PhysiKcal Fitness: Weekly Features
The problem with the
"Biggest Loser"
Can exercise make you more full?
WEEKLY ARTICLES
WEEK 1 - Page 3
The problem with the "Biggest Loser"
WEEK 2 - Page 5
How many reps?
WEEK 3 - Page 7
What Food should i eat?
WEEK 4
WEEK 5
WEEK 6
WEEK 7
WEEK 8
WEEK 9
LATEST SCIENCE NEWS
Page 6
Can exercise make you feel more full?
Page 8
Why do viens bulge during exercise?
Page 10
Diet diary doubles weight loss
Page 12
Exercise & Oesteoporosis
Page 14
Humans - The Fatest Ape
Page 16
Exercise and no smoking prevents alzheimers
Page 18
Bye Bye Bat Wings
Page 20
Body Image distortion - are you at risk?
Setting Realistic Goals:
The problem with the "Biggest loser"
By Nick wachter (Personal Trainer)
Too often as a trainer I hear people setting very unrealistic target. Partly it is due to television programmes such as the biggest loswer, in which very over weight participants lose alot of weight quickly. These guys have chefs cooking for them and personal trainers on hand 24 hours a day. Everything that may help them to reach their goal is there for them. for the rest of us however its a little bit harder.
The contestants in the biggest loser did not gain 15 stone of weight by eating the wrong type of bread or doing "not quite enough exercise". they gained the weight by a very very high calorie diet and a very very low activity level. Thus when they are given the opportunity to massivley increase their activity and dramatically reduce their intake (calorie consumption) they can lose an amazing amount of weight. Lets take nothing away from them. What they do is not easy and they put theyre all into it. But they have no distractions, massive amounts of motivation and are surrounded only by people who arw working towards the same goal as them or who want to help them work towards their goals (the trainers).
Where are the nappies that need changing? The 5 year old having a fit because they dont want to put their socks on, even though your already late going to work? Where are the work collegues who always bring in the sweets? What about the lack of healthy foods that are easily available to the competitors.
When it comes to setting goals you have to know what is realistic and what isnt. For most people losing 1-2 sotne a year is a challenging goal. Thats 0.5-1lb a fortnight. Most people seem to udnerstand that this is a reasonable amount of weight to lsoe over a year and from speaking to many clients over the years these are the figures they have in mind for long term weight loss.
However the majority of times people ask me in social settings "how much can i lose in two months" and i always ask them a question bac. What do you think you can lose and how much do you want to lose. Often the answer is a stone or two. Thats the equivilent of 4-8 stone a year. Thats alot, even for a biggest loswer competitor.
The MATHS
3500kcals in 1 pound of fat & 14 pounds in 1 stone.
so 3500 x 14 = (3500x 10 = 35,000 + 3500 x 4 14,000 = 49,000kcal)
To lose one stone you have to either burn up or consume 49,000 less than you are at present.
To do that in 2 months means you have to split 49,000 calories over 60 days. Thats just under 1000 kcals a day. To do that exercise wise you would have to run/exercise for about 2 hours (assuming your level of fitness is low/ average) every single day for 60 days in a row. Seems a little unrealistic right, Especially if at present you dont exercise. Not to mention the likelyhood of injuries from doing so much.
Or you can take it out of your diet? Removing all junk food, calorific drinks (pop etc) and spreads etc can easily take 500kcals out of the average persons diet every day. Thats if you stick to it perfectly for 60 days and nights with no slip ups.
So we have to eat perfectly healthy with no slip ups and train for 1 hour everyday (half from diet half from exercise) in order to achieve our goal. Again this would be impossible for most people who werent in the biggest loaser camp.
Weight loss should be a long term life style change. Study after study has shown that slow steady weight loss is much more succesfull than fast drops in weight.
The advice is be SENSIBLE, be REALISTIC and find something you enjoy doing? It doesnt have to be the gym, Walking Badminton, Rock climbing and make small changes to your diet. every month cut out one of the bad tings things you eat and replace it with a healthier substitue.
Author
Nick Wachter
BA Hons
www.ScientificAmerican.com
Can Exercise Make You Feel More Full?
A study of fat swimming and running rats indicated that exercise induces brain chemistry changes that decrease appetite
By Katherine Harmon
A RUN A DAY?: New research in rodents reveals how exercise might spur a chemical shift in overweight individuals that would put hunger on hold.
By a simple food-in/energy-out model, a run on the treadmill or swim in the pool should make you want to eat more. But recent findings have suggested that exercise can actually help to slow overeating. And a new study presents evidence that the body's physiologic response to exercise can help retune the nervous system's cues and make the body feel less hungry, rather than more so.
Hunger is a complex sensation, but it is determined in part by neurons located in the hypothalamus, which send signals to the brain telling it that you're either hungry or sated. Those neurons get their message from hormones, including insulin and leptin. When the body develops a resistance to these messengers, people become more prone to overeating and weight gain. And scientists have begun to suspect that cellular inflammation might be at least partly responsible for allowing these signals to get out of whack.
Researchers behind the new work found that "physical activity reorganizes the set point of nutritional balance through anti-inflammatory signaling," they reported in their paper, which published online August 24 in PLoS Biology.
The key to the signaling seemed to be interleukin-6 (IL-6) and IL-10, which are proteins secreted by immune cells. The compound IL-6 gets released from muscles when they contract and has been found to "play a central role in the regulation of appetite, energy expenditure and body composition," the researchers noted. But just how these compounds might be acting on the nervous system's components, such as the hypothalamus, remained murky.
