Lab Time

Image courtesy of facebook.com

A concept that is discussed in RTS is, if you are a trainer, using your personal workout time as lab time to experiment with all of the different variables that comprise exercise.  Personally, I hadn't done much of this up until the past four weeks or so, opting instead to carry on with the programs I was writing for myself in order to improve my bench, squat, and deadlift and to just get physically stronger.

Funny enough, nobody was paying me to help them increase their bench, squat, or deadlift and maybe one of my clients truly cared about getting significantly stronger.  All of my clients, however, were coming to me because they enjoyed the way their body felt while they worked out with me thanks to the experiences I was able to create with exercise.  At least that's what I was telling myself.

The thing was, I was starting to get frustrated with myself and my inability to really create these experiences with a purpose.  I could break down the magnitude profile of a machine or exercise with little difficulty.  I could tell you what tissue was being challenged and where the approximate resultant was that was being created when I would apply more than one force to a point.

In other words, I could see the whole and break it down to the pieces.  I was struggling with the inverse, though--knowing what specific piece I wanted and creating an exercise for it--until I actually started using my own workout time as lab time.

There's nothing wrong with how I was training before, but if wanted to actually understand what I was doing and how to create it from scratch, I needed to experience it first-hand.  So that's what I've been doing for roughly the past month.  I practice figuring out different ways to challenge, for example, my elbow flexors at different points in the range, intentionally increasing the torque production demand of my tissue at some points in the range and decreasing it at others by manipulating moment arms and force angles.  I experiment with different things to focus on during the reps as well as use different tempos and use different tools to manipulate the resistance.

The result of all this has been a significant improvement in my ability to actually construct exercises as well as create an experience for my client.  Furthermore, it has forced me to think more creatively when it comes to designing exercises, which, when applied appropriately, has improved client experience.

If you don't already, I highly recommend substituting at least one of your regular workouts each week for lab time.  Do the things you have your clients do.  Create the awesome experience for yourself that you are trying to create for them.  Don't be the proverbial skinny chef of personal training!

How much time do you spend each week getting better at creating exercise experiences?

Your body.  Your training.

Want to use this arti­cle in your blog, newslet­ter, or other plat­form?  You can, but be sure to include all of the bio­graph­i­cal infor­ma­tion found in the yel­low box below!

Moment Arms

Image courtesy of chegg.com

**While all of this information can be found throughout various books and other texts, my experiences with the information have all come through different RTS lectures, study groups, workshops, courses, and discussions.  It is because of these experiences that I am able to write this post, in addition to many of my past and future posts.**

In Monday's post I wrote about the importance of seeing moment arms as they relate to joints and tissue when discussing joint motion during exercise, but I never actually defined what a moment arm is.  So, today I will give you a very brief overview and introduction to moment arms.

Image courtesy of http://en.wikipedia.org/

A moment arm is defined as the shortest distance from the axis of motion to the line of force that is perpendicular to the line of force and runs through the axis.  It is the measure of a force's ability to produce rotation of a lever around an axis, i.e. the greater or longer the moment arm the greater the force's ability to rotate a lever around an axis.

If we are going to divulge into moment arms then I should also explain what a line of force is.  A line of force is 1) a line, that is 2) created by a force (internal--mainly muscles, although other tissues can/may play a role; external--machines, free weights, tubes, bands, etc).  Remember, a line is infinitely long and goes in both directions, meaning the line of force created by gravity goes both up and down even though the vector will only go straight down.

One of the main reasons for knowing the length of a moment arm is to be able to calculate torque, which equals the force times the length of the moment arm an is a measure of rotational force.  This would be considered the resistance for that weight in that one position.  Once the weight starts to move you need to not only recalculate any changes in the length of the moment arm but also take into consideration any changes in the force, as well, which equals mass times acceleration.  That is beyond the scope of this post, though.

