Wednesday 26 September 2012

Anaerobic exercise - Wikipedia

Anaerobic exercise - Wikipedia


  (Redirected from Anaerobic threshold)

Anaerobic exercise is exercise intense enough to trigger anaerobic metabolism. It is used by athletes in non-endurance sports to promote strength, speed and power and by body builders to build muscle mass. Muscle energy systems trained using anaerobic exercise develop differently compared to aerobic exercise, leading to greater performance in short duration, high intensity activities, which last from mere seconds up to about 2 minutes.[1][2] Any activity lasting longer than about two minutes has a large aerobic metabolic component.[citation needed]

Anaerobic metabolism

Anaerobic metabolism, or anaerobic energy expenditure, is a natural part of whole-body metabolic energy expenditure.[3] Fast twitch muscle (as compared to slow twitch muscle) operates using anaerobic metabolic systems, such that any recruitment of fast twitch muscle fibers leads to increased anaerobic energy expenditure. Intense exercise lasting upwards of about four minutes (e.g., a mile race) may still have a considerable anaerobic energy expenditure component. Anaerobic energy expenditure is difficult to accurately quantify, although several reasonable methods to estimate the anaerobic component to exercise are available.[2][4] [5]

In contrast, aerobic exercise includes lower intensity activities performed for longer periods of time. Activities such as walking, running (including the training known as an interval workout), swimming, and cycling require a great deal of oxygen to generate the energy needed for prolonged exercise (i.e., aerobic energy expenditure). In sports which require repeated short bursts of exercise however, the anaerobic system enables muscles to recover for the next burst. Therefore training for many sports demands that both energy producing systems be developed.

There are two types of anaerobic energy systems: 1) the high energy phosphates, ATP adenosine triphosphate and CP creatine phosphate and, 2) anaerobic glycolysis. The high energy phosphates are stored in very limited quantities within muscle cells. Anaerobic glycolysis exclusively uses glucose (and glycogen) as a fuel in the absence of oxygen or more specifically, when ATP is needed at rates that exceed those provided by aerobic metabolism; the consequence of rapid glucose breakdown is the formation of lactic acid (more appropriately, lactate at biological pH levels). Physical activities that last up to about thirty seconds rely primarily on the former, ATP-PC phosphagen, system. Beyond this time both aerobic and anaerobic glycolytic metabolic systems begin to predominate. The by-product of anaerobic glycolysis, lactate, has traditionally thought to be detrimental to muscle function. However, this appears likely only when lactate levels are very high. Elevated lactate levels are only one of many changes that occur within and around muscle cells during intense exercise that can lead to fatigue. Fatigue, that is muscular failure, is a complex subject. Elevated muscle and blood lactate concentrations are a natural consequence of any physical exertion. The effectiveness of anaerobic activity can be improved through training.[1] [6]

References

  1. ^ a b Anaerobic training
  2. ^ a b Medbo, JI; Mohn, Tabata, Bahr, Vaage, Sejersted (January 1988). "Anaerobic capacity determined by maximal accumulated O2 deficit". Journal of Applied Physiology 64 (1): 50–60. Retrieved 14 May 2011.
  3. ^ Scott, Christopher B (June 2005). "Contribution of anaerobic energy expenditure to whole body thermogenesis". Nutrition & Metabolism. 14 2. doi:10.1186/1743-7075-2-14. Retrieved 14 May 2011.
  4. ^ Di Prompero, PE; G. Ferretti (Dec. 1). "The energetics of anaerobic muscle metabolism". Respiration Physiology 118 (2-3): 103–115.
  5. ^ Scott, Christopher B (2008). A Primer for the Exercise and Nutrition Sciences: Thermodynamics, Bioenergetics, Metabolism. Humana Press. pp. 166. ISBN 978-1-60327-382-4.
  6. ^ McMahon, Thomas A (1984). Muscles, Reflexes, and Locomotion. Princeton University Press. pp. 37–51. ISBN 0-691-02376-X.

