Monday, January 20, 2014

Rant: That Economics Professor/Obama/Socialism Meme

This "economics professor" meme's been going around for at least a year now and several times I've vowed to take it on but never got around to it. I saw it again recently and, even though I'm supposed to be working on my syllabus, I can't take it any more. For those of you who haven't seen it before, I've pasted it in its most recent incarnation below. My comments follow.

An economics professor at a local college made a statement that he had never failed a single student before, but had recently failed an entire class. That class had insisted that Obama’s socialism worked and that no one would be poor and no one would be rich, a great equalizer.
The professor then said, “OK, we will have an experiment in this class on Obama’s plan”.. All grades will be averaged and everyone will receive the same grade so no one will fail and no one will receive an A…. (substituting grades for dollars – something closer to home and more readily understood by all).
After the first test, the grades were averaged and everyone got a B. The students who studied hard were upset and the students who studied little were happy. As the second test rolled around, the students who studied little had studied even less and the ones who studied hard decided they wanted a free ride too so they studied little.
The second test average was a D! No one was happy. When the 3rd test rolled around, the average was an F.  As the tests proceeded, the scores never increased as bickering, blame and name-calling all resulted in hard feelings and no one would study for the benefit of anyone else.
To their great surprise, ALL FAILED and the professor told them that socialism would also ultimately fail because when the reward is great, the effort to succeed is great, but when government takes all the reward away, no one will try or want to succeed. Could not be any simpler than that.
These are possibly the 5 best sentences you’ll ever read on this experiment:
  1. You cannot legislate the poor into prosperity by legislating the wealthy out of prosperity.
  2. What one person receives without working for, another person must work for without receiving.
  3. The government cannot give to anybody anything that the government does not first take from somebody else.
  4. You cannot multiply wealth by dividing it!.
  5. When half of the people get the idea that they do not have to work because the other half is going to take care of them, and when the other half gets the idea that it does no good to work because somebody else is going to get what they work for, that is the beginning of the end of any nation.
What I am reading now is liberals, progressives or those that dismiss the STORY because it’s a scenario and not real. They can’t cope with the real truth that you can’t move poor people into prosperity by legislation from Washington, DC.  Government doesn’t have the authority to take from Citizen A and give to Citizen B to make things even.
I'm not even going to bother addressing the "Obama as a socialist" because only the most misinformed of the misinformed could possibly call Obama a socialist.  And besides, it's not really relevant to the core issue, which is an ostensible critique of "socialism".  Yes, I'm using scare quotes, because the allegory creates such a strawman of socialism, it is recognizable only as a cold war era parody. 

Anyway, there are way too many problems with this meme to discuss in just one post, so I'll limit myself to discussing 2 major problems.  

False Assumption:  Theory of Desert
Some of the main problems with this "experiment" are the false assumptions typical of adolescent libertarians.  

Check out this passage and see if you can find the false assumption(s):

 After the first test, the grades were averaged and everyone got a B. The students who studied hard were upset and the students who studied little were happy. As the second test rolled around, the students who studied little had studied even less and the ones who studied hard decided they wanted a free ride too so they studied little.

The assumptions here has to do with a notion of desert that is tied strictly to effort.  More effort=you deserve a higher grade, and the converse is also assumed, if you got a poor grade, it's because you didn't try very hard: you always get what you deserve.  Although utterly simplistic, in itself this notion has intuitive pull, but a fleeting moments reflection will suggest that this is NOT how grades are distributed.  As anyone who has struggled through a math class can tell you, if grades reflected effort, they wouldn't have received a C but a A; and I'm sure we've all known someone who, thanks to natural talent, sailed through a math or chemistry class with little or no effort, only to receive an A.  As someone who has worked as a tutor and a teacher, I can assure you, grades and effort have a mild correlation but that is it. 
There are many more important variables that determine a student's grade such as (a) native intelligence, (b) parental, family, and peer support, (c) whether they have to work a part-time job to pay for school, (d) the quality of their previous educational institutions (e) nutrition during childhood development.  In fact, THE NUMBER ONE PREDICTOR OF ACADEMIC SUCCESS IS A STUDENT'S SOCIO-ECONOMIC BACKGROUND.  There are decades of literature supporting this conclusion--and the effect is regardless of gender, geography, and culture.  

