Dr. Goodin, the most interesting part of this video was understand moment arms and levers. I found it so hard to understand in my real biomechanics class where I could have just looked here for an awesome break down. I enjoyed the detailed and very interesting action of the patella in the mechanical advantages of the body, one of the few.
Thank you for this video Dr. Goodin. This was a good small refresher on muscle leverage in the body! I appreciate how you went over the different types of levers and how they influence the efficiency of movement and production of force!
This was a helpful refresher on what I learned in biomechanics! Classifying different levers can be challenging, but this video helps to go more in-depth on the differences and examples.
I enjoyed the way you explained the components of the levers. It is a concept I have always somewhat struggled with but the way you detailed it made it much easier to comprehend. It is interesting that the mechanical advantage or disadvantage is so dependent on how much force is necessary!
Have you ever thought of applying this to bodybuilding training, in example finding the best exercises for muscle growth biomechanically like Doug brignole has done?
@@joojotin Doug's exercise biomechanics insights are revolutionary. Better results with less time. Ex. Doug's 'early phase loading' principle helps eliminate useless exercises when you understand that there is a correlation between the strength curve of the muscle and the resistance curve of the exercise. So choosing the best exercises is key for better results.
I absolutely loved that you included the example regarding the patella's role for quad levers. So interesting to think about how intricately were are designed and how something so "small" really plays a huge part in affecting our mechanical advantage and also allows us to move better!
In anatomy and x phys and other courses we have talked about actin and myosin cross bridges. I had not put too much thought into levers and moment arms in terms of lifting. I think my favorite part of this lecture was seeing and learning about the comparison of the quadriceps both with and without the patella.
All the visuals provided help a lot when I'm trying to understand difficult topics. Trying to understand First-Class Levers was somewhat challenging and the visual makes everything connect
The way that you broke down the different levers was very helpful to me! I was a little confused regarding the chapter in the textbook but the way you described it, along with the visuals was very helpful to me.
I like how you always make sure to include a real life example like how when we do a push up, it is considered a second class lever. And it is interesting so see how our body has to work so hard for movements that we think are natural and easy. Also how can you tell how long the moment arm is?
Such a good refresher from the biomechanics class I was able to take with Professor Aguinaldo this past semester! Seeing these visuals always helps me better understand how our body works.
I really appreciated the different examples for each of the classes of levers. They were all blending together in my mind but the examples helped me understand the differences between each of them.
The breakdown of the three lever classes helped clarify some of the things I found confusing. It is also fascinating how much of our skeletal muscle operates at a mechanical disadvantage.
I liked how you gave examples of specific exercises for each of the levers because it helped me visualize between which muscles are resisting and operating when doing the movement. Great video!
Thank you so much for the video and information given. I am a visual learner so watching this video gave me better understanding opposed to reading info straight from the text
I thought the breakdown of mechanical advantages and disadvantages was super helpful. Understanding how crucial the moment arm plays in the two factors makes a tremendous difference.
Of all my years in anatomy I did not realize how crucial the patella actually is. Being a anchor for the quads as well as creating distance of the quadriceps tendon form the axis of rotation.
This really helped me understand levers better. It's crazy to think that most of our musculature is operating at a mechanical disadvantage. I found it interesting that when we test athletes' foot contact on force plates, the force shown is that produced by the feet however, what's not shown is the force that our musculature had to overcome because its operating at a mechanical disadvantage.
It is super interesting how even though it is shown that we produce a certain amount of force, we are actually producing even more due to the considerable mechanical disadvantages of our muscles.
The mechanical advantage part was really interesting to hear. I can see some parallels with the training videos at my work that teach us how to lift heavy objects easier.
Great topic: what would the class lever for a back squat be? Would the axis be the hip joint? Would the torso and the femur be considered the arms? There’s two reasons for these questions. 1. If the hip is the axis and the bar sits on the upper back while moving eccentricity(resistance) the force(weighted barbell) really isn’t on the posterior side of the axis. It’s sits just over the hips or possibly a little on the anterior side. 2. If a person is tall (6’6 or taller) they most likely have a long torso, femur and tibia bone which makes it a little harder to keep the bar over center of mass. PS I’m currently taking Kinesiology 😊
The three types of levers and how they effect force output was very interesting to learn about. I was shocked to hear that it takes 8x the force of the weight when working your triceps.
I thought the difference between the different classes of the lever classes were really interesting, and definitely something that I had not learned before.