To further explore this association, the Brazil-based research team examined energy use in both lean and obese rats that swam or ran on a treadmill. After the exercise, both the lean and the obese rats had lower insulin levels, but the rats that had been fed to become obese went back to eating more like their lean peers. By sampling the biological profiles of some of these animals, the scientists found that the exercise had changed the obese rats' hypothalamic chemistry, which included boosting IL-6. Rats that were given an antibody to inhibit IL-6 before exercise did not show the same biochemical or feeding patterns afterward.
"These molecules were crucial for increasing the sensitivity of the most important hormones, insulin and leptin, which control appetite," José Carvalheira, of the Department of Internal Medicine at the State University of Campinas in São Paulo and coauthor of the new study, said in a prepared statement.
Although the intense bursts of exercise seemed to spur these noticeable shifts in chemical profiles, in this study the activity only reduced the food intake in rats that were already obese, and the activity did not seem to directly relate to immediately apparent weight loss. But this chemical change alone suggests that physical activity "could help to reorganize the set point of nutritional balance and, therefore, aid in counteracting the energy imbalance induced by overnutrition-related obesity," Carvalheira and his colleagues noted in the study.
Click here for the link to the following articles.
You Might Also Like:
Does Inflammation Trigger Insulin Resistance and Diabetes?
Leptin Surge Produces Overweight Offspring from Underfed Moms-to-Be
When the Levee Breaks: Protein Overwhelmed by Overeating Leads to Metabolic Diseases
Running Rats Reveal Cardiovascular Risk Factors
Do I look fat in these genes?
Exercise can cancel out effects of 'heavy-weight' DNA Obesity is now just as much of a drag on health as smoking The
Mind-Body Problem
How Many Reps?
By Personal Trainer Nick Wachter
As a personal trainer this is the one question we get asked on an almost daily basis. The answer I give to everyone initially is always the same “As many as you can”
We do use different reps for different purposes
Power = 6-9 reps at 30-50% of 1 rep max
Strength = 7-15 Reps at 70% of 1 rep max
(dependant upon an individuals proportion of fast to slow twitch fibre type)
Endurance = 15+ Reps at 50% of 1 rep max
However this is way way to technical for most of us and our goals. If were looking to gain strength then use between 8-12 reps and looking to tone then use between 10 and 20 reps.
The most important factors (way more important than how many reps you do) is how well you perform the set and how much effort you put into a set. Every single day we see, mainly guys, discussing how many reps and sets they do of which exercises, as if somehow the secret of getting into great shape lies on a mystery number they are only days away from discovering. At the same time as discussing on a daily basis with every other person every single day how many reps and sets they do, they generally have poor technique (uncontrolled movements, too fast, short range of moment) and or do not work that hard.
The key is too work as hard as you can on every set aiming for a specific number, but never stopping at that number. If I aim for 12 reps I am very very very unlikely to ever hit 12.
Firstly I need to select the weight that I think I can lift with 100% for 12 reps. This is tough as many things will make a difference to how much weight you can lift from day to day. Motivation, what you have eaten, hydration levels, warm up, how recovered your muscles are from previous workout, what you have done that day etc etc) So the chance of even us professionals getting it right is pretty low.
We may get one of the three sets to 12, sometimes even two but three in a row happens very rarely. Your muscles should be tiring, so how much rest you have will have a profound impact on how many you lift. When ever we, as trainers, lift we have a number we aim for to help us reach our goals(the power, strength and endurance figures above) but we will always lift as many as we can.
If I am aiming for 15 reps and on my first set after performing as many as I can (on 4 plates), I only manage 12 reps, then I will drop the weight slightly for the second set (3.5plates). If on the second set I do as many as I can and make it to 19 reps, then for the third set I may put the weight back up (3.75 plates). This ensures that I always lift as many as I can, and as close to my target as possible.
Next time your in the gym try doing as many as you can instead of stopping at 12 or 15 reps. Push out as many as you can. If you can do more reps than you aimed for increase the weight. If you do less reps than you aimed for then decrease the weights. Follow this principle and you always lift the right reps and the right weight.
Note: Some sessions, circuits, cardio/weights super sets, often require specific numbers of reps, 20 being the usual number given. This is for logistical reasons as much as anything else and the same principle still applies of performing as many as you can. However if working in pairs or groups this will cause problems with timings and rest and hence why the specific number of reps is stressed.
www.SCIENTIFICAMERICAN.com
Why do veins pop out when exercising, and is that good or bad?
Mark A. W. Andrews, professor of physiology at the Lake Erie College of Osteopathic Medicine, offers this answer.
Contrary to expectations, perhaps, bulging veins during exercise have nothing to do with an increase in either blood volume or pressure in these vessels. In fact, both are known to decrease during stepped-up activity, including exercise. To explain the prominence of veins during exercise, it helps to understand the vascular system and its components. Blood that circulates throughout the body is pumped from the left ventricle of the heart. It first enters into the high pressure arteries, where systolic blood pressure, the highest pressure exerted there, is recorded around 120 mmHg (millimeters of mercury), and diastolic pressure, the minimal pressure exerted in these vessels, is recorded at around 80 mmHg. (Thus, normal blood pressure is typically around 120/80 mmHg.) The blood flows into smaller and smaller branches of arteries called arterioles. As it continues along, its pressure decreases due to the resistance of the walls of the arterioles themselves. The blood then enters the capillaries--the smallest blood vessels--which provide nourishment to, and remove waste material from, active cells. There are more than one billion of these in the human body and they are extremely small and thin. The pressure exerted by the blood as it enters the capillaries is approximately 30 mmHg.