Now lets complete the analogy with distribution of wealth.  This fantasy notion that in our economic system wealth is distributed according to effort would be laughable if it weren't the source of so much pernicious vilifying of the poor and self-congratulation by the rich.  Consider for a moment the typical minimum wage earner who works 2 full-time jobs just to pay his/her bills and put money aside to send their child to college.  What about a teacher who works in the inner city and runs the unpaid after-school extra-curricular activities? Are we seriously to believe that this person doesn't work as hard as a banker, someone who plays the stock market, or someone who inherited or married into wealth simply because of the amount of wealth they have?

This idiocy also ignores the fact that, next to the UK, the US has the lowest rate of social mobility in the industrialized world.  Do you think this is because poor people have a lazy gene that gets passed from generation to generation or might it be that those that come from wealth have the economic and social support networks to acquire the skills and relationships necessary to achieve and maintain their socio-economic status?  E.g., a family that has the wealth to send kids to university without incurring student debt, to be able to focus 100% on school and networking because they can avoid having to work a p/t job while in school, etc...  A family that lives in an area with good elementary and high schools so the child has the skills to be successful when they do go to university?  A family that lets the child avoid student loans, so when they're done with school you aren't saddled with 10s of thousands of dollars of debt as you begin your post-school life.  A family where there isn't regular violence so the student can concentrate on school work without fear of abuse?  

When I tutored low-income high-school kids, some of the kids couldn't go home for fear of violence. The police were regularly called to the house to break of fights.  Imagine trying to study in that atmosphere.  Sorry kid.  You chose the wrong parents and you're just not trying hard enough. You deserve whatever happens to you.  (And please don't give me that bullshit story about the one kid who overcame blah blah blah.  Yeah, he/she was an outlier, therefore everyone can do it.  That's science.)

In an economy where a good education is a strongly correlated to economic success, unequal access to good educational facilities at an early age is going to initiate a sequence of events which will have multiplier effect on unequal access to economic opportunity.  The supporting literature is there for anyone who cares to relinquish their fantasy that "hard work" is all it takes to make it.  

“At virtually every level, education in America tends to perpetuate rather than compensate for existing inequalities. The reasons are threefold. First, the K through 12education system is simply not very strong and thus is not an effective way to break the link between parental background and a child’s eventual success. … Second, because K–12 education is financed largely at the state and local level, resources devoted to education are closely linked with where people live and with the property wealth of their neighbors. For this and other reasons, poor children tend to go to poor schools and more advantaged children to good schools. … Finally, access both to a quality preschool experience and to higher education continues to depend quite directly on family resources.”  2006 Policy Brief of the Brookings Institution, Isabel Sawhill (2006:3)

Lets look at some numbers, shall we? In the US, only 8% of men that grew up in a family in the bottom 20% made it to the top 20% (Therefore, 92% of the bottom 20% don't work as hard as those in the top 20%).  42% of men born into the bottom 20% stay there.  65% born in the bottom 20% stay in the bottom 40%.  Should we infer from this that 65% of offspring in the bottom 20% are just lazy?  They obviously deserve to be poor.  They just don't work hard.  It's got nothing to do with the huge advantages that come with growing up in the top 40% and the major disadvantages of growing up poor and having to compete with resource-abundant competitors.  And, certainly, whatever jobs the poor do, they don't work very hard...that's why they deserve to be poor.

Lets look at the flip side:  62% of Americans (male and female) born into the top 20% stay in the top 40%.  I'm sure each and everyone of them worked hard (at least 2x as hard as any poor person works) for that economic status and didn't get any help, didn't take advantage of their parents' valuable social network for jobs, didn't inherit or receive any of their parents' wealth to start a business, didn't marry a rich spouse, etc...  They didn't have any advantages over their poor counterparts and so they deserve the extra wealth because it is purely a reflection of their individual effort which began on a level playing field--the very same one the poor kids started on.  If only those poor kids had worked as hard as the rich kids, they could be rich too.  But no.  They just decided to be lazy and that's why they deserve to be poor.