See also

there is no finish line...enjoy the ride...: May 2011

there is no finish line...enjoy the ride...: May 2011


It may seem like common sense that if you don't use your muscles, they'll eventually atrophy, yet so many people fail to apply this information in their daily lives.  The older you get, the faster your muscles will atrophy if you're not regularly engaging in the appropriate exercise. Additionally, older muscles do not respond well to sudden or intense bouts of exercise, so the key to avoiding sarcopenia (age-related muscle loss) is to challenge your muscles with intense exercise on a regular basis throughout your life—and it's never too late to start.

Growing Old
GROWING OLD IS NOT FOR SISSIES

Is Strength Training Sufficient to Prevent Age-Related Muscle Loss?
Sarcopenia, or age-related muscle loss, begins affecting people in their mid 20’s, initially at a rate of 1% loss of muscle mass per year, with accelerated rates as age advances and the muscle mass is replaced with fat.
Causes include:
  • Hormonal changes
  • Sedentary lifestyle
  • Free Radicals
  • Oxidative Stress damage
  • Inflammation
  • Insulin resistance
  • Acidic Diet
It's a major challenge that many go through, especially the elderly, and as I just mentioned, regular exercise is essential to counteract this muscle loss. However, it's important to realize that simply lifting weights will not result in gaining muscle mass. Additionally, if you are involved in prolonged exercises like aerobics or running, you will not have the hormonal influences to build muscle either, even if you lift weights. It's important to understand that in order to effectively build and maintain muscle you need to incorporate short bursts of high intensity interval exercises that elevates your heart rate above your Anaerobic Threshold

This kind of exercise allows your body to produce human growth hormone (HGH) naturally. Yea, the same stuff that athletes take to cheat in their sport, however they take it in the form of a synthetic drug.  HGH is also known as "the fitness hormone," and is essential for healthy aging, fitness, and yes, muscle building.

Additionally, you need to supply your muscles with the appropriate fuel at the appropriate time to provide them with the proper building blocks to produce new muscle tissue.

Mickeys Daily Dose » Growing old

Growing Old Is Not For Sissies

May 9th, 2009
growingold2

As I near my 50th birthday I’m a little freaked out.  All my life I have always looked and felt 10 to 15 years younger than I really am.  Turns out this lucky gene that I have had all my life resonates with my siblings as well.  I recently connected with 2 brothers and a sister who I have never met, and they too are much younger looking than they are.

But what about this pending milestone in front of me?  In just 5 more months I will hit the big FIVE OH.  It really sucks.  Perhaps I dwell too much on it and its only going to have negative reaction to negative thoughts.

What does turning 50 mean?  I’m not sure but I can share with you some definite signs that I have noticed that are associated with me getting older.

(a). The condition of my yard has never been more important to me.  Now I’m the guy that stares at his lawn admiring it, comparing it to the neighbors, and I cant wait to mow it.
(b). I now use the hand rails to steady myself when stepping on to an esculator.
(c). I have not moved over to the right lane and slowed it down to 55 yet.  If ever the day comes I look in my rear view mirror and I see a line of cars impatiently trying to get around me, I’ll know its over.
(c). Just putting my socks on in the morning seems like I need a game-plan before trying to put them on.   I hear my thoughts in my head saying, “okay now, easy does it.. lets not pop a tendon first thing in the morning”.

So in the midst of my fear of becoming 50 I have begun to fight back.  I’m back in the gym and I’m jogging again.  I have seen some good results and I will continue to fight to get back in shape.  I have set a goal for my 50th birthday that I will be in better shape than I ever have been in my life so I have something about turning 50 to look forward to.