This pressure decreases even further as the blood completes its nourishment functions and then leaves the capillaries to flow back toward the heart via the smallest veins--the venules. The venules combine into larger and larger veins until they feed into the right atrium of the heart as the vena cava. By the time blood enters the largest veins, pressure exerted by the blood stream is only a few mmHg and its return to the heart is moved along more by muscle activity and breathing than its own inherent force.
When exercise begins, the heart's rate and strength of contraction increases and blood is quickly pumped into the arteries. As this is occurring, systolic blood pressure increases linearly with exercise intensity, rising to nearly 200 mmHg during high intensity aerobic exercise (and to more than 400 mmHg during weight lifting). Diastolic pressure, on the other hand, changes very little with aerobic exercise (although it rises during weight lifting). Simultaneously, the internal diameters of veins and venules narrow in a process called venoconstriction, forcing the flow of blood forward to the heart and enhancing their ability to receive blood coming from the capillaries. Overall, this process helps decrease the pressure in the venules and veins to at most about five mmHg.
Venous volume and pressure thereby decrease and are thus not the basis for the bulging. Instead, the process occurring in the capillaries as a result of the rise in arterial blood pressure during exercise causes plasma fluid otherwise resting in these tiny tributaries to be forced out through the thin vessel walls and into compartments surrounding the muscles. This process, known as filtration, causes a swelling and hardening of the muscle that is noticed during exercise. As a result of this swelling, cutaneous veins are pushed toward the skin surface, flatten to some extent, and appear to bulge. Such veins are more visible in persons with less subcutaneous fat. This bulging is neither good nor bad but simply a result of normal physiological mechanisms that result from the rise in arterial blood pressure during exertion
www.SCIENTIFICSMERICAN.com
What food should I EAT?
By personal Trainer Nick Wachter
Firstly lets talk about the foods you probably shouldnt eat. In fact lets not bother, everybody aready knows what foods are bad for them. I always perform an exercise with my clients where they have to tell me what foods are bad.... To date i have never, in the ten years ive been training people, ever had anyone who didnt know that pizza, chocolate, take aways, pop, alcohol, sweets, bisuits, crisps, cakes, deserts etc was bad for them.
Many start off with "im not too sure" or "im not very good on food" but by the time they realise theyre not going to be spoon fed the answers they always do very well.
The truth is digital television and the internet everyday we are getting told what is good and what is bad. There are a few mixed messages but in general, and with a few sources of information, there in no one in the western world who can use the excuse i didnt know what to eat.
Different Diets. Since moving to Australia everyone seems to be doing Jenny craig or a few others i had never heard of. Suprisingly theyre no different to the slimming world, weight watchers, rosemary conelly ones that are big in the UK. In general they all try to get you to eat less bad stuff and more good stuff. They have different methods of getting you there, but all aim for the same thing. A reduction of calorie by reducing fat content within your daily food intake. Some say carbs are bad other focus on fats but they all aim to reduce the overall amount and usually by cutting the bad stuff (which is full of fat)
What is the good stuff?
Vegitables, Fruits, Meats, Fish! Thats it. If we only had these in the world we would be a very healthy planet. Because these are the things that have been around for hundreds of thousands of years. Although on average we do less activity/exercise than those of times before us, it is mainly the massiv eincrease in total food consumption (total calories) that have made our waistlines expand.
Try eating for a week, only fruits vegitables and meats/fish. Have a variety and try to have a different one of each every day. Forget how much, just get thos enutrient sinto you. :)?
Diet Diary Doubles Weight Loss
Dieters who wrote down everything they ate had twice the weight loss of other people following the same diet. Karen Hopkin reports July 11, 2008
Listen to this podcast here:
[The following is an exact transcript of this podcast.]
Dear diary: Today I ate three carrot sticks while I fantasized about eating carrot cake. Alright, alright, I ate three pieces of carrot cake, and never once considered an actual carrot. How am I ever going to lose that last 10 pounds? Well, new research shows that keeping a diarya food diarycan help. According to a study published in the August issue of the American Journal of Preventive Medicine*, people who write down everything they eat each day lose twice as much as those who dont.
Nearly 1,700 people participated in the study. They were asked to follow a heart-healthy diet, full of fruits and veggies and low-fat or nonfat dairy. They attended weekly group sessions and were told to engage in moderate exercise for half-an-hour a day. After six months, nearly two-thirds of the participants had lost at least nine pounds. But the real surprise came from the food logs: those who simply kept track of what they consumed lost twice as much as those who failed to fess up. So next time youre tempted by the clarion call of the carrot cake, stop to consider how it would look in your diarynot to mention on your hips.
Karen Hopkin
www.WEBMD.com
Exercise & Osteoporosis
At any age, exercise is essential for maintaining healthy bones. If you exercised regularly as a child and young adult, you probably helped maximize your bone production, most of which occurs by age 35. If you continued to exercise into middle age and beyond, you probably helped reduce your risk of developing the bone-thinning disease osteoporosis.
But it's never too late to start a bone-healthy exercise program, even if you already have osteoporosis or are at high risk of developing osteoporosis.
