Study: Climber's High No Myth

No doubt you have heard of the "runner's high," which is the buzz achieved by an endurance workout. It has long been speculated that this blissful feeling results from the release of endorphin, a natural opiate produced by the body, but it had never been proven and some scientists considered this a myth.

Recently, scientists in Germany demonstrated that two hours of running does indeed cause the brain to release endorphins. In addition, the opiates preferentially bind to the prefrontal and limbic areas of the brain, which are involved with emotional processing and the suppression of pain.

As reported in the journal Cerebral Cortex, ten runners worked out for two hours and then underwent a PET scan. This is similar to a CT scan that digitally dissects the body except a radioactive isotope is injected into the bloodstream and the PET detects where it is metabolically active. In the case of the runners, the scan showed that opiate receptors in the brain after exercise were occupied by far greater amounts of endorphin. This also corresponded to an increase of euphoria and happiness at the end of the runs; the more intense the feelings, the more endorphin was binding to receptors.

While this study was conducted on runners, it also applies to all athletes and you don't have to work for two hours to experience it. Runners, cyclists, and other endurance athletes can fairly easily get into the "zone" after a half hour of working out.

It's fair to say that most climbers feel a strong buzz when they get to the top of a long, strenuous pitch. We may get a similar feeling on easier terrain only after a lot of vertical gain. In the case of crack climbing, that endorphin blast helps us ignore the pain in our feet. Climbers are frequently accused of being adrenalin junkies but we may really just be addicted to endorphin.

Cramps and Myths

The plague of many a runner, cyclist, climber, boater, and just about any other outdoor athlete, muscle cramps suck. But despite all the suffering, the cause of cramps remains poorly understood. Much of the early research, which was largely funded by Gatorade, has been debunked. Yet this weak science was the basis for a massive marketing campaign that resulted in myths that persist to this day.

It's quite likely that many of you believe that cramps are caused by dehydration. Or perhaps you've heard that they result from a shortage of electrolytes, specifically potassium. Maybe it's a lack of minerals (zinc and magnesium). Not enough stretching and massage is another theory.

Alas, all of these have been ruled out as primary causes by the limited independent research that we do have. That's right folks: None of those expensive sport drinks and electrolyte replacement potions will prevent cramps.

Perhaps the most pervasive myth is that if your muscles cramp you weren't drinking enough (insert bottled brand of over-priced salty water). But as Ross at the Science of Sport blog points out, if dehydration and electrolyte depletion were the cause of cramps, more than one or two muscles would seize up. 

In their excellent five-part series on cramps, Ross and Jonathan explain that when we sweat from heavy exercise the concentration of electrolytes in the blood actually increases. In part 4, they present examples of what happens to an athlete under different conditions of exercise and hydration. The short story is that low levels of electrolytes are the result of drinking too much water and there is no need for salt tablets or any similar product as long as you drink when you are thirsty.

As an article in the New York Times sums all this up, the leading working theory for the cause of cramps is muscle fatigue combined with an imbalance of the nerve signals. These faulty signals can result from numerous causes including too little vitamin D (needed to control excess calcium, see my post on fatigue), inadequate carbohydrates (which you can get without fancy energy bars and drinks), and a host of other factors including genetics, age, menstrual cycles, and even psychology.

The bottom line is that the sport scientists know what doesn't work, and that includes bananas (Super Bowl notwithstanding), but they don't have clear answers yet on how to prevent cramps. The best advice is build up to an event with proper training (don't run a marathon if you've only been doing 10 Ks), stretch regularly especially if you have muscles that tend to cramp (helps relax the muscle cells), and ensure adequate carbs. Of course, if you like spending money on placebos, feel free to support your favorite snake oil purveyor too.

Avalanche Beacon Alert

Last week, the French web site Pistehors.com posted an advisory that has been sent to owners of Ortovox F1 beacons. It warns that these older analog beacons can search just fine but there's a chance that newer digital beacons (nearly all that have been sold in the past 5 years) may not find them when buried by an avalanche. Since many skiers wear a beacon like it's a cloak of invincibility, this should be a scary thought…immobilized under four feet of snow, slowly losing consciousness, and realizing that your friends can't find you because you're wearing an old beacon.