So, when looking at moment arms in relation to joints in the body you need to find the axis of the joint in the desired position, the line of force, and then draw a line that is perpendicular to the line of force and have it intersect the axis.  An example of the moment arm (rough estimate) to the coxofemoral joint (hip) at the starting position of a deadlift can be seen below:

Image courtesy of http://colinhaller.blogspot.com

Actually, you would need to lower the red line until it actually intersected with the axis of the coxofemoral joint, but hopefully the visual gives you a slight understanding of how moment arms can be found relative to the body.

Now, what if there is no moment arm to the joint, meaning the line of force goes directly through the axis of the joint?  A basic but crude/not completely accurate example of this would be at the top of a seated dumbbell shoulder press.

Image courtesy of broncofit.blogspot.com

In the picture on the right you can see that if you were to draw a straight line going up and down (ceiling to floor) through the middle of the handle of each respective dumbbell, that line would almost go right through each  respective axis of the glenohumeral (shoulder) joint.  This means that in this position there is almost no torque on that joint.  There are still joint forces, but there is almost no force that is creating rotation around the axis of that joint.
Compare that to this video:

 

Here we also have a shoulder press movement, but a completely different moment arm to the glenohumeral joint (GH).  Instead of there being a moment challenging humeral abduction et. al, there is now a moment challenging predominantly the external rotation capabilities of the GH, even though the motion is the same.  Can you see how the two moment arms are different?
Drop a comment below if I need to still clear some things up.

Your Body.  Your Training.

Get big or die tryin'.

Charlie Cates, MATs, CSCS
Self Made_®, Owner and Founder

Charlie Cates is a Muscle Activation Techniques_® specialist and a strength and conditioning specialist.  He is the owner and founder of Self Made_® (http://selfmadefitness.com/) in Chicago, IL.  He has worked with competitive and everyday athletes of all ages and ability levels, from 9-year-old kids to NFL MVP’s.  He can be reached via e-mail at charlie@selfmadefitness.com.
This article may be reproduced with biographical information intact.

The Front Squat vs. Back Squat

Image courtesy of benbruno.com

Back in February there was a series of articles written by Jim Reeves posted on Ben Bruno's website comparing front squats to back squats.  In the second article of this series, which can be found here, there are pictures of a man at the bottom of both his front squat and his back squat.  The pictures are then (poorly) analyzed for the motion that happened at specific joints throughout the movement and conclusions are drawn based on these measurements and then further discussed in the third installment of this article series, found here.

Now, I will not waste your time ranting about how poor of a job was done analyzing joint motion, but just so you know I am not full of crap, I will give you one example.

Image courtesy of benbruno.com

The caption for this photo reads "...the angle calculated for the hip and ankle motion measured at the bottom of the squat motion."  Two things.  First, where the shaded area is indicating "hip" motion, that is actually indicating how far forward the torso is leaning, the position of which is probably a product of both hip flexion and trunk flexion but the shaded area is really only indicating trunk motion relative to the alleged positioning of the femur.  Even then, the number is inaccurate because right now it would indicate that if your torso is fully folded up on top of your thighs you are very close to zero degrees of trunk/hip/whatever the heck he is trying to measure flexion when, in fact, 180 degrees of motion would be a more accurate assessment.  Likewise, in this picture, 136.2 degrees of motion would be the correct assessment of motion, assuming the depicted femur and spine positions are remotely accurate.

Second, and going along the same lines as what I just said, if you are actually looking at that picture and trying to determine "hip" motion, you, once again, have to look at the opposite side of the axis and measure to the femur rather than where the spine currently is relative to the femur.  Reason being when you stand straight up, as you normally do at the top of a squat, it would be said that you are in a position that is closer to zero degrees of hip flexion rather than 180 degrees of hip flexion.  Therefore, just as above, the number of degrees that are assigned to "hip flexion" should be much greater than what is currently presented in the article.