Although people with osteoporosis may believe that exercise increases the risk of injury from broken bones, the truth is quite the opposite. A regular, properly designed exercise program may actually help prevent the falls and fall-related fractures that so often result in disability and premature death. That's because exercise strengthens bones and muscles, and improves balance, coordination, and flexibility, which is especially important for older adults and people who have been diagnosed with osteoporosis.
According to the National Osteoporosis Foundation, the best exercises for building and maintaining bone density are:
Weight-bearing exercise, such as walking, that makes you work against gravity while staying upright.
Muscle-strengthening exercise, such as weight lifting, that makes you work against gravity in a standing, sitting, or prone position.
Nonimpact activities such as balance, functional, and posture exercises also may benefit people with osteoporosis. Although these exercises don't build or maintain bone density, they may increase muscle strength and decrease the risk of falls and fractures.
Medical Evaluation Is Key
If you have osteoporosis or are at risk of osteoporosis, most experts believe that supervised weight-bearing exercise and strength training exercise is safe and effective. Studies of postmenopausal women report that aerobic, weight-bearing, and strength training exercise can increase bone mineral density in the spine, and that a simple walking program can increase bone mineral density in the spine and hip.
Before beginning any exercise program, it's important to undergo a thorough medical examination to determine which activities are safe for you.
There is no single exercise regimen that's best for everyone with osteoporosis. Each regimen should be specifically tailored to the individual patient based on a medical evaluation of:
fracture risk
muscle strength
range of motion
level of physical activity
fitness
gait
balance
During the evaluation, your doctor also will consider any other chronic conditions that can affect your ability to exercise, such as obesity, high blood pressure, and heart disease. If you're at risk for osteoporotic fracture, the National Osteoporosis Foundation recommends that your doctor refer you to a specially trained physical therapist for a through physical assessment and exercise prescriptions that focus on body mechanics and posture, balance, gait and transfer training, resistance weights, and progressive aerobic activities.
Weight-Bearing Exercises for Osteoporosis
If your doctor determines that it's not safe for you to perform high-impact weight-bearing exercises, he or she may recommend low-impact weight-bearing exercises that are less likely to cause fractures and also build and maintain bone density. These include:
elliptical training machines
low-impact aerobics
stair-step machines
walking (either outside or on a treadmill machine)
If you're new to exercise, or haven't exercised for awhile, you should aim to gradually increase your level of weight-bearing exercise to 30 minutes per day on most days of the week.
Programs that maintain muscular strength can slow the loss of bone mineral density associated with osteoporosis, and may help prevent fall-related fractures. Examples of muscle-strengthening exercises include functional movements such as standing and rising on your toes, lifting your own body weight, and the use of equipment such as:
elastic exercise bands
free weights
weight machines
Experts recommend performing strength-training exercises two to three days per week.
Nonimpact Activities for Osteoporosis
Certain nonimpact activities can improve your coordination, flexibility, and muscle strength and reduce your risk of falls and fractures while increasing your mobility and overall quality of life.
Balance exercises such as Tai Chi can strengthen your leg muscles, and help you stay steadier on your feet. Posture exercises can improve your carriage, reduce the "sloping" shoulders associated with osteoporosis, and decrease your risk of fractures, especially in the spine. Functional exercises can improve your ability to perform everyday activities such as getting in and out of bed and chairs, and climbing stairs.
Balance, posture, and functional exercises can be performed daily.
Nonimpact programs such as yoga and Pilates can improve strength, balance, and flexibility in people with osteoporosis. But some of the movements associated with these programs -- including forward-bending exercises -- can increase the risk of fracture. If you're interested in such programs, ask your physical therapist to tell you which movements are most likely to be beneficial or harmful.
Although exercise can benefit almost everyone with osteoporosis, it's important to remember that it's only one component of an overall treatment program. Other essential lifestyle recommendations include a diet rich in calcium and vitamin D, maintaining a normal body weight, and avoiding tobacco use and excessive alcohol consumption. You also may require osteoporosis medications to either build or maintain bone density. By working with your doctor, you can develop an osteoporosis treatment program that's right for you.
www.WEBMD.COM
What should my heart rate be?
ROUGH GUIDE
Beginners 100 – 135 bpm
Intermediates 120 – 155 bpm
Advanced 140 – 175 bpm
Personal trainers often use Heart Rate to judge how hard someone is working. We also use, the look on your face, your ability to talk, your rate of perceived exertion (RPE) (we ask you basically) how much your sweating etc etc. However many of these factors can vary, how hot it is, how positive a person is, how important the conversation is etc.
Heart rate is a great way to judge it. The best way is to wear a heart monitor belt around your chest. They cost about $25 dollars, but you can also get a watch with them for between $50-$1000 dollars. Depending on how good a watch you want. But for most of us holding the silver parts of the handles on the machines will do.
The above rough guide depends on several factors.
Time - How long are you doing the exercise for. If you doing an hour non stop session (walking x training) you are not going to work as hard as if you do 1 minute hard followed by a rest (intervals).
1 HOUR SESSION
Beginner 100 bpm
Intermediates 120 bpm
Advanced 140 bpm
1 MIN INTERVALS
Beginner 135 bpm
Intermediate 155 bpm
Advanced 175 bpm
Remember if your a beginner start of slow and gradually (over the weeks/months) increase your hr by one or two beats a week. I.e work a little tiny bit harder each time, but ensure your first 5 or 6 sessions are very indeed. At least at the beginning they will all get hard at the end.