While this Ortovox alert may sound alarming, in truth it's old news and it applies to all older beacons. There are two major issues: signal drift and beacon fragility. And few skiers are aware of either problem.

Although all beacons sold in the past two decades broadcast and receive on the 457 kHz frequency, the newer beacons are much more intolerant of any variation. The ETSI standard requires all beacons to search in this range +/- 80 Hz. Unfortunately, with time and lots of small bumps, some beacons can end up broadcasting outside of this margin of error. The older analog beacons can still receive such errant signals. But many of the newer digital ones cannot.

The Pieps DSP has a unique feature that can measure the signal from other beacons and tells you how close they are to the ideal. But this test must be performed in advance--it does you no good at the trailhead. If your beacon is over or under by 50Hz, it must be sent in for repair. And for most older analog beacons, such as the F1, spare parts are no longer available. Hence the Ortovox advisory.

These analog beacons are not obsolete. In the hands of an experienced searcher, they can be just as fast as any of the fancy new digital beacons. But if you don't test them for drift, they can be a safety placebo.

And herein lies the second major problem with avalanche beacons: they are far more fragile than most people realize. The ETSI standard (ETS 300-718) only requires that a sample beacon operate properly after 6 drops from a height of 3 feet onto a wooden floor. For a piece of lifesaving equipment, that is a very low durability requirement. Skiers likely do not realize how easy it is to damage their beacons. It is quite possible to damage them internally so that they can pass a beacon check at the trailhead (you do one every time, right?!) but malfunction when the shit hits the fan.

That Ortovox France felt it necessary to send owners of their F1 beacons an advisory brings up a overarching problem with avalanche beacons. The outdoor industry as a whole is doing a poor job of educating consumers on what beacons can and cannot do. On his WildSnow blog, Lou Dawson recently discussed 3 myths of avalanche survival: beacons ensure rescue, being buried by an avalanche is no big deal, and you'll be fine once uncovered.

Consumers are sold these $200 to $500 electronic miracle boxes without the knowledge to use them safely. Sure the CDs that come with most beacons now cover the basics adequately but they certainly don't discuss any of the above. Magazines just focus on the glitz without talking about real issues that their advertisers would prefer left unsaid. Movies show gonzo skiers and boarders on gnarly terrain but never, ever the consequences. Store employees seldom get cliniced on more than how to get the box to the cash register, along with add-on sales of a shovel, probe pole, and perhaps an AvaLung.

Even avalanche education courses have focused more on what to do after you've screwed up than how to avoid the problem in the first place. A recent study showed that sidecountry skiers are entirely unprepared for what lays outside of ski area gates. And this same group is now targeted with price point beacons so they can have the illusion of being safer.

With this season shaping up to be the worst in North American history for avalanche fatalities, perhaps the outdoor industry will re-prioritize how to educate consumers about backcountry safety. But that could affect too many bottom lines so I'm not holding my breath.

Lactic acid is your friend

Everyone knows that lactic acid and lactate are evil, right? After all, lactic acid causes the "burn" and fatigue. And one of the goals of training for many athletes is to raise their lactate threshold. That's what we've been told for decades so it must be true, right?

In fact, over the past decade the science keeps heaping on that both lactic acid and lactate are far more beneficial than detrimental. Although the lactate level in the blood during exercise has long been used as an indicator of aerobic fitness, this is now considered to be the result of correlation rather than causation. 

Since lactic acid, which quickly becomes lactate while spinning off a hydrogen ion, is a major topic in training for all outdoor athletes we'll be revisiting this topic in the future. For the time being, the basics of "lactate threshold" training--in particular, intervals--remain sound even though the reasons for them are changing.

In the meantime, this recent study provides a strong indication that lactate is essential for the release of human growth hormone. Check your spam folder and you'll probably learn that HGH is responsible for innumerable health miracles. And read the sports and entertainment news pages to find that it's a favorite juice to shoot up for desperate athletes and has-been actors.

What this study found is that 82% of people who are incapable of producing lactate while exercising (a rare condition called McArdle's disease) also do not produce HGH during their workouts. It strongly suggests that higher intensities, which produce more lactate in a given time period, can be more healthful than low-intensity exercise. 

The bottom line: don't fear lactic acid or lactate.