Thank you for the video. As far as I understand, triceps extension is the 1st class level because the triceps is located on the opposite side of the fulcrum relatively to the resistance. However, leg extension is the 3rd class level because the rectus femoris insertion is anterior side of the tibia which is in between the fulcrum and the resistance. Why for triceps extension, we look at where the triceps is located (posterior to the humerus) not on its insertion (posterior to the ulna, which on the same side as the resistance relatively to the fulcrum in triceps extension) but for leg extension we look at the rectus femoris insertion which is the tibia? Thank you
Great videos - but question - when we are observing how the moment arm changes for the resistive force at 16:20, we are looking at a bicep curl. You say 'this is all just for a first class lever' but wouldn't a bicep curl be a third class lever?
I have messed up with the angle of pull , they say when the angle 90° there is rotatory force, >90 dislocation ... could you plz explain that point ? Thank you
How exactly do get the measurements? When you were going over the different classes of levers, I saw the measurements on the images and couldn't figure out how you came up with the numbers. I feel like it's not as easy as just getting a ruler, but I could be wrong lol
Yeah levers can be tricky. To measure the moment arms, you can simply measure the distance between the force applied and the fulcrum. The hard part comes with identifying exactly WHERE the force is transferred from the muscle to the moment arm. It sometimes acts through a bony protrusion/structure like at the elbow or knee.
Dr. Goodin, do you have another video, or something else that can help me visually see the information about angular velocity? as it relates to during concentric muscle action, as angular velocity increases, torque decreases? I want to see this in action. to help make sense. I think I get it, because of the example in the book about a biceps curl, but I think if I saw it in action, with explanation, I could make sure I do actually understand.
hmm you might check out my biomechanics playlist, and I believe we get into some angular velocity calculations. That said I stopped teaching that course after COVID due to shifting teaching load so the playlist is incomplete. A better example though would be to learn about how gearing ratios work on bikes or cars. I'm no mechanic but there are plenty of great YT explanations out there!
@@DrJacobGoodin thanks! I will watch all of those videos and then also check out your suggestions. I saw a post when I did a quick google search that mentioned that but I didn’t open it up yet.
hi dr.goodin nice shirt like the check mark lol. But I didn't though there was so many different levers in the body although it would makes sense because every body part is different lengths.
The example of plantarflexion as a second-class lever is misleading at best. It is most simply described as a first-class lever with ground reaction force acting as the resistance force, the calves acting as the applied force, and the axis at the ankle joint. If using the given diagram and the second-class lever model with the axis at the MTP joints, then one must also include the reaction force of the tibia on the talus. The harder the calves contract, the higher this contact force will be. This will show that the calves need to contract with a force greater than body weight throughout most of the range of motion of plantarflexion. To be fair, this inaccuracy is in almost every biomechanics and exercise textbook I have ever seen.
Yeah buddy, it's just taking longer than I hoped to get into the swing of our semester! Hoping to start in on it end of this week or early next, but I've been saying that for awhile so we'll see...
Having taken Biomechanics a year ago, this was a great refresher on leverage and how moment arms work. The piece about how the patella allows for an increase force production is fascinating to me, because despite not being a very thick bone, it still plays a key role in force generation. I tend to mix up the types of levers but I think remembering the muscular examples for each would be very beneficial.
Regarding the gastrocnemius and soleus acting at the ankle joint, this does not constitute a second class lever. I know variations of this diagram are in virtually every biomechanics and physical therapy book, but they are wrong. The axis about which there is a tug of war between body weight and the gastrocnemius is the ankle joint, not the fulcrum between the ball of the foot and body weight. If the overall line of gravity of body weight was centered over the ankle, the person would be falling over backward. If the person is balanced, the line of gravity must line through the base of support, in this example, the heads of the metatarsals and the toes. You can in fact analyze the movement about the axis between the ball of the foot and the floor, but you need to use the total of forces pushing down through the ankle. This includes the compressive force from body weight (minus the foot, which would need to be addressed separately) and the compressive force from the gastrocnemius and soleus. This will show there is not really a mechanical advantage. Through analysis at the ankle, you can see the that gastrocnemius and ankle are part of a first class lever system. This results in mechanical disadvantage through most of standing plantar flexion, but the gastrocnemius may reach a slight mechanical advantage at full plantar flexion. This is not a personal critique of Dr. Goodin. I just started watch his videos and I am very impressed.