Exceptions
The above are general guidelines however every ones max heart rate will differ. But these guidelines can still be followed for all.
ELITE ATHLETES
Lets give some examples of hr.
Bike ride last week average hr of 150bpm for 2:15mins.
Triathlon yesterday average hr of 163 bpm for 45 mins.
The fitter you are the longer you will be able to keep your hr high. So if your exeptional fit then you can work to the higher end of the scale for longer.
Dispelling the myths of "core"
By Personal Trainer NICK WACHTER
Recently i started working at one of the posh health clubs in Perth Its quite expensive and generally the members who go there are quite intelligent and hold down good jobs that involve their brains. It makes me ponder. how brainw ashed are we, even the more interlectual of us, by the medi in our society.
Let me explain. As one of the trainers, i have to take a 15 mins abs class. Apparently though it isnt abs its "letscompletely fall in line with fashion and work on our core" Since when abs become core and what the hell is core anyway and why do we all need to do it and how in gods name does it help us get a flat stomach.
Core refers to the muscles that stabalise the spine when we move. For any muscle to work and move a bone (lever) the joint has to be stable. Ie if you try to push a car while standing on ice or standing on a small float in a pool you get no friction (no stability) and instead of the car moving, you move and fall in a big mess. We used to call core "spinal stability"
Who needs to work to their cores?
New mums for sure. Abdominals become discended during pregnancy and tighten back up after. Providing you are physically active. Hard to imagine not being with a new born baby.
Those with bad backs, hips and even knee's.
All of us for injury prevention.
But none of us need it, to make our bellies flatter. As they will still have a while heap of fat on top of it. Im a big fan of injury prevention and as such all of my clients do core work. But they do core work while training, they use their core on weights exercises on heavy levels on cardio as well as some specific exercises for themselves.
Try taking away the back support for leg extension/curls, keeping your hands on your chest. The weight will feel heavier, Now your core is working.
Lift your legs on bench press. Now your core is working.
Do a 1 arm db press, now your core is working.
Intergrated core training is good. Isolated core training is for those who have injuries and specific conditions.
Want a great core workout, try a kettle bell class, Or the new ViPR classes. these are old fasjion classes that use your bodies positioning combined with the weight of the equipment to work many groups of uscles at once, including your core.
www.SCINTIFICAMERICAN.com
The fattest ape:
A evolutionary tale of human obesity
Long before I began stockpiling a rather eclectic collection of curiously homoerotic Men’s Fitness magazines in my closet as a randy teenager, decades still before the global pornification of the 21st -century Internet age, my tender childhood libido found a secret refuge amidst the colorful scenes contained in a handful of old university textbooks placed happily among my parents’ bookshelves in the family room of our home. There were of course images of famous imposing nudes made of marble and granite, and also the vibrant Romantic paintings with fully liberated genitalia proudly occupying the glossy pages of those cumbersome art history volumes common to 1960’s liberal arts colleges. And, indeed, I am forever indebted to the ancient Romans for visually educating me—a wide-eyed, insignificant little prehomosexual first-grader in a suburban cul-de-sac in 1980’s Virginia—about the idealized male form.
But it is safe to say that my very first exposure to any naked human was actually to a very different species of human altogether, when at the age of about five or six, my eyes lit upon an image—one that is seared in my memory to this day—in my father’s old anthropology textbook. It was a waxy, reconstructed display of an anatomically correct, ragamuffin group of Homo neanderthalensis people going about some daily routine at the yawning entrance to their cave, its walls dancing with the shadows from a roaring hearth inside. I don’t know if this quite qualifies me as a zoophile, since, after all, humans and Neanderthals do share an immediate common ancestor in Homo erectus (and given my geographic heritage and in the light of evolutionary genetic models of interbreeding, I could very well have some Neanderthal material floating about in my genome), but I must say, while their faces frankly left much to be desired, and personally I’ve never found prominent eyebrow ridges to be especially pretty, those other hominins did have some very fit and desirable bodies, to say the least. Comparing their ripped, muscular physiques to, say, many of those portrayed in the art history textbook, such as Peter Paul Rubens’ corpulent pastry-popping damsels, or even the most ancient goddess of fertility herself, the blubbery Venus of Willendorf (pictured above), it was the toned Neanderthals toward whom my amorous affections always returned.
And no wonder they were in such good shape. Although they were—as they are often characterized—intelligent, large-brained tool users who had mastered the use of fire and appear to have had at least a semblance of culture, Neanderthals were also advanced carnivorous predators whose diets consisted mainly of meat, fat and marrow and who devoted an extraordinary amount of their time to the relentless pursuit of large, wily game. Bone isotope analyses of Neanderthal remains reveal that their bodies were highly specialized to an intensely active lifestyle in the arctic conditions of Ice Age Europe, consuming as many as 4000 calories a day in their slaughter of meaty animals such as reindeer, bear, mammoth, bison, horses and wild cattle.
But, although they would put most modern-day bodybuilders to shame, Wright State University researcher Anna Bellisari points out in her excellent review article on the history of fatness in a 2008 issue of Obesity Reviews , this massive dietary intake, and in particular an almost exclusive, physiologically pigeonholed reliance on flesh, led eventually to the Neanderthals’ downfall. “When the European climate became even colder during the last glacial maximum,” writes Bellisari:
… metabolic demands finally outstripped the ability to supply adequate energy for maintenance and reproduction, despite their use of caves, rock shelters and fire for protection and warmth. Large game animals, the primary food sources, had become more difficult to find. Neanderthals were forced to move to southern Europe and western Asia, their final habitats before they completely disappeared.
