Golden Brown, Part III: Make Like a Tree and Leave

Researchers who follow hunter-gatherer tribes in tropical and dessert areas have found a nearly universal pattern: during the very hottest hour or two of the day, the members of the tribe get out of the sun completely, to relax and eat in the shade.

Over the course of a summer day, the UV index – the amount of UV radiation reaching ground level – varies hugely. At 12:30pm today in New York, for example, the UV index was at 10, enough to cause burns in just 10 minutes, blazing through even strong sunscreen. Whereas by 1:15, the index had dropped to a 6, allowing for a half hour before burning without protection, and for several hours of happy sun time with a layer of (full-spectrum) sunscreen applied.

A team of outdoorsy engineers in New Zealand recently released a free app, UV Lens, which provides daily hyper-local UV forecasts. With the app in hand, you can easily plan your schedule to mimic the wisdom of our hunter-gatherer ancestors: enjoy the sun in the morning, take a brief, strategically timed mid-day lunch break in the shade, and then head back out once the very highest UV stretch of the day has passed. That way, you can spend far longer outside overall, while still greatly reducing the risk of sun-damage and burn over the course of the day.

Golden Brown, Part II: Screened

As I shared in Part I, getting some sun is good for you, at least if you’re smart and careful about it.

Your first step to that end: get some good sunscreen.

Sunlight is made up of two kinds of ultraviolet rays: UVA and UVB. It’s the latter, UVB, that causes sunburns, so for decades sunscreen was designed to block UVB. But more recently, research has shown that UVA rays, which penetrate deeper, also substantially increase skin cancer risk, and cause wrinkles. (The EPA estimates that up to 90% of aging-related skin changes are actually caused by a lifetime’s exposure to UVA.)

Good sunscreen is therefore ‘full spectrum’ or ‘broad spectrum’, and blocks both UVA and UVB. While those were previously specialty products, in the last year or two, almost all the major sunscreen brands have released reasonably-priced, widely-available versions that block both spectrums. Make sure you only buy sunscreens that do.

Three more sunscreen tips: slather it on, do it often, and stop going nuts with the SPF.

According to the American Academy of Dermatology, most people apply only 25-50% of the amount of sunscreen that they need per application, which reduces an SPF 30 sunscreen to an SPF 3. SPF ratings are based on applying two milligrams of sunscreen per square centimeter of skin. Which is a lot. Basically, you should briefly look like Casper each time you apply a layer if you want your sunscreen to actually do anything.

Next, a sunscreen is FDA-certified as ‘water resistant’ if it can hold up to 40 minutes of swimming or sweating. After that, all bets are off. So, while you’re on the beach, you also probably need to reapply every hour or so.

And, finally, just buy some SPF 30; after that, the numbers get kind of meaningless. A few years back, Procter & Gamble even sent a letter to the FDA, asking that the numbers be capped at 30, because real-world and laboratory light conditions are different enough to make higher SPFs of “dubious value” that are “at best, misleading to consumers.”

So, to recap, buy some SPF30 full-spectrum, water-resistant sunscreen. Put on a bunch, and keep reapplying. And then enjoy the sun!

Golden Brown, Part I: Get Some Sun

With beach weather upon us, I’m spending this week on a roundup of summer sun tips, with the science behind each, so you can make smarter choices about what works, and what doesn’t.

First up: get some sun. It’s good for you.

While people completely ignore most public health advice, it seems we’ve actually taken warnings about the dangers of tanning too much heart.

Excess sun exposure (and sunburn) increases the risk of skin cancer. But too little sun exposure dangerously decreases your level of vitamin D (which your skin naturally produces when exposed to sun), increasing the risk of a slew of other cancers and heart disease.

As one recent review study concluded, “the overall health benefit of an improved vitamin D status may be more important than the possibly increased melanoma risk resulting from carefully increasing UV exposure.”

In other words, it’s healthy to get back out in the sun. Just be smart and careful about how you do it. Tune in tomorrow, and learn how to wear (good) sunscreen, the right way.

Suck it Up

For the most part, you should run the other direction from crash diets, fast fixes, and “one weird trick” solutions. But with summer upon us, there is at least one exercise you can still deploy in the last couple of weeks that will make you appear noticeably slimmer when you hit the beach.

It’s called the ‘stomach vacuum’, and it’s an old bodybuilder standby, used by competitors to achieve the waspish waist that was the hallmark look of that sport’s golden era.

