I would call “CrossFit light” – meaning workouts of similar CrossFit intensity but without extreme weight/maneuvers, and scaling up slowly (especially when new to exercise or a Masters athlete), adding additional cardiovascular training, and eating a diet slightly higher in complex carbohydrates than is generally recommended by strict “paleo” type CrossFitters. And of course, I do not believe that my way is the best or only way to be fit. If you like running, cycling, yoga, Pilates, or even step aerobics – good for you! Aim to be active for an hour/day – and add a little strength training in as you can. If you do that much, you may not be the “fittest on earth” but you’ll be doing more exercise than 96% of Americans!
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This actress keeps her dermatologist on speed dial too.
As a light skinned, be-freckled woman with a history of pre-melanoma, I have been sternly instructed to keep my dermatologist on speed dial. Every six months I dutifully return to his office for inspection – nervously eyeing the biopsy tray as I sweat through my paper gown, legs dangling from a vinyl exam table.
In preparation for my most recent trip, I decided to be “an empowered patient” and arrive with a list of general dermatology and skin care questions that could be answered during my skin check. Judging from the near-syncopal episodes that I induced in my dermatologist while describing some of my hygiene practices, I’m not being very good to my skin. In fact, he wanted me to know that at least three products that I currently use are “of the devil.” Just in case you are inadvertently engaging in demonic skin care practices as I was – I thought I’d share what I learned:
1. Dryer sheets. According to my dermatologist, dryer sheets contain “a horrible chemical that no one can pronounce” that becomes “slathered all over your clothing” during the drying process. Although I was fond of the fresh scent and soft texture of my gym clothes, he assured me that heat and moisture was the best way to re-activate the irritating chemicals on delicate skin, virtually guaranteeing a contact dermatitis of the nether regions. So if you’ve been experiencing any unpleasant post-work out skin “issues” – consider dryer sheets as a potential cause.
2. Antibacterial ointments. Personally, I find that over-the-counter antibacterial ointments do a great job of preventing razor bumps. However, my dermatologist says that repeated or excessive use of these products can lead to allergies and colonization with antibiotic-resistant organisms. So… unless you want to be giving MRSA a “come-hither stare,” you might want to opt out of the Neosporin.
3. Battery-operated exfoliating brushes. I’ve seen so many ads for Clarisonic-type products that I figured they would be a reasonable choice for facial exfoliation needs. In fact, this topic may be somewhat controversial since I know other doctors who recommend these products. However, my dermatologist says that they are overkill and might do more harm than good to delicate facial skin, especially if you use any products that have an exfoliating acid included in their ingredient list, or if you use scrub creams. In other words, if you wash your face regularly, you probably don’t need to use additional aggressive cleaning measures.
In addition to the information provided about evil products commonly used by innocent people across America, my dermatologist offered these general tips for healthy skin:
1. You don’t need so much moisturizer. “You don’t need to put on moisturizer every night just because your mother told you to,” he said, bow tie looming large at eye-level. “Women think they need to apply moisturizer multiple times a day, but there is enough moisturizer in sunscreens and anti-oxidant serums to make additional products unnecessary.”
2. Throw away your 10x mirror. “Honestly, no one sees your skin at 10x, so why should you worry about what it looks like so close up? The best way to make your pores look smaller is to quit looking at them under a magnifier.”
3. Use physical block sunscreen every day. Most of the cheaper, spray-on sunscreens use chemicals to scatter light, but zinc-based sunscreens physically block incoming UV radiation. “The most important part of an ‘anti-aging’ regimen is to avoid sun exposure, and the best way to do that is with constant use of physical blocks.”
4. Skin-lightening cream (hydroquinone) can reduce the appearance of sun damage. Hydroquinone is the active ingredient in most skin-lightening creams. It acts to down-regulate melanin production in melanocytes, but can be reversed fairly easily by UV exposure (i.e. sunlight up-regulates melanin production). So even if you’re already pale-skinned, hydroquinone products can even out skin tones and sun spots – but only if you simultaneously commit to aggressive avoidance of UV exposure.
I hope you’ve found these skin tips enlightening (pun intended). I’ll have to think of some other good questions to ask my dermatologist in 6 months from now, during my next cancer screening. Because as an empowered patient, I intend to learn as much as I can in my 15 minutes with the doctor, and then share it with as many people as possible.