Okay, I tried to hold myself back from a rant.  I think I did alright.  If not, I apologize, but I felt it was a point that needed to be made.  Now, on to the major issue at hand.

So the issue, among other things, of joint motion is brought up in these articles and how during front squats there is "this much joint motion here" and during back squats there is "this much joint motion there", etc.  I have already demonstrated how these assessments are not accurately done, but nevertheless you can kind of eyeball it and see what they are talking about even though their numbers are off and therefore their argument is misguided.  BUT, but but but but BUT what was COMPLETELY left out of  the discussion was 1) placement of the load and 2) direction of the line of force.  Without knowing and/or discussing these, any argument being made in regards to muscular participation and requirement as well as the effects of the motion and load on the joints themselves is incomplete and, until this information is taken into consideration, invalid.

Why is the placement of the load and the direction of the force so important to know?  These variables help to determine the length of the moment arm (moment) of the resistance at each joint.  If you don't know the moment, you cannot determine the amount of torque that is occurring at the joint and, subsequently, you are unable to calculate the joint forces as well as the amount of force that has to be generated by the muscles in order to move that load.

The point that was never discussed in any of the four articles is that there are significantly different moments created to the ankles, knees, hips, and spinal levels, along with every other joint in the body that rests below the placement of the load, when comparing the front squat and back squat, not only at the bottom position, but at every position between the bottom and the top of the movement.

And that, in my opinion, is one of the most important factors that has to be considered when determining whether to prescribe front squats or back squats, or any exercise for that matter, to an individual.
Your Body.  Your Training.

Get big or die tryin'.

Charlie Cates, MATs, CSCS
Self Made_®, Owner and Founder

Charlie Cates is a Muscle Activation Techniques _® specialist and a strength and conditioning specialist.  He is the owner and founder of Self Made_® (http://selfmadefitness.com/) in Chicago, IL.  He has worked with competitive and everyday athletes of all ages and ability levels, from 9-year-old kids to NFL MVP’s.  He can be reached via e-mail at charlie@selfmadefitness.com.
This article may be reproduced with biographical information intact.

Flyes vs. Presses: A Joint Perspective

Let me ask you a question: What is the main difference between a dumbbell fly on a flat bench and a dumbbell press on a flat bench?

Now, there are a multitude of directions you could go with your answer, so for some semblance of direction we will say this question is to be looked at from the perspective of the joints involved in creating the respective motions.

Okay, that doesn't exactly narrow it down, either, because it could be correctly argued that every joint in the body is involved in both motions, but some joints have motion occurring at the joint while at other joints there isn't any motion occurring. SO, for sake of this post, I will once again narrow down the focus of my original question to say, "What is the main difference between a dumbbell fly on a flat bench and a dumbbell press on a flat bench from the prospective of the joints involved, with limiting the discussion to joints where there is motion at said joint?"

Longer than I had originally intended, but alas, hopefully my idea has been conveyed appropriately. So how would you answer this?

At first glance, almost everybody is going to cite the difference in elbow flexion and extension between the motions, and I would agree that is the main difference. Now, what would you say the second biggest difference is?

Here's the reason I bring this up: When looking at movements, don't just take into consideration the muscles that are allegedly working during said movement; look at the stress placed on the joints, as well. When you perform a flye on a flat bench, there is a tremendous about of stress placed on the gleno-humeral (GH) joint of the shoulder. The reason for the increased stress on this joint is because the moment arm of the applied force is significantly longer when the humerus is at 90 degrees of abduction and the elbow is in a position of 0 degrees of flexion (as is the case during a flye on a flat bench) than when the humerus is horizontally abducted and the elbow is flexed at approximately 90 degrees (as is the case during a dumbbell press on a flat bench).**

**Side note: An appropriate precursor to this post probably would have been along the lines of defining a moment arm and defining what abduction is in relation to the humerus. If you are confused, Google it, or drop a comment below and I'll make sure to post on these subjects in the future.