I found this wonderful picture you see posted above.  What an inspiration.  The old face with the buff body.  That’s just a great picture.   The caption means alot too.  Perhaps I should take heed and stop whining… because

Growing Old Is Not For Sissies

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Sunday 23 September 2012

Your Scientific Reasoning Is More Flawed Than You Think: Scientific American

Your Scientific Reasoning Is More Flawed Than You Think: Scientific American


New concepts don’t replace incorrect ones: they just learn to live together

In one sense, science educators have it easy. The things they describe are so intrinsically odd and interesting — invisible fields, molecular machines, principles explaining the unity of life and origins of the cosmos — that much of the pedagogical attention-getting is built right in.  Where they have it tough, though, is in having to combat an especially resilient form of higher ed’s nemesis: the aptly named (if irredeemably clichéd) ‘preconceived idea.’ Worse than simple ignorance, naïve ideas about science lead people to make bad decisions with confidence. And in a world where many high-stakes issues fundamentally boil down to science, this is clearly a problem.

Naturally, the solution to the problem lies in good schooling — emptying minds of their youthful hunches and intuitions about how the world works, and repopulating them with sound scientific principles that have been repeatedly tested and verified. Wipe out the old operating system, and install the new. According to a recent paper by Andrew Shtulman and Joshua Valcarcel, however, we may not be able to replace old ideas with new ones so cleanly. Although science as a field discards theories that are wrong or lacking, Shtulman and Valcarcel’s work suggests that individuals —even scientifically literate ones — tend to hang on to their early, unschooled, and often wrong theories about the natural world. Even long after we learn that these intuitions have no scientific support, they can still subtly persist and influence our thought process. Like old habits, old concepts seem to die hard.

Testing for the persistence of old concepts can’t be done directly. Instead, one has to set up a situation in which old concepts, if present, measurably interfere with mental performance. To do this, Shtulman and Valcarcel designed a task that tested how quickly and accurately subjects verified short scientific statements (for example: “air is composed of matter.”). In a clever twist, the authors interleaved two kinds of statements — “consistent” ones that had the same truth-value under a naive theory and a proper scientific theory, and “inconsistent” ones. For example, the statement “air is composed of matter”  is inconsistent: it’s false under a naive theory (air just seems like empty space, right?), but is scientifically true. By contrast, the statement “people turn food into energy” is consistent: anyone who’s ever eaten a meal knows it’s true, and science affirms this by filling in the details about digestion, respiration and metabolism.

Shtulman and Valcarcel tested 150 college students on a battery of 200 such statements that included an equal and random mix of consistent and inconsistent statements from several domains, including astronomy, evolution, physiology, genetics, waves, and others. The scientists measured participants’ response speed and accuracy, and looked for systematic differences in how consistent vs. inconsistent statements were evaluated.

If scientific concepts, once learned, are fully internalized and don’t conflict with our earlier naive concepts, one would expect consistent and inconsistent statements to be processed similarly. On the other hand, if naive concepts are never fully supplanted, and are quietly threaded into our thought process, it should take take longer to evaluate inconsistent statements. In other words, it should take a bit of extra mental work (and time) to go against the grain of a naive theory we once held.

This is exactly what Shtulman and Valcarcel found. While there was some variability between the different domains tested, inconsistent statements took almost a half second longer to verify, on average. Granted, there’s a significant wrinkle in interpreting this result. Specifically, it may simply be the case that scientific concepts that conflict with naive intuition are simply learned more tenuously than concepts that are consistent with our intuition. Under this view, differences in response times aren’t necessarily evidence of ongoing inner conflict between old and new concepts in our brains — it’s just a matter of some concepts being more accessible than others, depending on how well they were learned.