The stomach vacuum works the transversus abdominis (or TVA), a deep postural core muscle that serves as essentially a natural corset, holding in your guts. Improving the maximal contractive strength of the muscle also increases the muscle’s tone – its degree of resting contraction. Which, as a result, will carve an inch or two visually off your waistline, even in just two or three weeks.

Here’s how it works:

  1. Ideally, do this first thing in the morning. Or, at least, on an empty stomach.
  2. Start lying on your back, with your feet on the ground.  
  3. Take a full breath, then exhale through your mouth until you've blown out all the air.  
  4. Once your lungs are empty, pull your bellybutton down to your spine, as hard as you can. Really pull it down; the harder you pull, the closer to your spine your bellybutton gets, the better this works.
  5. At the same time, try to make your chest as big as possible (i.e., lift your chest up), though while still pulling down hard on your bellybutton.
  6. Hold that for 15 seconds.  
  7. Then relax, breathe normally for 15-30 second, and repeat, 2-4 times more.

If you stick with this exercise over the course of the summer, you can slowly increase the duration of each hold, adding 5-10 seconds each week, until you’re holding for 60 seconds for each of your 3-5 sets.

Again, this should drop two inches off your waist in just two to three weeks. And, as a bonus, engaging your TVA improves power transfer in athletic movements, and may even protect your low back from tweaks and injuries.

Suck it up, indeed.

Hot & Cold

About 40 years ago, Dr. Gabe Mirkin coined the acronym RICE – Rest, Ice, Compression, Elevation – which has been the standard treatment protocol for most athletic injuries ever since.

Recently, however, a slew of studies have begun to show that icing actually delays healing. (For some good examples, see this one and this one.) The studies are persuasive; so much so that even Dr. Mirkin has changed his mind, updating RICE to the new (albeit much less pronounceable) MCE: Movement, Compression, Elevation.

In short, while inflammation was initially considered to be a source of damage (hence icing, which reduces that inflammation), scientists increasingly understand that inflammation is actually a key part of the healing process, with inflammatory cells called macrophages releasing hormones into the damaged tissue to help with repair. (Here’s a recent study on that process.)

Eagle-eyed readers will note that Mirkin isn’t just dropping icing, he’s also swapping rest for movement (or, more specifically, for “move safely when you can as much as you can”). Continuing to gently move an injured joint or muscle promotes the flow of fluid into and out of the area around the injury (which allows those macrophages to get in when they need to work, and to depart once they’re done), and prevents the injured tissues from wasting as they would with complete rest.

So throw out that stack of old ice packs in your freezer, and start thinking of creative ways to say “MCE” out loud.



In exercise science, there’s a principle known as SAID, or ‘specific adaptation to imposed demands’: when your body is exposed to a stress, it responds by improving your biomechanical and neurological ability to handle that stress.

Start doing pull-ups regularly, and your body will get better at pull-ups, increasing the strength in your lats and biceps, and reinforcing the tendons in your shoulders and elbows.

But SAID also dictates that adaptation is specific. So while practicing pull-ups will make you better at pull-ups, it won’t necessarily improve your ability to pull yourself up a mountain face while rock-climbing.

For years, the gospel of SAID kept most athletes locked into the most literal version of their sport. If you wanted to train for a marathon, you’d simply go for increasingly long runs.

Let Me Be (Less) Specific

Over time, however, scientists began to discover that adaptation wasn’t quite as specific as initially believed. Because most sports depend on a constellation of intertwined skills and abilities, other types of training could often develop those constituent skills and abilities more effectively than simply (or solely) practicing the goal sport itself.

Rather than just going for long runs, for example, marathoners began to integrate interval and tempo work – practicing the skill of running faster for short distances, and then working on sustaining a higher pace for gradually greater distances. Though neither type of run was as ‘specific’ as a long-distance jog, they helped runners improve faster than long-distance jogging alone, and athletes began to set new records, year after year.

As athletes and coaches further experimented, they began to see that even more distantly-related variants of the initial task could be valuable. In the early days of the competitive marathon, for example, weight-training was considered anathema to running. By now, virtually all marathoners have extensive weight-lifting programs. And the details of those programs have evolved over time, too. While runners initially used light weights for a large number of reps (reasoning that it more closely mirrored the endurance-heavy nature of the goal task), now elite runners instead tend to focus on developing skills like power-endurance in the weight room. Though a heavy set of cleans is a far cry from a long-distance jog, it turns out to pay greater dividends on the road than time spent doing multiple sets of 20-rep leg extensions.