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It is estimated that in seven years from now, half of all Americans will suffer from one or more chronic diseases, a majority of which are weight related. The American Medical Association recently declared that obesity itself is a disease. Obesity advocacy groups say that this move will lead to better health outcomes by providing more treatment options, preventative programs and education, as well as better reimbursement for treating individuals fighting obesity.
But what do patients need to know about weight loss? The good news is that a medically healthy weight does not require a very low percent body fat.
Weight loss for health – not for appearance – comes with a different (and in many cases much less demanding) set of recommendations. So for the purposes of this blog post, I’ll focus on key evidence-based advice for patients at risk for weight related disease…
1. You don’t need to lose that much weight to realize substantial health benefits.
A five to ten percent loss of body weight can lower risk for heart disease and other killers. For obese patients, even a modest weight reduction can have significant health benefits. An eleven pound reduction in weight leads to a fifty-eight percent decrease in the chance of developing diabetes. Even just losing two pounds reduces the risk of diabetes by sixteen percent.
2. Most people who succeed at losing weight (and keeping it off) do so with a combination of diet and exercise.
According to the National Weight Control Registry (NWCR) (a database of more than ten thousand Americans who have successfully kept at least 30 pounds off for a year or more):
- Ninety-eight percent of Registry participants report that they modified their food intake in some way to lose weight.
- Ninety-four percent increased their physical activity.
3. Walking is the most common form of exercise reported by successful weight loss subjects.
According to the NWCR, their study participants’ most frequently reported form of activity was walking. That’s not to say that other forms of activity (such as interval and strength training) aren’t an important part of a healthy lifestyle, but it is encouraging to know that brisk walking is a simple, affordable, and easily accessible place to start for most people.
4. Exercise itself (even without weight loss) is one of the most powerful preventive health interventions available.
Physical exercise has been shown to reduce blood pressure; decrease the risk for type 2 diabetes, strokes, certain types of cancer, and heart disease; improve arthritis symptoms and sleep disorders, and reduce erectile dysfunction, anxiety and depression. No pill or procedure can come close to providing all these amazing health benefits.
5. Diet is more important than exercise for shedding pounds of fat.
As I often tell my patients, “You can’t outrun your mouth.” Which means – you can eat far more calories in a short period of time than you can ever hope to burn with exercise. For this reason, diet plays a larger role in weight loss than exercise.
6. It’s more important to lose fat than to lose it by following a particular diet.
If diet is so important for losing weight, the next logical question is “Which diet is best?” Interestingly, the answer may be – whichever one you’ll stick to. Now, of course there are some diets that are more nutritionally sound than others – but the benefits of fat loss are so great, that health benefits are achieved even on relatively “unhealthy” diets. In a landmark diet comparison study, Michael Dansinger showed that study participants achieved similar benefits (such as improved cholesterol profiles, blood pressure, and inflammatory markers) from adhering to any of four vastly different diet regimes ranging from low fat, high carb to low carb, high fat.
7. The healthiest diets limit refined carbohydrate and animal fat intake, while maximizing fruit, vegetable, and healthy fats and protein.
I’ve just argued that a variety of diets work if you stick to them, and adherence is the key to fat loss, and even modest amounts of fat loss can have substantial health benefits. So does it really matter which diet you choose? In the long run, yes. Research has shown that there are some common nutritional principles that result in optimal health. The key ones are:
- Avoid refined carbohydrates as much as possible (such as sugar, fructose, and white flour/rice products). Unrefined carbs (such as whole grains, flax, oatmeal, brown rice, quinoa, berries, and cruciferous veggies) are an important part of a healthy diet.
- Avoid animal fats (trans fats). Healthy fats such as olive, fish and nut oils are preferable.
- Eat a diet rich in fiber, fruits and vegetables.
- Choose lean protein sources, including beans, eggs, chicken, fish, pork, yogurt, and fish.
- Limit alcohol intake and opt for water as your main source of hydration fluid.
8. Aim to lose 1 pound per week.
Cutting out approximately 500 calories from your daily caloric needs (established with a calorie calculator or by personal trial-and-error) is about as much as people can tolerate comfortably over periods of time. Diet adherence decreases as deficits exceed 500 calories per day.
9. The optimal, minimal amount of exercise for the average American adult is about one hour of moderate intensity exercise each day.
There is some disagreement on optimal exercise duration – some groups recommend half an hour per day (American College of Sports Medicine), others (such as the Institute of Medicine) a full hour. A review of the various positions and guidelines is available here. In terms of types of activity, there is general consensus that strength training twice a week should be added to moderate daily aerobic activity for best results.