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  1. 1. RSchmidt 12:38 PM 8/21/12
    Yet we have many that not only continue with the Old OS but install in their children a bronze age OS. I have been talking about the ALL curriculum for years. Instead of the 3Rs, reading, righting and 'rithmatic you have Arithmetic, Literacy and Logic. The other subjects, excluding physical education, are there to apply the knowledge gained by these core subject. With the addition of logic, less emphasis is placed on teaching "facts" and more is placed on reasoning and the ability to evaluate data sources. The best thing you can do for your child's future is to teach them the benefits of delayed gratification, I believe the second best is to teach them critical thought. One of the worst thing to teach them is that faith is a valid replacement for knowledge, and that faith is more important that evidence. Reply | Report Abuse | Link to this



  2. 2. RogerPink 01:10 PM 8/21/12
    I'm more concerned with unsupported superstitions that scientists, in spite of all evidence to the contrary, believe. For instance "The simplest answer is most likely the correct one" is almost never correct and requires herculean feats of rationalization to defend, yet this misunderstanding of Occam's Razor (not even close to what his intent was when he wrote it) pervades science and our society as a whole. These are the real dangers to science, not that we have to think an extra second in order figure out the correct answer to distinguish between colloquial and scientific definitions. Reply | Report Abuse | Link to this



  3. 3. Derick in TO in reply to RSchmidt 01:23 PM 8/21/12
    If you teach your children critical thinking, and teach them to apply it to everything, you don't need to teach them that faith is not a valid replacement for knowledge - it's self-evident to anyone who has ever thought critically about their own beliefs. Of course, critical thinking among the general population is anathema to religious and political leaders. It's so much harder to control a populace that questions what it sees and hears and challenges established ideas. Hence the lack of logic and critical thinking in school curricula, and the inclusion of (un)intelligent design and "teaching the controversy". Reply | Report Abuse | Link to this



  4. 4. WRQ9 01:37 PM 8/21/12
    You ( the SI editing staff ) continue to refer to some people as "you". When I read that, it refers to me, and anybody else reading it. It gets annoying at times. I am fully aware that even the best scientific reasoning can be flawed, and the flaws are therefore generally of greater scope than imagined. I can anticipate weaknesses in any of my notions and make allowances regarding language and so forth. Like a good engineer, I imagine what total breakdown could look like in every phase of an operation. Still in all, I do not assume imperfection in others as an exorcise in respect. I assume adults have performed to their peak capacity and any failure would be directly related to the complexity of the task and/or their ability to perform it. Assumed perfection is an unavoidable flaw in reasoning, but without it no reasoning is possible. Without evidence to the contrary, many arguments, however ridiculous in hindsight are daily tried in trepidation. Many humans will retry pet ideas well beyond the point of reason fearing the alternative, this is a form of psychosis, with the exception of legal circles. An open mind respects all attempts at reasoning. Religious people are granted by the constitution, the right to assume in a benign fashion certain unprovable concepts. Science does not allow this argument, but many scientists share dual loyalties. In effect much scientific knowledge became possible because of biblical teachings. Multiple interpretations of phenomena are not always contentious. Any good scientist must be comfortable with the circumstance of many possibilities in order to progress without the stigma of prejudice. It is good exorcise to imagine the possibility of these " unprovable concepts " if just to " cleanse the palette " for new endeavors. Reply | Report Abuse | Link to this



  5. 5. lucaspa in reply to RogerPink 01:52 PM 8/21/12
    I applaud you for knowing that "The simplest explanation is most likely the correct one" is not Ockham's Razor nor correct. It actually derives from Newton. But it is not a danger to science, because scientists don't use it in theory evaluation. It comes up in apologetics, usually atheist apologetics. What Ockham meant was not to add hypotheses to descriptions of phenomenon. His example, from his time, was "objects move because of an impetus". Ockham argued that movement was change in space over time, so all you needed to say was "objects move". That "because of an impetus" was a hypothesis that was not necessary to explain the phenomena. To Derrick: not all religious leaders or politicians deride reason. To say that they all do is to violate reason and critical thinking. Nor is faith necessarily an absence of evidence or reason. It can be, but often is not. Faith is belief in the absence of PROOF. We all believe things we cannot scientifically demonstrate. That does not mean we lack evidence or reason. For instance, the idea that democracy is a good form of government is not scientific nor "proven" by scientific evidence. Yet it does have evidence and reasons behind it. "It is important to recognize that not all "facts" are susceptible to scientific investigation, simply because some observations and experiences are entirely personal. I cannot prove that someone loves his or her child. The emotions that any individual claims to have are not susceptible to scientific documentation, because they cannot be independently verified by other observers. In other words, science seeks to explain only objective knowledge, knowledge that can be acquired independently by different investigators if they follow a prescribed course of observation or experiment. Many human experiences and concerns are not objective, and so do not fall within the realms of science." Douglas Futuyma, Science on Trial, the Case for Evolution, 1995, p 167. My children have faith that I love them. That faith is based upon evidence. But it's not science and it's not "proof". Millions of people have evidence for the existence of deity. It's faith, but not without evidence or reason. Reply | Report Abuse | Link to this