This was a super interesting video as I have never had a good description of lever in the body. The classes are still a little confusing for me but I can always come back to this video and watch again. Excited to dive into how levers give advantages and disadvanatges for different workouts and even different body types!
Having already taken a biomechanics course and enjoyed it, I found this video to be a great refresher. Kinetic and kinematic can be confusing but having a clear definition always helps.
Thank you Dr. Goodin for the refresher on biomechanics as I took it with Dr.A last fall. Reviewing the levers and how different forces affect the moment arms and force.
Learning about muscle leverage through the textbook was tricky for me because I was unable to picture it in my head. However, your demonstration of what a lever is with your pen was extremely helpful. Thank you!!
It is interesting to dive into the physics and mechanics of muscle movement how muscles pull at certain angles to create force and where those forces are being applied. It was also interesting to see which joints were associated with each type of lever.
I really enjoyed watching this video on biomechanics and muscle leverage. I have never taken a biomechanics class before so i felt this was a good introduction for myself
I just took Biomechanics last semester and definitely already needed a refresher. I appreciate the depth you went into on levers. Listening to explanations is much easier for me to understand as opposed to reading in the textbook.
I appreciated the introduction into the three classes of levelers in biomechanics. It's a little tricky to understand but I felt like you've done a great job at helping me.
Learning about the mechanical advantages was really interesting to me because I had never learned that there are certain movements in which our muscles have an advantage, which makes it easier for us to lift more weight.
A one to eight mechanical disadvantage for triceps is crazy! I never thought about the physics of different joints. Give me a long enough lever and a fulcrum which I can place it and I can move the world I guess :p
The wheel barrow example was awesome to remember the second class lever by! P.S. I will now squat and occasionally envision the patella's movement giving me power.
In this video, I learned about the biomechanics of the three different types of levers, while also applying those concepts to mechanical advantages and disadvantages.
Pronator teres is also a flexor of the elbow joint. I would argue that pronator teres is best described as an agonist during elbow flexion. If one focused on supination during elbow flexion, either dynamically or isometrically, then I would argue pronator teres is best described as a synergist. There is definitely some inherent ambiguity in muscle classification depending on the details of any given movement.
I found it super interesting that most of the skeletal muscles in the body operate at considerable mechanical disadvantages. I don't know why, but I kind of assumed that most muscles were working in advantageous conditions.
Would this mean that having a shorter bicep with a longer tendon would have less of a mechanical disadvantage than a long bicep? Everywhere I search, it says there is no difference in strength.
It is interesting to dive into the physics and mechanics of muscle movement how muscles pull at certain angles to create force and where those forces are being applied. It was also interesting to see which joints were associated with each type of lever.
I thought the comparison between the second class leaver and a wheel barrier made much more sense on the reason for there being a mechanics advantage behind the muscle movement. The reading was difficult for me to follow, this video helped clarify things for me.
Are there any other ways to directly test to amount of mechanical stress put on muscles and tendons besides a force plate? It is weird to think your muscles are for the most part at a constant disadvantage but are still able to overcome that and recover during sports.
Little interesting tidbit in practice: If your family tends to have muscles that attach further out on the skeleton than is considered quote on quote normal, everyone in said family is an absolute monster in terms of strength
Not having taken biomechanics this is a pretty confusing topic at first. As the video goes on though it was easier to understand with the many examples given.
So cool with 2nd class levers like the ankle that the calves and soleus can lift our whole bodies due to the mechanical advantage, even though they are relatively smaller muscles.
Wow, I never realized that the knee cap was more than just a bony pad to stop the tendon from rubbing on the bone! I always thought it was simply to reduce friction, but it also acts as a psuedo-pulley to increase the amount of force that is translated from the quadriceps, making the system just a little more efficient. The human body really is amazing.
It is so crazy how you've done 1,000 bicep curls today! Lol. I never thought how the pronator teres muscle could be a synergist to a biceps curl because they seem like completely unrelated muscles. However after you explain it, it makes so much sense! Thanks for helping me think outside the box.
As a Strength and Conditioning coach, how often is it that you would be calculating the torque or force on an athelte? That looked like a lot of math, and math is hard :'(
Torque, maybe not so much, but it's important to understand the principle. Force, most likely very often if you're doing some kind of athlete monitoring using modern tools. At PLNU my research team along with the strength and conditioning staff monitors force output (albeit using a different method) up to twice a semester for most teams.
When looking at force production and also programming in general. How do you use this concept in exercise selection? Isometric, eccentrics for example and when to use them?
