Massage

There’s one big problem with studying the effectiveness of massage: you can’t control for the placebo effect. “It’s not something where you can do a
double-blind experiment,” admits Trish Schiedel, past president of the Canadian Sports Massage Therapists Association. So you often see results
 by researchers at the Poznan University of Medical Sciences in Poland. They asked volunteers to perform difficult
exercises with both arms, then massaged just one of the arms, and evaluated recovery over the next four days. Subjects said the massaged arms
felt better—but there were no measurable differences in swelling or range of motion. That’s pretty much the story of massage research so far: lots
of anecdotal evidence and a scarcity of hard facts. But in the last few years, some studies have emerged that avoid the placebo problem and
debunk some old myths.
During the many years that muscle soreness after workouts was thought to result from an accumulation of lactic acid, massage was believed to
help flush the acid out. The lactic acid theory is now largely discredited —and even if it wasn’t, experiments published in 2010 by
researchers at Queen’s University in Kingston, Ontario, show that post-exercise massage actually slows down removal of lactate rather than
speeding it up. The reason, according to lead researcher Michael Tschakovsky, is that massage strokes mechanically compress tissue, which
squeezes blood vessels shut and prevents the flow of blood.
To find out how massage does work, researchers at Ohio State University enlisted the aid of rabbits, which aren’t susceptible to the placebo
effect. They first exercised the sedated rabbits by triggering a nerve impulse that causes contractions of a leg muscle. They then used a machine to
deliver “cyclic compression forces” that simulated 30 minutes a day of Swedish massage (the most common type of sports massage). The results
were clear: massaged muscles regained 59 percent of their lost strength after four days, whereas rested muscles regained only 14 percent. The
massaged muscles had fewer damaged fibers and almost none of the white blood cells associated with muscle damage. They also weighed less,
suggesting that massage had helped prevent swelling. Interestingly, the results were much less pronounced if the first massage was delayed for a
day after exercise, suggesting that the sooner you get your massage, the better.
The rabbit results won’t extrapolate perfectly to humans, cautions Thomas Best, the researcher who led the Ohio State study. But these
quantifiable outcomes should help scientists begin to figure out the duration, frequency, and strength of the massage stimulus that produces the
best results. Right now, the right strength is determined by feel, while frequency and duration tend to be a function of how much you can afford. “If
you ask five different therapists, you’ll get five different answers,” Best says. That means finding a good therapist with expertise in sports massage
(not aromatherapy and executive stress backrubs) is essential.

What are the effects of exercise on the brain?

The theme of much of the research described in this chapter is how much influence your brain has on the way you exercise. But it works the other
way around too: the exercise you do has wide-ranging effects on your brain, with the power to alter mood, memory, and even the structure of the
brain itself. Over the long term, there’s not much doubt that exercise makes you smarter. Studies in rodents have shown that physical activity makes
brains develop denser and more complex connections between neurons and stimulates the growth of new brain cells. These effects are especially
important during adolescence and early adulthood, when your central nervous system is developing rapidly and taking the shape it will maintain,
more or less, for the rest of your life.
A massive Swedish study published combed through the records of 1.2 million 18-year-olds who had taken compulsory military
screening exams between 1950 and 1976. The first finding was that aerobic fitness, but not muscular strength, was associated with greater
intelligence. But it wasn’t just being fit that helped—getting fit also offered a major boost. Those who had gained the most aerobic fitness from 15
to 18, as assessed from their high school phys ed marks, scored far better on the cognitive tests than those who had lost fitness. Since 268,496 of
the subjects were brothers, the researchers were also able to determine that the links between aerobic fitness and intelligence were primarily due
to environmental factors like exercise, rather than genetic factors.
The fact that aerobic exercise improves intelligence but strength training doesn’t may come as a surprise. Researchers believe that many of
exercise’s neural benefits relate to whole-body effects such as increased blood flow: getting your heart pumping in a cardio workout carries more
blood, along with helpful growth factors, to your brain. A study by University of North Carolina researchers used magnetic resonance
angiograms to determine that elderly subjects who did regular aerobic exercise had more small blood vessels in their brains, and fewer twists and
turns in those vessels, compared with non-exercising controls. The benefits of strength training, in contrast, tend to be limited to the muscles you’re
using.Although it takes time to rewire your brain, you can tap into some of exercise’s brain-boosting benefits almost instantly. researchers at
the University of Illinois at Urbana-Champaign put 21 volunteers through a set of tests to assess working memory (the ability to remember
something and then retrieve it for use a short time later) immediately after a 30-minute session of either aerobic or resistance exercise, and then
repeated the tests half an hour later. The aerobic exercisers improved their reaction time on the post-exercise test and improved it even more on
the second test; the strength trainers, on the other hand, were no different from controls who hadn’t exercised at all. These findings apply only to the
specific working memory task that was tested, but they suggest that the mental benefits of aerobic exercise start right away.