Far, Far Away

Today, some of high-level athletes’ training modalities seem ridiculously distant from the sort of specific training that once dominated the show. For example, hyperthermic conditioning – or, sitting in a sauna or steam room – has recently come into vogue. Scientists discovered that regular time in the sauna boosts plasma volume and blood flow to your heart and muscles, increasing endurance in even highly-trained athletes.

In other words, while adaptation may be specific, a modern and science-based understanding of training has a much broader definition of what, exactly, ‘specific’ might mean.

Most of us have limited time (and energy) to devote to fitness, so it makes sense for us to focus on the things that give the most bang for the training buck. And from that perspective, a few sessions a week of strength training and metabolic conditioning are all you need to get into great shape.

But because Composite works with pro, semi-pro, and serious amateur athletes, we’re also always on the lookout for things (like hyperthermic conditioning in the sauna) that can help juice out additional percentage points of performance gains.

That’s what led me to a series of recent experiments with apnea tables, an idea borrowed from the world of spearfishing and free-diving (a sport of diving to SCUBA depths while simply holding your breath).

Let’s Get Metabolic

To understand why apnea tables work, you first need to know a bit about energy metabolism. When we work out at high levels of intensity, our bodies route around our cells’ mitochondria (which generate energy in a more sustainable, but slower, way) to create energy directly, in the rest of the cell. That process, anaerobic metabolism, is much faster, though it creates an increasing build-up of lactic acid as a by-product, called metabolic acidosis. Eventually, as enough lactic acid builds up, we hit what’s called the lactate threshold: we ‘feel the burn,’ and need to slow down or stop.

But where that threshold is, exactly, varies from person to person. In short, the higher the threshold, the more metabolic acidosis you can tolerate, and the greater your exercise endurance.

As you exercise, your body also creates carbon dioxide, or CO2. And CO2 is a buffer against lactic acid. So the higher the level of CO2 in your blood, the more metabolic acidosis you can tolerate.

We’ve long known that’s one of the ways endurance training works: you increase your tolerance of CO2, which increases your tolerance for metabolic acidosis, which increases your performance and endurance.

Just (Don’t) Breathe

But while you can improve CO2 tolerance indirectly through exercise, it turns out you can also train it directly.

When you’re holding your breath, your body doesn’t actually monitor the amount of oxygen in your blood. Instead, it monitors the amount of CO2. As it climbs, you feel like you need to breathe. But that feeling has a lot of margin of error built in. Most people can only hold their breath for 30-45 seconds, due to CO2 tolerance, but it takes a full 180 seconds, or three minutes, before your oxygen levels really begin to drop.

So free-divers and spearfishers have developed ways to improve CO2 tolerance, in an attempt to hold their breath for longer and longer durations. (With practice, a decent free-diver can go 5-6 minutes on a single hold.)

Their main training tool is called an apnea table, which alternates static periods of breath-hold with decreasing periods of recovery breathing.

It looks like this:

Round 1 – Hold 1:00 – Breathe 1:30

Round 2 – Hold 1:00 – Breathe 1:15

Round 3 – Hold 1:00 – Breathe 1:00

Round 4 – Hold 1:00 – Breathe 0:45

Round 5 – Hold 1:00 – Breathe 0:30

Round 6 – Hold 1:00 – Breathe 0:15

Here’s a good iPhone app that does a more tailored, dynamic, and easily counted version of the same thing. (It’s what I and my athletes have been using.)

With increasingly brief durations to catch your breath between holds, and less time to flush the carbon dioxide from your blood, your CO2 level will slowly climb over the course of the protocol. Which, in turn, builds your ability to tolerate the increased CO2. (Nota bene: if you’re doing it right, you should likely feel a little light-headed by the end. Sit or lie down while you’re practicing, so that you don’t injure yourself if you happen to pass out. And never, ever try this in water; drowning is tacky.)

From what I’ve seen, most free-divers recommend trying this just once a week, as well as a weekly workout on an oxygen table (where the breathing periods are constant, but the holds increase). While I suspect the latter would be beneficial to endurance, too, I’ve focused my experiment solely on the CO2 / apnea table, to better isolate its effects.

Great Success!

And, in short, the effects have been pretty impressive. My 500m row had held steady at 1:47 for the past few years. (I know, I know. At 5’6”, rowing isn’t exactly my sport.) After just six weeks of apnea table practice, however, I pulled a 1:42 – a whopping 5% improvement. And, at least as importantly, a slightly slower row (2:00/500m) now seems far, far easier in terms of perceived exertion, leaving me much less gassed when one shows up mid-workout.