I could rant for days on the myth that wealth and academic performance is a measure effort rather than natural talents, parental support, socio-economic class, social capital, home environment, health, peer group, neighborhood, access to quality primary and secondary education, and dumb luck but I shall stop here. 

There's normative issue that relates to the relationship between desert and effort but it intersects with the next section so I shall address below:

False Assumption:  Motives 
There are a lot of false assumptions about student (and by extension, worker) motive and covering all of them would take too much time, so I'll cover just one:  The professor's "experiment" (and by extension, the analogy) imposes a false view of what motivates action in a "socialist" system (or even in this one).  Also, the experiment presumes a hyper-individualist mindset which is what occurs in a system where people aren't frequently incentivized to help others (i.e., a capitalist one).  In such a system, all action is selfishly directed since helping others comes at a cost.  In a socialist system, community has value and so the action calculus isn't simply a matter of considering what is best for one's self but must also take into account the effect on the welfare of the community.  

The libertarian might reply that "waaaaaaaaaaaaahhhh! but human nature is selfish and people won't realistically help others."  This is complete bullshit.  First of all, there's no such thing as human nature as it is popularly conceived. If there is any intrinsic component to human nature it is that we thrive in strong caring communities and wither in hyper-individualized ones.  Our behavior is a response to whatever environment we are in.  If we create/live in an environment in which there is a great cost to altruistic behavior, then we can expect people not to engage in such behaviors.  It is a matter of what resources are scarce, what types of behaviors are incentivized, sense of group-belonging, and how resources are allocated.  It is also a matter of value.

In a socialist society, the flourishing of the community has value independent of the individual.  This is unlike in a libertarian conception where everything centers on the individual to the total destruction of community (check out any number of studies on the modern demise of American sense of neighborhood and community).

So, if we are to construct a real socialist "experiment" in the classroom, we have to set up the incentives such as we'd find in a socialist society.  We'd also have to reconsider what the goal is.  As (ill)conceived by the professor, the goals and rewards are individual grades.  We'd need to change this to reflect a better conception of a socialist classroom.  The goal should be the community's (i.e., the class') knowledge of economics, not individual grades.  

Now we have to consider how to incentivize behavior that will be conducive to this end:  Consider perhaps the professor rewarding the students with natural aptitude for helping the students that are struggling.  Anyone who has ever taught anything knows that the best way to learn something is to teach someone else.  Students help one another for the benefit of the community goal and both groups benefit in so doing.  It's not just a matter of sending students home with their books, each one hoping the other will study.  It's a matter of working together to achieve a shared goal.

Stop and think for a moment if you were in such a class and you were a struggling student.  A group of students who excel in the class spend time with you every week to help you learn the material.  What is the social effect of this show of support, care, and solidarity from your peers?  Might this incentivize you to work hard and perform to the best of your ability?  Might you feel compelled to not let the group down?  This would be a better reflection of a socialist classroom.  

The objective of the class is to get everyone to excel at the material.  The students are motivated not by mere letter grades but by a desire to learn the information (whoa! what a concept!).  Ostensibly, they wouldn't be in an economics class if they didn't want to study economics.  There are literally hundreds of other classes they could have taken, many of them easier, so the idea that students are solely motivated by individual grades is spurious.   
If you want to reject this socialist class model as a pipe dream, know that there are schools all over the world (including the US) that operate with this model that have excellent learning outcomes comparable to the best prep schools.

Lets once again complete the analogy with work.  The implicit assumption is that, just like students with grades, workers only work to get money.  Money is obviously an important reason for which people work (especially at the low end of the pay scale where individual's life circumstances are usually such were they just need a job--any job--and often don't have the luxury to find one they genuinely like) but it is not the only reason people work.  Without listing them, I'm sure you can think of jobs that pay more than your own that you wouldn't do.  If pay were the only thing people cared about, you wouldn't be able to think of higher paying jobs that you wouldn't do.