In fact, there is even evidence that the last remaining Neanderthals in France and Spain may have become so desperate for meat that some even resorted to survival cannibalism. Cave sites in these areas have yielded Neanderthal bones with cutmarks and percussion scars similar to those found on butchered animal remains; these bones were discarded haphazardly among the heaps of random animal bones in ancient abattoirs rather than buried deliberately as they were for other individuals.
The Neanderthals had a good run, all things considered. They survived on this planet for over 250,000 years. Considering that we’ve been around ourselves as a species for only about 195,000 years, you’ve got to respect the Neanderthals’ carnivorous tenacity. And for reasons that will become apparent very soon, our own evolved feeding habits may well mean that we will actually be an even shorter-lived species. In our case, we’re our own worst enemy; but for the Neanderthals, it was indirect competition for scarce food resources with our Cro-Magnon (anatomically modern) human ancestors that seems to have put the final nail in their coffin.
We now know that modern humans and Neanderthals coexisted for at least 10,000 years—and, again, evolutionary genetics data show that we occasionally even mated with them. See, it’s not just me being titillated by depictions of naked Neanderthals; for many of you prudish readers of a certain descent, your own ancestors were just as kinky as I: Those cold-weather apes may have had brooding Neanderthal faces, after all, but their bodies were simply divine. Having said that, though, it turns out that one of the reasons interbreeding with Neanderthals was not even more prevalent than it might otherwise have been is that our Homo sapiens predecessors actually seemed to prefer their reproductive partners to be a bit on the juicier side of the scale.
Earlier I mentioned the 22,000-year-old, adipose-laden Venus of Willendorf statuette, which, since it’s discovery in 1908 in a loess deposit near a small village in Lower Austria’s Danube Valley, has been interpreted by scholars as representing the Upper Palaeolithic exaggerated ideal of female beauty, with extreme fat deposits in her breasts, buttocks and hips, precisely the areas mobilized during pregnancy and lactation. And, as University of Oxford anthropologists Stanley Ulijaszek and Hayley Lofink discuss in their 2006 piece on the biocultural history of obesity in the Annual Review of Anthropology, the closest living behavioral analogues to our early Homo sapiens ancestors, contemporary foragers in traditional societies such as those in Nauru, Samoa and Malaysia, continue to view plumpness as attractive. “Various societies across the world,” the authors also note, “practice or have practiced ritual fattening to promote fertility, marriageability and embodied social status.” One can see how powerful cultural factors are indeed only by imagining an anxious soon-to-be bride in, say, central New Jersey agreeing to be ceremonially leavened up like a fatted calf by her loving family members and adoring fiancé in preparation for the big event.
But the cultural abhorrence of fatness in modern industrial societies can also be understood in deeper evolutionary terms, since it may reflect an overcompensated aversion to a very recent adaptive problem facing a growing majority of our species. (It’s worth pointing out that there are some meaningful within-cultural differences in this area; overweight African-American women, for example, are less dissatisfied with their bodies, see themselves as healthier, more attractive generally, and as being more attractive to the opposite sex than do white women of similar weight and age.) Having some curves is one thing, amorphous obesity quite another. The cute Palaeolithic -era excess gathering coquettishly around the fertile hips of yesteryear has today morphed into a heaving, gigantic, mobility-cart-using problem signalling serious chronic disease. Obesity—which is the condition in which excess body fat has accumulated to such a degree that health and function are impaired, and which is operationally defined as having a body mass index (BMI) greater than 30 —would have been virtually unheard of among our hunter-gatherer ancestors, just as it is among modern foragers. According to Bellisari in her 2008 Obesity Reviews article:
The diet of Palaeolithic foragers was probably the most nutrient-dense and healthful in all of human history. The ‘Palaeolithic Diet’ has been reconstructed and its nutritional impact evaluated by combining archaeological data with observations of the few remaining modern foraging peoples. Daily calorie consumption was high, an average of 3000 calories per day, and meat constituted a significant 35–50% of the diet, with wild plant foods making up the remainder. Wild game contains much less saturated fat and up to five times more healthful polyunsaturated fat than meat from domestic farm animals. The Palaeolithic combination of lean meat, wild nuts, fruits and vegetables was lower in carbohydrates and higher in protein and micronutrients, including cancer-preventing antioxidants, than the modern industrial diet. It also contained less sodium, more fiber, and more of virtually every vitamin and mineral — potassium, calcium, Vitamin B, Vitamin C, iron and folate. Sugar, salt and alcohol were unknown. Skeletal remains of Upper Palaeolithic populations indicate their tall stature and generally good skeletal and dental health.
So Homo sapiens screwed the Neanderthals in more ways than one. We had a much more flexible and variable diet, and when we emigrated from Northern Africa to Europe and Asia around 100,000 years ago, we brought along with us an impressively evolved suite of anatomical, cognitive and social advantages that the Neanderthals—who’d been rigidly specialized to Ice Age conditions—just couldn’t compete with. Perhaps most important of all adaptations allowing us to edge out the last remaining Neanderthals, however, was our ancestors’ differential capacity to get fat—or at least, to store “energy reserves” in the form of adipose tissue that the body could draw from in times of scarcity and famine that came with often extreme seasonal fluctuations. Although the human foraging strategy enabled permanent settlement in nearly all of Earth’s ecological niches, food availability was massively unpredictable; it was literally a world of feast or famine, and so squirreling away energy reserves as fat deposits in our bodies supplied vital backup fuel during famine or incapacity (such as during pregnancy and the long period of dependency in young children), as well as the go-to energy source required for significant subsistence-related physical exertion.