So, how much greater is the stress on the GH in this position? Well, this is going to vary completely on the individual. BUT, for the sake of this post, let's say the three divisions of pec major attach 1" away from the axis (the GH, in this case). We'll say the person's humerus is 10" long (the distance between GH and elbow) and the distance between the elbow and where the weight (length of radius and ulna plus some--RU+) is in their hand is 10". That means that at a position of 90 degrees of humeral abduction and 0 degrees of elbow flexion (flye) the length of that lever is 20", whereas at a position of 90 degrees of humeral abduction and 90 degrees elbow flexion (press) the length of that level is 10". There is also a component of external rotation, among other things, in both of these scenarios.

Let me stop here and say that this is an INCREDIBLY simplified model, with many, many assumptions, not the least of which is that the person in question can both achieve enough elbow extension to allow for a full ten inches of distance between the weight in their hand and the elbow joint as well as actually be in this much elbow extension at the bottom of their flye rep. Also, I would like to say that for this example we will not be taking into consideration the stress upon the joint at all of the infinite number of positions throughout the flye and press motions, nor will we be considering what is actually happening during the motions. I will simply (or not) be explaining the scenario from the two positions described--90 degrees of humeral abduction with 1) 0 degrees of elbow flexion and 2) 90 degrees of elbow flexion.

Okay, back to the numbers. First, let's look at the press.

At a position of 90 degrees of humeral abduction and 90 degrees of elbow flexion, there is a moment of resistance that is 10" long. The moment of effort is, as stated before, 1". Assuming the person is holding a 5-pound dumbbell, the fibers that horizontally adduct the humerus will have to generate 50 inch-pounds of force to horizontally adduct the humerus from that position. The 45-pound difference between the weight that is being held and the force that has to be generated to move it is what is placed on the GH.

Now, looking at the flye.

At a position of 90 degrees of humeral abduction and 0 degrees of elbow flexion, there is a moment of resistance that is 20" long. We still have the same 1" moment of effort and are using the same 5-pound dumbbell, BUT there will have to be 100 inch-pounds of force generated to horizontally adduct the humerus from this position. This will result in an excess of 95 pounds of force being placed upon the GH, over twice as much as with the press.

One could argue that you use less weight with a flye than with a press, so that might make the stress on the GH equal. True, but once we talk about actually moving the weight there are too many other variables to take into consideration because now we are talking about a moving resistance instead of a static resistance so inertia and other variables will come into play.

What is my point of writing this? It is not to say flyes are bad, or even that presses are superior or something along those lines. Quite frankly, the hierarchy of good and bad regarding different exercises is 100% based on the limitations of the individual performing them and his or her goals, so I could not logically talk about this in a blog post. My reason for writing this is to get you to think in a different light about the movements you are performing and the toll that they may or may not be taking on your body.

An Educated Approach To Training

If we all can begin to take a more educated approach to our training, one in which we actually understand what we are doing, we can begin to truly manipulate these variables to our advantage to create positive adaptations in a safe and effective manner instead of randomly flinging our bodies and weights in different directions and assuming the intended outcome will be the actual outcome.

Also, I am by no means an expert on the terminology I used in this post today, and this way of viewing movement is very new to my thought process. If you are and notice I have messed something up in my verbiage or explanation, please let me know via the comment section or e-mail at charlie@selfmadefitness.com. Many thanks!

Like, Tweet, drop a comment below, or share the knowledge!

Get big or die tryin'.

Charlie Cates, CSCS

Self Made®, Owner and Founder

Charlie Cates is a strength and conditioning specialist and the owner and founder of Self Made® (http://selfmadefitness.com/) in Chicago, IL. He has worked with competitive and everyday athletes of all ages and ability levels, from 9-year-old kids to NFL MVP’s. He can be reached via e-mail at charlie@selfmadefitness.com.

This article may be reproduced with biographical information intact.