Lets talk about redistribution of resources.  The assumption is that high wage earners don't see any value in having part of their wages redistributed to (in theory) improve their community and so, would cease to "work so hard".  While it wouldn't surprise me if there were a minority who felt this way, I doubt they are the majority.  Most people recognize the value of social programs.  

This brings me to another false assumption about the proportion of  tax dollars that go to welfare programs.  Between 9 and 12 cents/dollar of your total tax bill goes to welfare.  So, if you paid 10 000.00 in tax, between 900.00 and 1200.00 of that went to welfare payments.  Basically, just under 100/month.  

Is it really plausible that someone making over 100 000 in wages (unlikely, since most people in this income bracket don't derive all their income from wages, but lower-taxed capital gains etc...) is going to stop working because they have to pay $100-150 a month to welfare?  Are we really supposed to believe this crap?

I could create an entire blog devoted to all the problems there are with this meme  Anyway, the few I've mentioned should be a start.  If I get bored one day, I'll address the 5 bullet points at the end of the meme. 

Concession:  The libertarian/conservative does have some legitimate concerns when it comes to the possibility that certain types of welfare programs can create learned helplessness (i.e., welfare culture).  There is empirical support for this but by and large, the proportion of people who abuse welfare programs is dwarfed by the number of people that don't (depending on the program, there is between 3 and 10% fraud).  Add to this that the proportion of the population actually on welfare is very small (4%)--especially if you consider current economic conditions.

Even if certain welfare programs do promote learned helplessness, this is not an argument against welfare programs, but an argument against certain program designs.  There are many ways to address chronic poverty through welfare policy.  The main predictors of how long someone will stay on welfare are their job skills and education.  If these two variables aren't simultaneously addressed while assistance is given, the likelihood of the recipient coming off welfare goes up dramatically.  To assume they stay on welfare because they are lazy is to ignore these statistics.  Without job skills and education how can we expect such individuals to enter the job market and become self-sufficient?

Thursday, January 16, 2014

Critical Thinking: The Secret Technique Professors Don't Want You to Know!

Critical thinking sounds fancy but it's something most of us do everyday.  In fact, most of us are quite good at it...so long as we are properly motivated.   Unfortunately, we absolutely suck when the motivation is wrong--and I'm not talking about money.

What do I mean by all this talk of correct and incorrect motivation?  What I mean is that, when someone is trying to argue against our own cherished position and beliefs, most of us are very good at pointing out the problems with our opponent's arguments.  We are primarily motivated to want to be 'right' and to protect our most cherished beliefs from criticism and so, in such cases, our critical thinking skills are generally quite good.

We are absolutely horrible critical thinkers when an argument or evidence favors our existing cherished beliefs. Why? Because, as I said before, we are primarily motivated to be right and to protect our beliefs, thus, we will usually uncritically accept any argument or evidence that supports our position.  Any argument or evidence that serves our purpose is, ipso facto, good.  Consider:  When was the last time you were critical of an argument or evidence that supported your own position on an issue?

What's the moral of the story here?  Most of us already have a intuitive grasp of critical thinking, what messes it up is our motivation to be right and to protect pre-existing conclusions.  So, if we want to be good critical thinkers, we need to manipulate our motives; or at the very least be aware of their capacity for distortion.

What is Critical Thinking?
To understand what good critical thinking is, it helps to contrast it with poor critical thinking.  The way most people reason is that they look at the conclusion of an argument or the conclusion some evidence implies and assess whether that conclusion agrees with their pre-existing beliefs and positions.  If the argument/evidence agrees with or supports their pre-existing position then the argument/evidence is considered good.  If the converse is true, then the argument/evidence is considered defective.   To summarize the problem: Most people focus on whether they agree or disagree with a conclusion rather than on the quality of the argument/evidence.  This approach is not good critical thinking.

In critical thinking we don't care two hoots whether we agree or disagree with the conclusion:  all we are interested in is whether the argument or the evidence is good support the conclusion.  Critical thinking is mainly about two things:  (a)  standards of evidence (i.e., what constitutes good evidence?) and the logical relationship and relevance of premises of arguments to their respective conclusions (i.e., does the conclusion follow from the premises?).  That's all.  The end.  Good night.  (For convenience, I'll refer to both of these aspects as "quality of evidence/arguments").