There are also indications that more (or harder) exercise produces greater cognitive gains. Another study, from Taiwan’s National
Cheng Kung University, found that mice forced to run on a treadmill made greater cognitive gains than mice that ran at leisure on an exercise wheel
(though both groups did improve). But there are limits. Extreme exertion like running a marathon generates stress hormone levels comparable to
those seen in military interrogations and first-time parachute jumpers, which can interfere with some mental processes. Researchers tested 141
runners immediately after they completed the Boston or New York marathons and found that their “explicit memory,” which answers questions like
“What happened an hour ago?,” was impaired. On the other hand, their “implicit memory,” measured by the ability to complete partial words, was
enhanced.
New results in this area continue to be published on a regular basis, so it won’t be long before we’re able to say with certainty why the extreme
stress of a marathon helps some mental processes and hurts others, or which particular exercise-produced growth factors are key to generating
new brain cells. For now, the advice is simple: keep doing all the exercise that’s recommended for a healthy cardiovascular system, and you’ll get a
mental edge as a bonus.

About vitamin D...

D has been the star vitamin of the past few years, piling up study after favorable study even as the claims of its fellow vitamins are steadily
being debunked. According to various studies, vitamin D fights cancer, builds bones, combats heart disease, tunes up your immune system, and
provides a long list of other benefits. Since it’s produced in the body as a response to ultraviolet light from the sun, people who live far from the
equator are particularly at risk of deficiency in winter—which may explain why diseases like lung cancer and breast cancer are most likely to kill you
if you’re diagnosed during those gloomy months. You can get some vitamin D from sources like fatty fish and fortified milk, but the vast majority
comes from either sunlight or supplements.



In a study, researchers from the University of Manchester in Britain asked 99 adolescent schoolgirls to perform a series of one- and twolegged
jumps, then took blood tests to see how much vitamin D they had in their bodies. There was a clear correlation: the more vitamin D, the
higher, faster, and more powerful the jumps. To many, this was confirmation of what they’d suspected for some time: the “sunshine vitamin” could
turn out to be the ultimate natural performance enhancer. But it’s not quite that simple.

Interest in the sun’s potential as a performance booster dates back at least to a rudimentary Russian study in 1938 in which four students
improved their 100-meter dash time by 7.4 percent after a course of UV radiation, while controls improved by only 1.7 percent. In subsequent
decades, German researchers also tried boosting performance using sun lamps and identified vitamin D as the probable cause. But this research
petered out in the 1960s without any rigorous conclusions. Other studies have looked at vitamin D’s links with parameters like reaction time and
muscle protein synthesis. But, according to a review of the topic in Medicine & Science in Sports & Exercise, no studies have ever looked
for direct links between athletic performance and levels of vitamin D indicated by blood tests.
Much of the debate centers on how you define deficiency. According to a 2008 study in the American Journal of Clinical Nutrition, vitamin D
levels in American children and adults appear to have declined since the 1980s, possibly because people spend less time in the sun and drink less
milk. About half of adults now have sub-optimal levels of vitamin D, according to the study. Notably, three-quarters of the girls in the University of
Manchester study were found to be vitamin D deficient, which makes it less surprising that higher levels improved jumping performance. After all,
even a glass of water is performance-enhancing if you’re thirsty.



Several large-scale studies involving thousands of people are now in progress to untangle the cause-and-effect links between vitamin D and
various diseases. Despite the uncertainty, there’s enough evidence to suggest that you should be aware of your vitamin D levels and make sure
you either take supplements or get enough sun. Once you reach “normal” levels, there’s currently no evidence that further vitamin D will make you a
better athlete—but going from deficient to normal could definitely put a spring in your step.

What ingredients do you really need in a sports drink?

If you’re an old-school type who thinks plain water is all you need, consider this puzzling fact: rinsing your mouth with a drink containing
carbohydrates will boost your athletic performance, even if you don’t swallow and can’t taste the carbs.
Of course, it’s not just carbohydrates that you find in sports drinks these days. The latest offerings feature a bewildering array of formulations
aimed at different sports and levels of activity, along with high-tech additives that purport to improve everything from alertness to metabolism. But
you should be wary of the hype surrounding these magic ingredients. The core of any sports drink remains simple, says University of Guelph
researcher Lawrence Spriet. Here are the three key ingredients, in order of importance:

        • FLUIDS: The first point is simple: “If you’re engaging in physical activity you’re going to lose fluids,” says Spriet, who also serves as chair of
the Gatorade Sports Science Institute’s Canadian advisory council. Although the precise link between dehydration and performance is still a
topic of debate, it’s clear that letting yourself get thirsty during exercise will compromise your performance.