10. You probably don’t need to take any vitamin or nutrition supplements.
Contrary to popular belief, most Americans (even with their sub-optimal eating habits) meet all of their basic dietary requirements with food intake. Non FDA-approved weight loss supplements have not been found to provide lasting benefits for weight loss and are generally ineffective and sometimes dangerous.
Weight loss drugs and surgical procedures may be effective last resorts for those who have failed to achieve results with diet and exercise. New prescription anti-obesity drugs and FDA-approved over-the-counter options are effective at helping patients shed extra pounds, but often come with unwanted side effects such as anal leakage and adverse cardiac events.
In conclusion, obesity underlies most of America’s chronic disease burden but can be reversed with modest weight loss through diet and exercise modifications. Patient adoption of long-term lifestyle changes are challenged by economic factors (e.g. healthy food “deserts” in inner cities), sedentary lifestyles, poor urban planning, excessive fast food and sugary beverage consumption, increasing portion sizes, and high tech conveniences that reduce energy expenditure, among other factors.
Patients are more likely to begin weight loss programs if recommended to do so by their physician, though studies suggest that they take advice more seriously if their physician is not overweight or obese herself. In our efforts to treat obesity, it may be especially important to lead by example.
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A blogger friend of mine referred me to an article about a female runner struggling with gastrointestinal distress. She asked for advice regarding how to prevent the “runner’s trots” and felt fairly mystified regarding its cause. Since up to half of runners face this problem at some point (especially women), I thought I’d post some advice that comes from experience… ahem.
The urge to use the restroom during exercise is caused by increased intestinal motility, likely triggered by any (or all) of the following: jostling of internal organs, relative intestinal ischemia (decreased oxygen getting to the intestines as blood is diverted to the muscles for work and to the skin to cool the body), dehydration, and adrenaline-related anxiety/stress hormones. I’ve noticed that hot weather greatly increases the likelihood of runner’s diarrhea as it contributes to additional blood diversion as well as dehydration through excessive sweating. Basically, don’t be surprised if you need to plan your summer runs around bathroom stops.
That being said, there are a few things that can decrease the urgency and frequency of this unpleasant intestinal drama:
1. Watch what you eat before your run – avoid fiber, caffeine, fake sugar, or anything that generally makes YOU have to move your bowels more frequently (milk and/or soy products are a culprit for some). Ideally, these things should be avoided up to 12-24 hours before you run.
2. Stay hydrated. Get ahead of the game by drinking a liter of water before your run and continue to hydrate during exercise (as appropriate for the climate and your effort level.)
3. Run at a slower pace if the weather is hot. I often find that dropping the pace by a minute or two per mile can magically reduce the intestinal symptoms. Interval training can help you challenge your speed limits while offering active recovery periods for your body to cool down and let your gut chill out.
4. Run in the morning when it’s cooler and you’ve had less to eat. Running after a day full of eating is looking for trouble.
5. Try to evacuate your bowels before your run – this is fairly obvious, but take the time you need to get this taken care of.
If the weather is hotter than 85 degrees, I’d consider running on a treadmill in an air conditioned space.
I found this comprehensive list of strategies to avoid the trots quite helpful. Please check it out – and good luck on your summer runs and races. Perhaps we’ll cross paths at a rest stop near you!
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Cell phones, microwave ovens, wi-fi, smart meters. What do they have in common? They all emit radiation in the radiofrequency range. And they all radiate controversy. Given that these devices are set to become as commonplace as light bulbs, it is understandable that questions arise about their possible health effects. There are all sorts of allegations that exposure can trigger ailments ranging from headaches to cancer. Allegations, however, do not amount to science. And there is a lot of science to be considered.
Let’s start with the fact that an alternating current flowing through a wire generates an electromagnetic field around it. This field can be thought of as being made up of discrete bundles of energy called “photons” that are created as the electrons in the wire flow first in one direction then in the other. Photons spread out from the wire, their energy depending on the frequency with which the current changes direction. The number of photons emitted, referred to as the ‘intensity’ or ‘power” of the radiation, depends on the voltage, the current and the efficiency of the circuit to act as an antenna.