The Secret that Professors Don't Want You to Know:
Good critical thinking is all about focusing on the quality of the arguments/evidence relative to conclusions but unfortunately our brains are hardwired to look at the conclusions relative to our pre-existing beliefs. Because we should really focus on the quality of arguments/evidence, we need a trick to overcome the tendency to focus on the conclusion.

The Ol' Switcheroo Version 1:  (a) If an argument or evidence supports your position, ask yourself if you'd find the argument/evidence compelling if the same quality of evidence/justification supported the opposite conclusion.  (b) If an argument/evidence is against your current position, ask yourself if you'd find the quality of evidence/justification compelling if it supported your position.

For example (a):  Suppose you think vaccines cause autism and to support your conclusion you cite the fact that your nephew has autism and he was vaccinated; therefore, vaccines cause autism.  To apply critical thinking special secret #1 we construct a similar argument but for the opposite conclusion:  E.g., I have a nephew and he was vaccinated and isn't autistic; therefore, vaccines don't cause autism.

If your original position was that vaccines cause autism, would this second argument cause you to change your position?  Nope, I doubt it would, and for good reason: a single case doesn't tell us anything about causal relations.  Notice that applying secret thinking sauce #1 allows us to focus on the quality on the evidence rather than on whether we like the conclusion. So, if the second argument fails as good support for the conclusion, so does the first, even though it supports your position.  Boom! goes the dynamite.

Lets try another example (b):  Suppose you are an anthropogenic climate change denier.  Someone argues against your cherished beliefs by saying 97% of climate scientists agree that human activity is responsible for climate change.  Your natural reaction is to discount this as an insignificant argument because it contradicts your pre-existing position.  Now apply critical thinking secret sauce #1 and ask yourself: If 97% of climate change scientists denied that human activity has any effect on the climate, would you consider this as good support for your position?

Lets try a moral example:  In the "homosexuality is bad vs homosexuality isn't bad" debate both sides often make appeals to what is or isn't natural behavior as justification for their position.  Lets apply critical thinking secret sauce to both sides to show why both justifications are weak: 

"Homosexuality is morally wrong because it's unnatural."  The justification here is that moral wrongness is a function of whether something is unnatural.    Now, applying the ol' switcheroo, we ask the person who takes this position: Supposing homosexuality were natural, would you then agree that homosexuality is morally permissible? They will likely answer, "no" thereby indicating that naturalness is a poor justification for moral permissibility. 

But it isn't just evangelical moralists that are using poor justifications for their claim.  Lets apply the same test to those who argue that homosexuality is morally permissible because it is natural for a certain percentage of the population to be gay (usually some sort of genetic argument is given).  Lets try applying the ol' switcheroo:  

Suppose scientists discover that there is no "gay gene" and that homosexual behavior is purely a matter of some combination of socialization and personal choice.  If this were the case, would proponents of the argument then say "welp, I guess homosexuality is morally wrong after all"?  Probably not.  And the reason is that whether a behavior is natural or not tells us nothing about that behaviors moral status.  

Whatever one's opinion on the moral status of homosexuality, the ol' switcheroo shows us that both positions cannot be supported through appeals to "naturalness".  That is, the quality of that particular justification is weak regardless of which conclusion we are sympathetic to.

The Ol' Switcheroo Version 2:  Sometimes issues are such that the simple switcheroo won't work too well in helping to focus our minds on the quality of arguments/evidence; so, we need a variation of the switcheroo to deal with those situations.  Here it is: (a*) If an argument/evidence supports your pre-existing position, ask yourself if a similar argument or evidence would be convincing to you in an different issue to which you are opposed.  (b*)  If an argument/evidence is against your cherished beliefs, ask yourself if a similar argument would be convincing in an issue where you are a proponent.  

Basically, in this version we're trying to generalize the principle that is being used to justify a conclusion then apply it to other cases to see if the principle is being applied consistently or (as is often the case) the principle is being used when it supports a conclusion we like but is being denied when it supports a conclusion we dislike.