I’ve seen similar improvements on my running and metabolic conditioning times, and the four athletes on whom I’ve been testing the apnea tables have also seen 3-8% performance bumps across the board.

At less than 15 minutes of weekly time commitment, it seems more than worth trying out. If you do, let me know how it goes; I’m definitely curious to test this further, and will report back with more data once I do.

Still Fast

As I mentioned a few days ago, I’m now testing out the Fast Mimicking Diet, an intermittent, very-low-calorie five-day semi-fast, which research is showing may have powerful effects on long-term health.

As compared to the roughly 3500-4000 calories I eat on most days, 725 calories seems very low calorie indeed.

My fast compatriot Jessie and I collectively decided that our best strategy would be to further subdivide things into a series of daily intermittent semi-fasts: eating 125 calories through the morning and afternoon, then enjoying a large 600-calorie dinner. Last night, for example, we had scallops in a lemon-butter sauce with mashed celery root and braised kale. Which was both delicious, and served in large enough portion that I almost couldn’t finish eating it.

Thus far, I’ve also stuck with my workouts as previously programmed. Yesterday, despite running on fumes, I managed to pull a 20-pound PR on the sumo deadlift. Though, following that, and feeling slightly lightheaded, I also didn’t quite stick the dismount stepping down from a weighted step-up, leading to a five-foot backwards sprawl that narrowly avoided landing under the 135-pound barbell.

Fortunately, I don’t have any more heavy lifting scheduled during the fast – just a more conditioning-focused workout today, and two weekend runs (one intervals, the other a longer tempo jog). I’m not sure how those will work out, though it’s probably better to fail by having to walk part of a sprint than by being crushed to death by dropped weights.

Think Fast

As I’ve previously written, I’ll try pretty much any research-backed fitness idea, as I find that playing human guinea pig gives me a real-world perspective on trends far better than simply observing from the sidelines.

Recently, the Fast-Mimicking Diet (or “FMD”) has been getting a bunch of press. Based on a set of studies out of USC’s Department of Biological Sciences, the FMD aims to provide the upside of a monthly five-day water-only fast, without the whole not eating food part.

That said, while the diet isn’t a true fast, it does involve draconian reductions of both protein and calories. There’s a slightly milder (1090 calories) day of induction, followed by four more days of very restricted (725 calories, 16g protein) eating.

In mice, the diet yielded muscle rejuvenation, increased bone density, fewer malignant lymphomas, a serious uptick of immune system function, and longer life expectancy. Follow-on studies of humans showed similar effects, with biomarkers like visceral fat, C-reactive protein, and immune function all improving markedly after a semi-fast.

So, starting tomorrow, I’m kicking off June by trying it out myself. And, frankly, I suspect it’s going to suck. As Jessie (my co-guinea pig on this) pointed out, I currently eat about 4000 calories daily (what? I have a fast metabolism), so this cutting back, percentage-wise, is going to be a more serious kick in the pants than it would be for most.

I’ll be blogging about my experience and the results, though advance apologies if the lack of brain glucose and general ‘hangriness’ drops the quality of posts below my (admittedly already pretty low) regular bar.

In the meantime, I’m off to eat until it hurts.

In the Hopper

One of Greg Glassman’s big innovations in creating CrossFit (whatever you think of its many pros and cons) was to set out a clear definition of what fitness actually is, as well as a set of clear proposals for how we might test it.

One of those proposals was the hopper test: in short, you write every exercise, every sport, every possible physical feat on pieces of paper, and drop them into a bingo hopper. Then you randomly draw out, say, ten of them, and make people perform those ten, randomly-selected physical tasks. By Glassman’s definition, the ‘fittest’ person would be the one who performed best, overall, on those randomly selected tasks.

But Glassman also observed that the hopper test has an interesting side-effect. Because we all know what we’re good at, and what we aren’t, if you were to actually participate in a hopper test yourself, you’d have a very clear idea of what you most wanted to see come out of that hopper, and what you’d most dread.

Perhaps you crush heavy weightlifting, but can’t run to save your life. Or perhaps you’re great at moving yourself around in space, but atrocious at anything involving flying objects and hand-eye coordination.

From that, Glassman posited what he though would be the theoretically best way to improve your athletic ability: imagine the five things you’d least want to see come out of the hopper. Then work on those, deliberately and intensely, until you mastered them to the degree that they became the things you actually most hoped to see selected. Then move to working on the next worst five.