According to Ulijaszek and Lofink, it is highly probable that natural selection operated on human phenotypes that were better able to store fat in this manner. That is to say, human fatness evolved, and it was in fact a remarkable evolutionary innovation. Compared to any other primate species, human beings have substantially greater levels of body fatness and reduced levels of muscle mass. When I was an undergraduate, I used to baby-sit a chimpanzee named Noelle, who at six months of age could easily lift herself up with one hand and had the biceps to show for it. That may sound impressive—and indeed it is in the physical fitness domain. Yet while Noelle’s chubby human counterparts lacked her muscle mass and could barely sit up at the same age, all that baby fat (enabled largely by their human mother’s own fat lower bodies) was busy giving them a cognitive advantage by providing these human infants with all that stored energy for costly brain metabolism and simultaneously reducing their energy expenditure by rendering them largely immobile. In other words, human evolution underwent a sort of trade-off of brawn for brains; and genes for fatness, especially as they are expressed during the long dependent period of human infancy when babies are undergoing rapid, radical cognitive change, played a vital role in the origins of human intelligence. Of course other species, such as those raised in captivity or domestic pets (like my gluttonous cat, Tommy), can become obese when placed in environments in which food availability is not offset by energy expenditure demands. But, strictly in terms of body fatness relative to muscle mass, our own species easily wins the crown for being the fattest ape. In fact, biologist Alister Hardy incorporated this fact into his original—now mostly defunct—“aquatic ape” hypothesis: the subcutaneous layer of fat in human bodies facilities buoyancy, whereas the muscle density of other apes leads them to sink like stones in the water.
If you’re an obese person and can trace your being significantly overweight to some combination of genetic factors—over 600 genes, markers and chromosomal regions have been associated with human obesity phenotypes using the Human Genome Obesity Map, and these heritable factors include everything from individual differences in metabolic rates to the tendency to engage in spontaneous physical activity to specific syndromes involving deficiencies of energy-regulating peptides—there’s a good chance that your genetic makeup would have given you a leg-up over your “naturally skinny” peers if only you’d been born about 10,000 years earlier. This is probably why you have these genetic contributions to your obesity today, in fact, because they helped your adipose-pocketing ancestors survive during food shortages.
It was 10,000 years ago, during the transition to the Neolithic period and, more specifically, to an agricultural lifestyle and the subsequent abandonment of foraging, that the tide began to turn and these fat-storing genes, ironically, became deadly. In the beginning, the tide turned very, very slowly. Although obesity occurred in some wealthy, high-status individuals in ancient Greece, Byzantine, Greco-Roman regions and elsewhere, until the late-19 th century, when the streamlined industrialization of food started to make basic subsistence relatively effortless for increasing numbers, farming and agriculture was a laborious business with energy expenditure demands rivalling—and in some cases, exceeding—those of foraging. As Bellisari points out:
Plant cultivation and animal husbandry required rigorous and constant, year-round labor. Energy expenditures of early farmers are estimated to be as high as those of modern farmers in non-industrial societies. Crops sometimes failed and animals died prematurely or did not reproduce as expected. Pests and natural disasters destroyed stored food surpluses. Food shortages and starvation were not uncommon. Domestic animals transmitted bacteria and parasites to humans in densely populated farming villages and towns, causing epidemics of infectious diseases not experienced by nomadic foragers.
So even during these difficult early agricultural times, fat-storing phenotypes would have been evolutionarily advantageous, since food availability was still highly unstable and starvation a very real threat. Farming may have offered convenience and was logical, given the growing impracticalities of foraging, the dwindling populations of wild game and human population growth with its increasingly large and complex societies, but this convenience of domesticating edible species came, initially, at a rather heavy cost. “Wherever farming replaced foraging,” writes Bellisari:
… there was a general decline in human health. Unequivocal signs of nutritional deficiencies, growth disturbances and increasing disease burdens are evident in the skeletal remains of farmers, from the earliest beginnings of agriculture to historic times. The most detailed studies of health decline come from early agricultural communities in North America, where skeletal lesions document iron deficiency anaemia and tubercular bone infections in populations that adopted maize as the primary food crop. Chronic protein-energy malnutrition, and a high prevalence of dental caries, abscesses and tooth loss were related to high-carbohydrate diets. Average adult stature was significantly lower, and life expectancy decreased relative to preceding foraging populations.
Although for different reasons than ever before, then, these harsh, early farming conditions were not exactly favorable for promoting obesity either. Most scholars believe that morbid obesity was relatively unheard of until we began industrializing the food industry and specialized production became privatized. In fact, Ulijaszek and Lofink argue that it was actually only about 60 years ago—after the dust settled from WWII and with the advent of slick advertising, cheap transport and prepackaged convenience foods—that those old, previously adaptive fat genotypes that evolved during the Palaeolithic -era materialized into the crippling, plus-sized problem that we have today. This is such a tiny sliver of time in our species’ evolutionary history that it can hardly be expressed mathematically, but needless to say, it is not enough time for natural selection to counteract what was, for so long before, clearly adaptive. (That’s not to say that natural selection isn’t operating against obesity today; again, the growing negative cultural attitudes toward fatness may be helping to drive this selection alongside the actual detriments to genetic fitness directly caused by obesity.)