        • CARBOHYDRATES: The second element is carbohydrates, which are typically found in sports drinks in the form of glucose or other easily
digested sugars. The goal is to maintain blood-sugar levels and replace glycogen stores in hard-working muscles, which is essential in bouts
of exercise lasting longer than an hour. Sports drinks traditionally contain about 6 percent carbohydrate, about half the level of a typical juice or
soft drink. That’s about as high a concentration as your stomach can handle before absorption is slowed down, according to a recent study by
University of Birmingham researcher Asker Jeukendrup in the journal Nutrition & Metabolism. Newer formulations such as Gatorade’s G2
have cut the carb level to 3 percent, which is more appropriate for people who aren’t pushing hard for hours at a time and thus don’t need the
extra calories.
Scientists have long been puzzled about why carb-filled drinks also seem to help in shorter bouts of exercise, when energy stores
shouldn’t be an issue. Researchers at the University of Birmingham published a study in 2009 showing that cyclists performed better in a time
trial if they rinsed their mouth with a drink containing either glucose or a tasteless carbohydrate called maltodextrin but saw no improvement
from rinsing with an artificially sweetened drink. Brain scans showed that glucose and maltodextrin made the reward centers in the subjects’
brains light up while artificial sweetener didn’t, suggesting that our mouths have previously unknown carbohydrate sensors. Sports scientists
have now begun advising elite athletes to rinse and spit out sports drinks as they approach the end of grueling endurance races, when their
stomachs may be unable to handle drinking anything.

                • SALTS: Electrolytes, which replace the salts lost in sweat, are thought by some researchers to play a role in muscle cramping but are more relevant to post-exercise recovery for most people. “You have to be working really, really hard for the salt to matter,” Spriet
says. Gatorade makes a little-known product called GatorLytes, which is essentially a sachet of salts that you add to regular Gatorade to up its
electrolyte content—but it’s available only to high-level sports teams, since typical athletes simply don’t need it.
For the average person working out at the gym for an hour or less at a time, there’s no need to drink anything other than water. If you prefer a
sports drink, choose one with a smaller amount of carbohydrate (3 percent is better than 6 percent), or simply dilute a standard sports drink with
water. And don’t put your faith in the magical claims of high-tech additives in some sports drinks—because beyond the three ingredients listed
above the science gets a lot weaker. In fact, Gatorade’s relaunch of its product line in the United States coincided with the decision to disband its
U.S. scientific advisory panel in 2009. The new line boasts specialized formulations such as vitamin C to perk you up in the morning, B vitamins to
help you metabolize energy, theanine to improve focus, antioxidants to “protect your body,” and so on. Spriet is unimpressed. “Everyone wants to
make things more complicated, but there’s a reason the basic formulation hasn’t changed in years,” he says. “It’s fluid, sugar, and salt. That’s all it is
—and it works!”

What are the benefits of yoga for overall wellness?

Of the eight “limbs” of classical yoga, formulated over 2,000 years ago, only one relates to physical fitness as we now think of it. The others include
ethical principles, the flow of vital energy, and meditation as paths toward self-knowledge and enlightenment. These days, many people have a
more casual attitude to yoga. But even if you just drop in to an occasional class, you’ll spend time on breathing and concentration exercises that you
wouldn’t encounter in a typical gym routine—part of the discipline’s continuing commitment to a state of wellness defined much more broadly than
the usual fitness markers.


Science, needless to say, seeks to classify and measure these benefits. One theory is that yoga helps to control the “fight-or-flight” response
that physical, mental, or emotional stress triggers in your body. The stress hormone cortisol, for instance, triggers a cascade of physiologic,
behavioral, and psychological effects through the endocrine system; similarly, your nervous system responds to stress by sending signals to elevate
heart rate, blood viscosity, and blood pressure. If these responses are triggered too often, your body gets run down and susceptible to illness.
Several studies have found that yoga programs can lower levels of cortisol throughout the day
compared yoga with “supportive therapy” in a group of 88 breast cancer patients. (In contrast, yoga failed to change cortisol levels in another 2009
study of women with rheumatoid arthritis.) Various other studies have seen positive effects from yoga on outcomes like perceived stress, mood,
and sleep patterns.


Of course, researchers have observed many of the same benefits from non-yogic exercise. A Rutgers University study in 2008 pitted hatha
yoga against strength training in a head-to-head comparison, putting subjects through 50-minute sessions and then measuring the effects on
anxiety, tension, calmness, and other mental health variables at 15-minute intervals afterwards. Both yoga and strength training had positive effects
—yoga improved scores on anxiety and calmness, while resistance training improved all variables. Interestingly, yoga’s impact was most
pronounced immediately afterwards, then began to fade within an hour. Strength training, in contrast, produced effects that intensified as recovery
progressed, suggesting a longer-lasting result.
It’s important to note that the weights session was perceived by participants to be “moderate exercise,” while the yoga session was “light
exercise”—a difference that could explain why weights had a bigger effect. But, lead author Joseph Pellegrino explains, the details of the sessions
were carefully chosen to mimic how people really do weights and yoga, in order to do a real-world comparison.

Other studies have found, in general, more similarities than differences between yoga and other forms of exercise. A review of 81 studies by
University of Maryland researchers in 2010 concluded that “yoga may be as effective as or better than exercise” for a variety of health-related
outcomes but acknowledged a lack of rigorous studies. For now, researchers haven’t been able to isolate and identify any secret ingredients that
yoga offers and other forms of exercise don’t. But it’s clear that, whether you choose a yoga class or a relaxing bike ride along a waterfront path,
you’ll be getting benefits for both body and mind.