Example (a*):  Suppose you think homeopathy works and that you are generally skeptical of conventional medicine.  To support homeopathy you cite a particular scientific study shows that 70% of subjects no longer had condition X after homeopathic treatment.  The study has a sample size of 10 and there's no control group.  Ask yourself, would such a study convince you that a new conventional medication was effective for condition X?

Of course not.  A sample size of ten is way too small to conclude anything of consequence and the lack of a control group makes a study, especially of this size, essentially worthless.  If the evidence in the second case wouldn't be good support the conclusion, then the same applies to the first case.  Critical thinking secret v.2 allows you to see why the evidence you've provided isn't good.

Example (b*)  Suppose again your pre-existing position is that global climate change is not caused by human activity.  Someone points out that 97% of climate scientists think the opposite: that global climate change is attributable to human activity.  Now apply critical thinking secret sauce v.2:  pick an issue where you have a pro position or even one where you don't have position: suppose it's that it's consistent with the 2nd amendment that people should be able to own guns free of restrictions.  Ask yourself: if 97% of all constitutional experts agreed that unrestricted gun ownership is consistent with the 2nd amendment, would you consider this to be a good reason in favor of your position?  If yes, then you have to also allow that it's a good reason in the first case too.

Wednesday, January 8, 2014

Annual Fitness Post: Injury Prevention with Breathing Technique

Over the last several years I've pretty much covered every meaningful piece of advice on how to get in shape.  

This year I'm going to cover how to prevent injury.  I'd say that this is probably the most difficult lesson for former competitive athletes to learn because the most significant way to prevent injury involves not exerting yourself 100% when you aren't feeling 100%...Probably common sense for most people.  Anyhow, lets git our lern on.

Broken Record:
Before I begin, I just want to repeat the most fundamental lessons for success in fitness:
(a) The work out/physical activity you actually enjoy and will do regularly is better than the perfect physical activity that you hate and will quit after a few weeks.

(b)  If your primary goal is weight-loss, calories in vs calories out is your first guiding principle of how to eat.  Obviously, don't be dumbass about it and eat small meals of nutritionless food, but by and large, calories in must be fewer than calories out or you simply won't lose weight.  That's science!

(c)  Medium-high intensity activities generally yield better fitness and health results than low intensity activities.

(d)  Leverage the effects of social pressure:  If you aren't naturally motivated to exercise, you'll probably have a better chance of sticking to an activity if it's a social activity.  Also, publicly announcing your goals and/or having a friend check up periodically on your progress increases your likelihood of success.

(e)  Resistance exercises:  (i)  Over the last decade, there's been a growing body of quality evidence showing that resistance/strength programs outcompete endurance exercises in terms of combating the effects of aging.  (ii)  If you want to incorporate strength exercises (i.e., weight training) and you've never really done it before, please, please, please hire a professional personal trainer to get you started. Make sure that the person actually weight trains themselves (and has done so for at least 5 years) and isn't some yoga or aerobics instructor who took a weekend certification course.  A simple heuristic to find out if they are knowledgeable about weighlifting is to ask them: "Do you even?".  If they reply with "do I even what?" or "I don't understand the question" find another trainer.

(f)  Don't waste your money on supplements.  99% of them don't have any good evidence to support their efficacy.  If you insist on supplements, the only ones I'd recommend are protein powder and creatine.  Possibly pre-workout powder if you need an energy boost but a coffee does the same thing, has the same active ingredient, and is cheaper.

I Enjoy Preventing Injury Because:
Now that we've got that out of the way, lets get down to the important matter of preventing injury.  At the very real risk of stating the obvious, it's important to avoid injury because:
(a)  injuries hurt and make me cry

(b)  injuries keep you away from your activity of choice thereby causing you to lose (i) your precious gains and (ii) your momentum which in turn sends you back to you pre-activity sedentary state from which you must one more time begin the difficult task of overcoming the inertia of inactivity.

(c)  injuries cause further injuries.  Often in protecting your injured body part, you'll compensate in a way that causes you to injure another body part.