In real life, that approach doesn’t work. Glassman mentioned he’d tried it briefly with his early personal training clients. And, in short, it’s so demoralizing to suck badly at everything you do, takes such an emotional toll, that his clients would simply drop out rather than repeatedly face those most-feared tasks.

So, instead, CrossFit was built on the idea of broad variation. With a wide array of stuff thrown at you, you’re forced to address the things you suck at, while also feeling buoyed up by getting to excel at the things you do well.

Still, that always reminded me of an observation from my trumpet teacher at Yale, a professor in the School of Music. He pointed out that if you walked up and down the practice room halls, you’d think you were listening to the New York Philharmonic warming up. Left to their own devices, students spent time practicing what they already did well, rather than take on the hard task of improving the areas where they fell short.

For me, running has always been my biggest athletic weakness. I dreaded the timed mile in gym class, and would demure when invited to join friends for a weekend jog. Sure, I pushed myself to do it when necessary, at one point even (unexpectedly) doing a half marathon. But I sure as hell wasn’t going running if I had the choice.

That’s why, this year, I resolved to stop sucking at running. It’s the reason I took on several months of SEALFIT, and the reason I’ve been following Power Speed Endurance programming ever since.

So far this year, I’ve almost certainly run more than I did in the decade prior. And though I’m still not a good runner, still won’t be lining up at a road race start anytime soon (even for a 5k, much less a marathon), I can definitively say it’s paid off. My times have improved, and my distances have increased. But, more importantly, it no longer seems like something I tell myself I “can’t” do. Today, I ran a mile as part of my workout warm-up, and another as part of the cool down. And though that isn’t much, for the first time, I found myself setting out on each run with no trepidation. I knew I’d be totally fine. And I felt ready to consider what might come next on the most-feared list of my personal hopper test.

Break Time

If you’re an average, 180-pound person, all the capillaries in your body – the smallest blood vessels, where oxygen and other nutrients are exchanged with cells – can together hold about 3 gallons of blood.

But blood, like water, is heavy. So you evolved into an evolutionary compromise. Your body only contains about 1.5 gallons of blood at a time; much lighter to carry, but only half of what you need to provide for your whole body at once. Fortunately, your body also evolved a smart system of hemodynamics, a combination of forces that sends that blood to capillaries as it’s needed.

At the front end, your heart pushes oxygen- and nutrient-rich blood through your arteries.

Then the movement of your muscles pulls that blood from your arteries into your capillaries, to feed individual cells.

In other words, while your heart is circulating blood all the time, the oxygen and nutrients only make it to cells when the muscles around them are moving.

That’s one of the major problems with excessive sitting: without movement, your cells are starving.

But that’s just one problem. After 30 minutes of sitting, your metabolism slows down by 90%. A few hours in, you’ve got increased blood triglyceride and insulin levels, and reduced (good) HDL cholesterol and lipoprotein lipase (an enzyme that breaks down fat in your body).

So perhaps it shouldn’t be surprising that people who sit more are sicker and fatter than people who don’t.

What’s more, that’s independent of exercise. Even between people who work out for the same number of hours weekly, a greater number of hours spent sitting each day correlates with an increase in both body mass and all-causes mortality. Studies have tied sitting to huge increases in everything from type 2 diabetes to cardiovascular disease and cancer.

For example, excess daily sitting increases your risk of lung cancer even more than the second-hand-smoke effects of living with a smoker.

All of which is bad news, because we apparently really love to sit. The average desk worker spends 7-8 hours a day sitting at the office, then comes home to sit down for another 5 hours of daily TV.

Fortunately, the solution is simple: get up frequently and move around.

Research has shown that even short breaks (a couple of minutes) at low intensity (walking to the bathroom, or simply standing up) make a huge difference. One study showed that, the greater the number of breaks taken, the lower the waist circumference and BMI, and the better the blood lipids and glucose tolerance.

Of course, once you get into the flow of work, it’s easy to forget just how much you’re sitting. That’s why you need a gentle nudge.

Breaktime for Mac or Rest for Windows will take over your screen at whatever interval you select, reminding you to stand up, shake it out, go the bathroom, grab a water or coffee, or similarly get that mini-dose of movement it takes to get your body back on track.

Getting up and moving every 30 minutes is a pretty small habit. But it pays big dividends in your short- and long-term health.