Today, by the sheer sweat of our forefathers’ brows—or rather, their healthily metabolized fat—we have achieved unprecedented food security for the couch potato masses. This was a hard-won achievement, certainly, and has allowed our species to divert its attention from a mere subsistence-based lifestyle to other creative pursuits. But today’s industrialized nations are “obesogenic environments,” a term coined by University of Auckland medical researcher Boyd Swinburn and his colleagues in 1999, and which refers to human environments in which the physical, economic, social and cultural atmosphere involves “energy intake in excess of expenditure.” In other words, obesogenic environments are those in which food consumption, in combination with the increasingly sedentary lifestyle accommodated by food security, leads to such an accumulation of body fat that it compromises our physical health.
It’s astounding really. Consider what you’ve had to eat so far today. Don’t leave anything out. Now picture yourself trying to explain the nature of that food to an exhausted Palaeolithic forager straining to understand —while sitting cross-legged on the floor of some transposed temporal dimension in your living room and, yes, you’ve mastered some obscure Palaeolithic tongue, play along now— the concept of, say, a potato chip. To name all of the delicious sundries we ingested today, all the concocted chemical supernovas happening in our slobbering mouths, is simply obscene. How fortunate we are to live in a time of such abundance. And how unfortunate, too.
–he says while licking the chocolate from his fingers and finishing off his can of Red Bull.
A Healthy Brain Needs a Healthy Heart
Could exercising regularly and not smoking help to delay dementia?
By Christine Gorman |November 30, 2010 |
When the National Institutes of Health convened a panel of independent experts this past April on how to prevent Alzheimer’s disease, the conclusions were pretty grim. The panel determined that “no evidence of even moderate scientific quality” links anything—from herbal or nutritional supplements to prescription medications to social, economic or environmental conditions—with the slightest decrease in the risk of developing Alzheimer’s. Furthermore, the committee argued, there is little credible evidence that you can do anything to delay the kinds of memory problems that are often associated with aging. The researchers’ conclusions made headlines around the world and struck a blow at the many purveyors of “brain boosters,” “memory enhancers” and “cognitive-training software” that advertise their wares on the Web and on television. One of the panel experts later told reporters in a conference call that the group wanted to “dissuade folks from spending extraordinary amounts of money on stuff that doesn’t work.”
But did the panel overstate its case? Some memory and cognition researchers privately grumbled that the conclusions were too negative—particularly with respect to the potential benefits of not smoking, tr
eating high blood pressure and engaging in physical activity. In late September the British Journal of Sports Medicine published a few of these criticisms. As a longtime science journalist, I suspected that this is the kind of instructive controversy—with top-level people taking opposing positions—that often occurs at the leading edge of research. As I spoke with various researchers, I realized that the disagreements signaled newly emerging views of how the brain ages. Investigators are exploring whether they need to look beyond the brain to the heart to understand what happens to nerve cells over the course of decades. In the process, they are uncovering new roles for the cardiovascular system, including ones that go beyond supplying the brain with plenty of oxygen-rich blood. The findings could suggest useful avenues for delaying dementia or less severe memory problems.
Dementia, of course, is a complex biological phenomenon. Although Alzheimer’s is the most common cause of dementia in older adults, it is not the only cause. Other conditions can contribute to dementia as well, says Eric B. Larson, executive director of the Group Health Research Institute in Seattle. For example, physicians have long known that suffering a stroke, in which blood flow to the brain has been interrupted by a clot or a hemorrhage, can lead to dementia. But research over the past few years has documented the importance of very tiny strokes—strokes so small they can be detected only under a microscope after death—as another possible cause for dementia. Studies at autopsy of people who had dementia have detected many of these so-called microvascular infarcts either by themselves or along with the plaques and tangles more typical of Alzheimer’s in the brains of people with dementia. These findings suggest that most dementias, even those caused by Alzheimer’s, are triggered by multiple pathological processes and will require more than one treatment.
Proving that cardiovascular treatment is one of those approaches will take some doing. Just because microinfarcts may make dementia worse does not mean that preventing them will delay the brain’s overall deterioration. Maybe severe dementia makes people more vulnerable to microinfarcts. And just because better control of high blood pressure and increased physical activity seem to decrease a person’s risk of stroke, that does not necessarily mean they are less likely to suffer microinfarcts. Correlation, after all, does not necessarily imply causation. That scientific truism was the problem that kept bothering the panel of outside experts put together by the NIH. Thus, the expert panel concluded, with one exception, that “all existing evidence suggests that antihypertensive treatment results in no cognitive benefit.” Data showing the benefits of boosting physical activity in folks with confirmed memory problems were “preliminary.”
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The controversy boils down to semantics, says Martha L. Daviglus, chair of the consensus panel and a preventive cardiology researcher at Northwestern University’s School of Medicine. “Obviously, smoking and hypertension are risk factors for cardiovascular disease,” she says. “And they may turn out to be risk factors for Alzheimer’s disease as well,” she says. But after reviewing all the evidence, Daviglus and her fellow panelists concluded that it “failed to provide convincing evidence” of the link, whereas other researchers see “some evidence” of a link.