By far, one of the most common area that gets injured is your back.  So, if there's a way to minimize back injury, maybe we should check it aus...

Correct Breathing
Ok, if you aren't going to include weight lifting into your fitness plan, then this section isn't too relevant to your needs.  But it may be, so read it anyway.  I spent time writing the damn thing!

Fact: 99% of fitness trainers teach incorrect breathing technique for weightlifting (source: Ami's Journal of Test Tubes, Beakers, and Scientifical Facts).  Let me qualify that: it depends on the type of lift (and some will say the amount of weight in relation to your max).  But lets not get caught up in distinctions, this is a fitness post!  Everything I teach you will make you lose 20 lbs in 2 weeks and cure cancer!

The valsalva maneuver.   That's what I'm talkin' 'bout!  Instead of 'splaining it, I'm going to illustrate. Nay! You're going to illustrate it! Good teachers explain, great teachers make you figure it out your own damn self (or something like that).

Drop something on the floor right now.  Slowly bend over and reach down to pick it up. Wait! Stop! While doing this, I want you to focus on the sensation in your lower back. When your torso gets to about perpendicular with the floor, I want you to exhale.  Now, pick up the dropped object and return to your erect position (heh heh heh....he said "erect position").

Now I want you to try to duplicate the exact same motion but this time before initiating your movement inhale deeply and hold your breath.  Without releasing the air in your belly and chest, bend over and pick up the fallen object and focus on how it feels in your lower back. Don't release your breath until you are almost fully erect again (heh heh heh...he said "fully erect").

What were the results?  In the second case, your lower back should have felt more support and less strain that in the first.

Here's another experiment to illustrate the principle:   Hold yourself in push-up/plank position. Now exhale all the air from your lungs.  What happens to the stability of your core?  Does it sag?

Repeat but this time, while in push up position, inhale and fill yourself with air and hold it. What happens to the stability of your core?  Is it more stable?

Doing this carefully controlled experiment should reveal to you the one secret the fitness industry doesn't want you to know! You should only breath in, and never exhale!  This will make you appear more buff and saving you 1000s of dollars on expensive steroids supplements!

Ok, I kid.  Here's the real lesson: When you are doing strength exercises that require a stable core (mainly: squat, deadlift, bench press, military press, shoulder press, any olympic and power lift), before you initiate the movement, you should breath IN and fill your belly and torso with air and HOLD your breath during the main exertion of force, releasing it only once the most difficult part of the movement has been completed (you can let a little air out through pursed lips during exertion).

To summarize the technique (video below):
1. Using your diaphragm (not your chest), inhale deeply before the non-exertion phase of the movement.   E.g., in a squat it will be when you are standing upright before you go down; with bench press and military press it will be when the bar is overhead before you lower it.

2.  Hold your breath and tighten your abs as though someone is going to punch you in the stomach as you lower the bar.  This stabilizes your core.

3.  When you exert force to begin the upward movement, keep holding your breath for the first part of the movement (the most difficult part) and then, near the top of the movement, release your breath.  Note: some people say to release a little bit of air through pursed lips during the main exertion.  Figure out what works for you.

4. Repeat.

Here are a couple of videos illustrating how to use this breathing technique (called the valsalva maneuver in fancy talk) with the most common lifts:

Nerd Note: There are actually 2 types of valsalva maneuvers: (a) the most common one is the one you do during the descent of an airplane when you plug your nose and try to equalize your sinus and ear pressure; (b) the weightlifting one is called the gloittial version because you close your windpipe (with your gloittus) to create pressure in your abdominal and thoracic cavities.

Some good general points, despite his committing the naturalistic fallacy:

The Squat:

The Deadlift: 

The Down-Side and Fine-Print:
First of all, at your next training session where you're doing squats, your zumba weightlifting instructor will tell you to exhale when you exert force in the lift.  Then you're going to say, "but I read on the internets that you should use the glottial valsalva maneuver during the most difficult part of the lift."  At this point you should tell them where on the internets you got the advice.  If they don't immediately recant their position and acknowledge their ignorance in the face of my superior epistemic position, then the correct response is to say "do you even lift?" and walk away.