  6. 6. lawman108 02:14 PM 8/21/12
    I wonder what the researchers would have seen had they done brain scans as people answered the questions. Just speculating, maybe the pre-conceived notions that people grow up with correspond to different parts of the brain. So an answer that is consistent doesn't need to be checked, but one that is inconsistent has somehow be "tagged" so that the answer gets shunted off to a different part of the brain for consideration. Reply | Report Abuse | Link to this



  7. 7. Will_in_BC 03:34 PM 8/21/12
    I am not sure I would read too much into the longer time it took people with a good science background to respond to the inconsistent statements. A simple explanation would be that they are trained to look for subtleties and not accept the obvious. For example when I looked at the statement about air and matter I stopped to think of the various definitions of matter and which one might best apply. I think it's a good think that trained minds stop and ponder. Reply | Report Abuse | Link to this



  8. 8. FloriodaJ782 in reply to lucaspa 04:36 PM 8/21/12
    "For instance, the idea that democracy is a good form of government is not scientific nor "proven" by scientific evidence. Yet it does have evidence and reasons behind it." Democracy is not, necessarily a good form of government, nor does it have evidence behind it. Historically, democracies have been short-lived. We have only been a democracy since we legislated universal suffrage. It's true that we are betting our lives on it, but I don't think most of us are comfortable making that bet; we just don't seem to have much choice. As to "reasons behind ..." your belief that democracy is good, that's demonstrably wrong. We already see evidence of the idea that 50% can get what they want by making the other 50% pay for it, is alive and growing. Reply | Report Abuse | Link to this



  9. 9. tharriss in reply to lucaspa 05:10 PM 8/21/12
    "My children have faith that I love them. That faith is based upon evidence. But it's not science and it's not "proof". Millions of people have evidence for the existence of deity. It's faith, but not without evidence or reason." Whatever this evidence based faith tells your children and whatever this "evidence" is for existence of a deity, it is not a process well recommended for making good decisions or finding the actual truth. Children have faith Santa will leave presents under the tree for them, and evidence backs them up on it. The fact is that faith easily misleads people, even if they use some facts to rationalize their faith. If people want to take a statue that cries blood as "evidence" their faith is valid, and don't bother to look at the rusty plumbing in the ceiling above the statue, it says a lot about the value of their faith in reaching a true conclusion, but very little about the actual existence of a deity. A bit of science would go a long way into clearing up such delusions, but hey, by your stated standards, better to declare areas that are unprovable by science and just romanticize faith (backed up by "evidence") as holding the key.... what sillyness. "We all believe things we cannot scientifically demonstrate. That does not mean we lack evidence or reason. " Perhaps you are right that the one thing doesn't necessarily directly mean the other, but it does demonstrate a willingness to believe things that actually may not be true. Just because we all do it, doesn't mean it is a good way to reach a good conclusion. The beauty of the scientific method is that the process gets around our natural inclination to just believe all sorts of silly things, whether the evidence in front of our eyes seems to back it up or not, and instead makes us go through a strict process that strips away our biases and brings us ever closer to knowing what is actually happening around us. It isn't a perfect process, and usually takes time and many iterations to get past our built in preconceptions and misconceptions and human failings, but it is the best tool ever devised for eventually getting at the truth of things.... and I imagine before very much longer, will even have a scientifically verifiable way of scanning your brain and actually proving you love your kids.... although I agree most kids won't be much interested in such proof of something that seems obvious to them.... but it isn't the obvious nature of it (that you describe as faith) that makes it true... plenty of obvious seeming things actually aren't true. Reply | Report Abuse | Link to this