In ordinary household circuits, the direction of the current changes sixty times a second, that is, it has a frequency of 60 Hz, the unit being named after Heinrich Rudolf Hertz, the first scientist to conclusively prove the existence of electromagnetic waves. The photons emitted by such a circuit travel through space and have the capacity to induce a 60Hz current in any conducting material they encounter. Essentially, we have a “transmitter” and a “receiver.” If special circuitry is used to produce current in the range of 10 million (10MHz) to 300 billion Hz (300 GHz), the photons emitted are said to be in the radiofrequency region of the electromagnetic spectrum. That’s because with appropriate modulation at the transmitter (amplitude modulation (AM), or frequency modulation (FM)) these photons can induce a current in an antenna that can be converted into sounds or images.
But what happens when photons in this energy range interact with living tissue, such as our bodies? The greatest concern would be the breaking of bonds between atoms in molecules. Disrupting the molecular framework of proteins, fats and particularly nucleic acids can lead to all sorts of problems, including cancer. However, photons associated with radiofrequencies do not have enough energy to do this, no matter what their intensity. An analogy may be in order.
Consider a weather vane sitting on a roof. It is mounted on a sturdy metal rod, but of course can spin. You decide you want to knock it off the roof, but all you have are tennis balls. You start throwing the balls, but even if you hit the support, nothing happens. You just can’t impart enough energy to the ball to have it break a metal rod. And it doesn’t matter if you gather all your friends, and they all throw balls at the same time. You may have increased the “intensity” of your efforts, but it doesn’t matter, because no ball has enough energy. Of course if you had a cannon, you could knock down the target with one shot. That’s why high energy photons such as generated by very high frequency currents, as in x-rays, are dangerous. They can break chemical bonds! While you are not going to damage the weather vane with the tennis balls, you can surely make it spin, and the friction generated will heat up the base, the extent depending on how many balls are thrown.
Now, back to our photons. In the radiofrequency region, no photon has enough energy to break chemical bonds, but they can make molecules move around, generating heat. The more photons released, the greater the heating effect. This is exactly how microwave ovens work. They operate at radiofrequencies, but at a very high intensity or “power” level, meaning they bombard the food with lots of photons causing the food to heat up. You certainly wouldn’t want to crawl into a working microwave oven and close the door behind you. Similarly, you wouldn’t want to stand right next to a high power radio transmitting antenna, such as used by radio or TV stations, because you could get burned very badly. But the number of photons encountered drops very quickly with distance as they spread out in all directions, so that even standing a few meters from the base of such an antenna would not cause any sensation of heat. Just think of how quickly the heat released by a light bulb drops off with distance.
The “smart meters” that are being installed by electrical utilities monitor the use of electricity and relay the information via a built-in radio transmitter. But the radiation to which people are exposed from these meters quickly drops off with distance, as with the light bulb, and is way below established safety limits. Furthermore, the smart meters only transmit for a few milliseconds at a time for a grand total of a few minutes a day! Cordless phones, cell phones, routers, baby monitors, video game controls and especially operating microwave ovens expose us to similar radiation, usually at far higher levels. Smart meters are responsible for a very small drop in the radiofrequency photon bucket.
It must be pointed out, though, that safety standards are essentially based on the heating of tissues. But what about the possibility of “non-thermal” effects? What if radiofrequency photons cause damage by some other mysterious mechanism? Over the last 30 years more than 25,000 peer-reviewed papers have been published on electromagnetic fields and health, many devoted to non-thermal effects. Health agencies do not find present evidence persuasive of a hazard at ordinary exposure levels, and given the extent of research that has been carried out, it is unlikely that one will be identified in the future.
Although an overwhelming number of studies on cell phones and brain cancer have shown no effect, admittedly some have suggested a barely detectable link. Despite the weak evidence, the International Agency for Research on Cancer has classified electromagnetic fields associated with radiofrequencies as “possibly carcinogenic,” indicating a level of suspicion without any implication that the fields actually cause cancer. This notion pertains to cell phone use and has nothing to do with the far weaker fields associated with wi-fi and smart meters. I would have no issue with a smart meter in my house.
What then about those consumers who claim they have developed symptoms after smart meters were installed? I think it is appropriate to consider John Milton’s poetic view of the power of imagination: “The mind is its own place, and in itself can make a heaven of hell and a hell of heaven.”
Joe Schwarcz, Ph.D., is the Director of McGill University’s Office for Science and Society and teaches a variety of courses in McGill’s Chemistry Department and in the Faculty of Medicine with emphasis on health issues, including aspects of “Alternative Medicine”. He is well known for his informative and entertaining public lectures on topics ranging from the chemistry of love to the science of aging. Using stage magic to make scientific points is one of his specialties.