Apart from conflicts with your pillates weightlifting instructor there are a couple of other risks you should be aware of when using the valsalva maneuver.  While the risks might lead some uninformed fools to conclude that the valsalva maneuver shouldn't ever be used, these nervous nellies aren't taking into account several important distinctions.  Before I address the distinctions, here's a quick list of some of the possible risks incurred by using the valsalva maneuver: 

1.  The valsalva maneuver creates A LOT of internal pressure.  If you have any kind of abdominal hernia you'll probably want to avoid it.  You'll want to avoid it if you really have to go to the bathroom too...

2.  The valsalva maneuver reduces blood-flow to the brain so there's a risk of feinting if you're prone to it.  Also, the reduced blood-flow to your brain means you should avoid attempting complex cognitive operations like doing calculus while holding your breath and lifting heavy weights. 

3. The valsalva maneuver can cause valsalva retinopathy which appears as preretinal hemorrhage (bleeding in front of the retina).  I'm not sure if this is a downside cuz it's a cool story to tell your bros. 

4.  Your blood pressure goes up and your heart rate goes down because of the increased internal pressure.  If you have a history of heart conditions, you might want to avoid doing it.  Consult a qualified homeopath first...I kid:  talk to a real freakin' doctor, damn it! 

The Fine-Print:
Are you scurd? Sounds like a lot of risk just to prevent back injuries and to get gains. Actually, it's not.  It's about as risky as pushing hard while on the toilet when you're constipated (where you've been using the valsalva maneuver for years!). The possibility of negative effects occurs only if you're lifting really really heavy weight which, lets be honest, most of you aren't (do you even?).  So long as you're lifting below 350lbs, there's no real risk.  The greater risk is to your back.

One more thing to note is that if you decide to use the valsalva maneuver for heavy weight (as you should), you should avoid doing sets of more than 5 or 6 reps.  Holding and releasing your breath under heavy load for a standard set of 10 reps increases the likelihood of lightheadedness (and the other problems ) although it's still negligible.  If you aren't lifting heavy, then it's not going to be the end of the world if you don't use the valsalva maneuver but I'd recommend it anyway if you want to protect your back. 

Finally, you don't need to use the valsalva maneuver for every type of exercise.  It's primarily used for heavy compound lifts such as squat, deadlift, military press, bench press, and any olympic lift.  For those movements you're much better off using it than not. For other lifts, especially isolation exercises, you're fine using the breathing technique your aerobics instructor taught you.

In sum, the valsalva movement is an effective way to prevent injury to your (2nd) most vulnerable region--your spine.  

Last Word on Injury Prevention
I've got two words for you:  You have to warm up or you will increase your chances of injury.  Did I go over the word limit?  Oops.  

Good warm-up plan:  
1.  Do 10-15 min at med intensity on one of the cardio machines.  If you're training upper-body that day, use the elliptical.     

2.  Start with compound exercises (i.e., exercises that use more than one muscle group) that focus on a large muscle group (chest, back, legs, shoulders).  Finish your workout with isolation exercises (i.e., exercises that isolate one muscle or aspect of a muscle).  For example, if I'm working chesticles I don't start with flys or cable cross-overs because these movements isolate the chest and don't involve any other muscle groups.  I start with bench press because this uses my triceptors, shoulders, and chest.  Similarly, if you're doing legs, don't start with hamstring curls or leg extensions.  You should start with squats or dead lifts or possibly leg press, all of which use a combination of muscles in your legs as well as your torso.

3.  Do as many warm up sets as you need, gradually adding weight, before starting your working sets.  I usually do 3 warm up sets for my first exercise--sometimes fewer, sometimes more depending on how I feel.

4.  If after 3 or 4 warm up sets, your normal working weight feels heavy, back down.  Your body isn't "feeling it" today which means there's a good chance you'll injure yourself if you push it.  Do your working sets with a slightly lighter weight than you'd normally use.

5.  Once you've done your first major compound exercise, you probably will only need 1 warm up set for your next exercise.

Now stop making excuses and go to the gym.