  10. 10. jgrosay 05:14 PM 8/21/12
    Yeah, it seems that Abrahan Maslow was the first in pointing that any new knowledge is put on the basis of the previously existent info on the field the subject has, be it a conjecture, a prejudice, or anything lacking an experimental basis. This would be one of the reasons learning things for an examination by reviewing old multiple choice questions on the subject is very dangerous: your mind records at the same level, and associated with the question, all the possible answers offered, and when in an actual situation, it will present to your conscience at similar levels of certainty the false and the right answers, in real life decision making this can lead to dangerous mistakes hard to notice until you're confronted with its consequences. Reply | Report Abuse | Link to this



Exercise: Is Less Better Than More? | Perfect Health Diet

Exercise: Is Less Better Than More? | Perfect Health Diet

New York Times column, “For Weight Loss, Less Exercise May Be More,” got some attention this week. It was based on a recent study of the effects of exercise on weight loss.
The Danish study [1] found that exercise is helpful for weight loss – but only the first 30 minutes of light exercise per day. Additional exercise had no effect on body weight – in fact it even seemed to diminish weight loss. Those who jogged for 60 minutes a day lost five pounds, those who jogged for 30 minutes lost seven.

The subjects wore activity tracking devices – Actigraph GT1-M devices, which are an older model of these and similar to a Fitbit – which produced a surprising result. Those who exercised 30 minutes a day were seemingly energized by their exercise, as they became more active in their daily lives – more likely to take the stairs, for instance. Those who exercised 60 minutes a day, on the other hand, seemed to be worn down by their exercise, and became less active in daily life.

It seems that 30 minutes of exercise improved health but 60 minutes of exercise may have diminished well-being. When it comes to exercise, perhaps, less is more.

A Well-Supported Result

While the Danish study [1] was novel in looking at how weight loss and non-exercise activity respond to exercise, it is not the first study to show that light activity may be healthier than intense activity.

In the new Scribner edition of our book, we greatly expand the part which discusses how to optimize immunity and heal or prevent disease. The new edition discusses exercise. We found a number of recent studies showing that light daily activity is as good or better than intense activity for health:
  • A study of American runners found that those who ran between 1 and 20 miles per week at a jogger’s pace of 10 or 11 minutes per mile reduced their risk of dying as much as those who ran more than 20 miles a week or who ran faster. [2]
  • Another Danish study reported that Danes who exercised two or three times per week for a total of one to two and a half hours reduced mortality by 44% and extended their lifespans by 6.2 years for men and 5.6 years for women. Those who exercised either more or less had less benefit. [3]
  • A study of 416,175 Taiwanese adults found that an hour and a half of moderate exercise per week (13 minutes per day) reduced mortality by 14% and extended lifespan by 3 years. An additional 15 minutes per day reduced mortality by only another 4%. Benefits peaked at 50 minutes of exercise per day. [4]
These are intriguing results. What’s more intriguing is that it doesn’t seem to matter how fit the exerciser is. People gain substantial health benefits from light exercise, even if the activity never makes them fit.

An Evolutionary Argument for Not Over-Exercising

Thanks to Stephan Guyenet, we’ve been talking a lot about the reward system of the human brain. It evolved in order to make us want to do healthy things, like braving the stings of angry bees to get honey from hives concealed high in trees.

David recently linked to an interesting post suggesting that our Paleolithic ancestors may have done a lot of honey gathering, which reminds me of this movie about the Hadza and their honey seeking:



Why did we develop an attractive taste for sugar, and why does the brain reward us for carb consumption? Presumably because the Paleolithic diet was too low in carbs for optimal health, and evolution wanted to encourage Paleolithic hunter-gatherers to gather more honey.

But, however valuable carbs are, it’s not clear that they are as valuable as the extra six years of life we obtain from light daily exercise. Yet there’s no innate reward for exercise. Many people are quite content to live their whole lives as couch potatoes.

Why didn’t evolution reward exercise, if it is as valuable as carbs? Probably because Paleolithic humans almost invariably got more exercise than they needed. Perhaps our brain evolved to prevent our ancestors from over-exercising, and now our brain unfortunately rewards us for over-resting!

Conclusion

It looks like exercise is healthful, but most or all of the benefits come from a relatively small amount – the first 30 minutes per day.

Doing the research for the new edition of our book has led me to revise my ideas of why exercise is beneficial, and how we should exercise to optimize health. In my next post, I’ll discuss why I think light exercise is most healthful, the tension between healthfulness and fitness, what I think a health-oriented exercise program should look like, and how my personal exercise activity has changed.

References

[1] Rosenkilde M et al. Body fat loss and compensatory mechanisms in response to different doses of aerobic exercise–a randomized controlled trial in overweight sedentary males. Am J Physiol Regul Integr Comp Physiol. 2012 Sep;303(6):R571-9. http://pmid.us/22855277.
[2] Gretchen Reynolds, “Moderation as the Sweet Spot for Exercise,” New York Times, June 6, 2012, http://well.blogs.nytimes.com/2012/06/06/moderation-as-the-sweet-spot-for-exercise/.

[3] European Society of Cardiology (ESC) (2012, May 3). Regular jogging shows dramatic increase in life expectancy. ScienceDaily. http://www.sciencedaily.com/releases/2012/05/120503104327.htm.

[4] Wen CP et al.  Minimum amount of physical activity for reduced mortality and extended life expectancy: a prospective cohort study. Lancet. 2011 Oct 1;378(9798):1244-53. http://pmid.us/21846575.

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13 Comments.

  1. Interesting post. I disagree, however, with your statement that there’s no innate reward for exercise. Exercise releases endorphins and other hormones, and has been found to be more effective in fighting depression than anti-depressant medicines. I think being a couch potato isn’t natural, but happens because people enjoy the quasi-meditative state of watching TV or surfing the web.
    • I guess in light of the study, it may work both ways. The body releases endorphins and gets healthier in response to moderate exercise but discourages more than that.
    • Hi David,
      Well, now that’s an interesting question. Endorphins are one of the circadian immune molecules we want to promote by exercising. Their presence reflects improved health, and cause it.
      It definitely feels better when we become healthier through exercise, and so many people learn from experience that it’s a good idea to exercise, and come to want to do it.
      But for most sedentary people, there’s no desire in advance of exercise to go do it; and there’s no great pleasure in the first day of exercise. As I understand it, it’s prospective wanting (motivating action) and concurrent liking (rewarding it) that the innate reward system of the brain generates. And those cues seem to be lacking.
      Best, Paul
  2. Interesting. This has certainly been my experience.
    I used to go through 3-5 months bouts of over-exercising in my attempt to manage my weight. The only other time (before Paleo/PHD) that I successfully lost a substantial amount of weight was a few years ago at which time I severely restricted calories and exercised 1-2 hours most days of the week for a 2-3 month period. T’wasn’t healthy, t’was miserable, it ended quickly, and I gained all the weight back and more.
    Last fall before learning about Paleo/PHD/etc, I spent two months meticulously counting/limiting calories and doing long cardio sessions 5-6 days a week. After two months the scale hadn’t budged.
    Since starting Paleo/PHD in January I have lost 60 lbs and put on a bunch of muscle with ease. I loosely follow Mark Sisson’s fitness rx – I lift heavy things (mostly myself) once or twice a week, I do a full on sprint every week or so, and I do plenty of enjoyable walking, biking, and playing as I am able.
    I definitely prefer smart, manageable, and cheap exercise over what I used to think I needed
  3. If there is no innate reward for exercise, there is still what Nietzsche called the “will to power” which, in its purest form, impels animals to exert themselves in acts that have no survival value and to enjoy themselves.
    Perhaps we didn’t need innate rewards when exercise helped us get food, a mate, status, territory etc. Athletes and other performers still get those rewards.
  4. I suspect that in an individual that is very healthy both mentally and physically, that person enjoys a bit of exercise and as others have mentioned, exercise releases endorphins and is well known to elevate mood. It’s just that now, most of us eat toxic foods from birth (cheerios are typically a baby’s first solid food!!!) and many of us live isolated noncommunal lives far different from what we evolved for.
  5. It may be worth disentangling intensity and volume. Though you say that moderate activity may be better than intense activity, all the evidence cited apart from the words “…or who ran faster” seem to be concerned with volume. It may be that the best sort of exercise is infrequent short bursts at high intensity, rather than longer at moderate intensity.
    • Hi David,
      Yes, that’s an important point. Intensity is a totally different variable than volume and its health effects have to be studied independently.
      Yes, there does seem to be a lot of evidence in favor of HIIT. However, the ability to increase intensity is correlated with health, so we have to be careful in analyzing studies.
  6. I didn’t watch that video the first time through – really fascinating stuff!
  7. I love having you back blogging. Interesting view on the benefits of exercise. You seem to be able look at these things from a new perspective.
    A personal experience:
    The last couple of months I have been doning crossfit style exercise. Lately I have been pondering if I was generally feeling a litle bit better when I was doing more leangains style training.
    What I still really like about crossfit is the community and the focus on learning new movements and improving mobility and not only focusing on gaining muscle.
    Can’t wait for the new book!
  8. Good vacation to you two!
    Exercise: a very complex subject indeed. Based on a recent study, maybe we should not encourage sick people to exercise (at least not more than brisk walks) but try to get healthy first. I think Table 1 is visually very revealing (and disturbing):
    Adverse Metabolic Response to Regular Exercise: Is It a Rare or Common Occurrence?
    http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3364277/
    • Hi Mario,
      Yes, I think exercise intensity and volume need to be scaled with health. Exercise should be refreshing, not stressful. For unhealthy people that means a brisk walk may be the most they should do.
  9. This is all very interesting and consistent with my own experience. I definitely feel that for general health and well being a moderate amount of light exercise is the best route. Looking forward to upcoming posts!

Monday 3 September 2012

Plyometrics - The Definition of Plyometrics

Plyometrics - The Definition of Plyometrics


By , About.com Guide
Updated October 06, 2011

About.com Health's Disease and Condition content is reviewed by our Medical Review Board
Froggy jumps for cardio 

Definition: Plyometrics is a type of training involving jumping, bounding and other high impact exercises that focus on maximizing the stretch reflex of the muscles. The purpose? To teach the muscles to produce maximum force faster, which enhances performance for athletes and exercisers alike. 
 
This stretch reflex happens when you jump, one reason we often refer to plyometrics as jump training. For example, if you jump up onto a box or step and then jump down, the quads stretch as your knees bend and then quickly contract again with the next jump. It's the prestretch of the first jump that enhances the second jump.

While plyometric training is something athletes use for training, the average exerciser can reap the benefits as well in the form of more power, more strength, more endurance and burning more calories.

There are some downsides to this type of training. It's easy to injure yourself with all that jumping, especially when you're jumping down from a high platform or step. Each time you land, your joints sustain about seven times more force than your body weight, so it's important to carefully consider the types of exercises you're doing and to ease into this type of training. A personal trainer or coach is a great resource for helping you set up a plyometric training program that fits your fitness level and goals.

Examples of Plyometric Exercises
More about plyometric training.
Source:
American Council on Exercise. ACE Personal Trainer Manual, 3rd Edition. San Diego: American Council on Exercise, 2003.

Not a bad effort - 12 week BODY TRANSFORMATION



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Published on Apr 3, 2012 by