Yeah good question George. Sometimes it might affect your selection based on muscle contraction type like you say. More often in my coaching though I'm thinking about the force requirements of the sport and then doing my best to overload or at least match those demands in the training. Would love to go more in depth in future videos on that topic
@@DrJacobGoodin A future video covering some applications would be great! Thank you for your response, that actually makes perfect sense when applying specificity of training. Thanks!
I really loved that you included the example of the patella's role in quad levers. It's fascinating to consider how intricately we’re designed, and how something seemingly "small" plays such a significant role in improving our mechanical advantage and enabling smoother movement!
The wheelbarrow example really helped me understand exactly what creates leverage. I also think it’s really cool that we can determine whether a muscle is at a mechanical advantage or disadvantage based on whether the equation AF/RF comes out to a number lower or higher than one.
Thank for this quick introduction on levers. Skeletal muscles are way more complicated than they seem with all the biomechanics involved
Having the pictures of the muscles along with the descriptions of different classes of levers helped a lot. Thank you!
Dr. Goodin, the most interesting part of this video was understand moment arms and levers. I found it so hard to understand in my real biomechanics class where I could have just looked here for an awesome break down. I enjoyed the detailed and very interesting action of the patella in the mechanical advantages of the body, one of the few.
I'm slowly turning from a gym rat to a biomechanics expert. Thank you for this golden information.
Thank you for this video Dr. Goodin. This was a good small refresher on muscle leverage in the body! I appreciate how you went over the different types of levers and how they influence the efficiency of movement and production of force!
This was a helpful refresher on what I learned in biomechanics! Classifying different levers can be challenging, but this video helps to go more in-depth on the differences and examples.
I enjoyed the way you explained the components of the levers. It is a concept I have always somewhat struggled with but the way you detailed it made it much easier to comprehend. It is interesting that the mechanical advantage or disadvantage is so dependent on how much force is necessary!
Have you ever thought of applying this to bodybuilding training, in example finding the best exercises for muscle growth biomechanically like Doug brignole has done?
Every serious strength trainee needs to buy Doug's book 'The Physics of Resistance Exercise' - best investment you'll make!
@@nelacostabianco what kind of results did you get with it?
@@joojotin Doug's exercise biomechanics insights are revolutionary. Better results with less time. Ex. Doug's 'early phase loading' principle helps eliminate useless exercises when you understand that there is a correlation between the strength curve of the muscle and the resistance curve of the exercise. So choosing the best exercises is key for better results.
@@nelacostabianco absolutely agree
I absolutely loved that you included the example regarding the patella's role for quad levers. So interesting to think about how intricately were are designed and how something so "small" really plays a huge part in affecting our mechanical advantage and also allows us to move better!
In anatomy and x phys and other courses we have talked about actin and myosin cross bridges. I had not put too much thought into levers and moment arms in terms of lifting. I think my favorite part of this lecture was seeing and learning about the comparison of the quadriceps both with and without the patella.
All the visuals provided help a lot when I'm trying to understand difficult topics. Trying to understand First-Class Levers was somewhat challenging and the visual makes everything connect
Hearing the explanation of the different levers really helps me grasp how each works.
The way that you broke down the different levers was very helpful to me! I was a little confused regarding the chapter in the textbook but the way you described it, along with the visuals was very helpful to me.
Awesome video for those not only studying for the CSCS but also for general knowledge. Very helpful!
The photos really helped get a better grasp on what a moment arm is, after just reading the chapter.
I like how you always make sure to include a real life example like how when we do a push up, it is considered a second class lever. And it is interesting so see how our body has to work so hard for movements that we think are natural and easy. Also how can you tell how long the moment arm is?
This video is very helpful and a great refresher from biomechanics class from 2 semesters ago
Such a good refresher from the biomechanics class I was able to take with Professor Aguinaldo this past semester! Seeing these visuals always helps me better understand how our body works.
I really appreciated the different examples for each of the classes of levers. They were all blending together in my mind but the examples helped me understand the differences between each of them.
The breakdown of the three lever classes helped clarify some of the things I found confusing. It is also fascinating how much of our skeletal muscle operates at a mechanical disadvantage.
I liked how you gave examples of specific exercises for each of the levers because it helped me visualize between which muscles are resisting and operating when doing the movement. Great video!
Interesting to learn about how force relates to muscular movement! Excited to learn more about this in Biomechanics this semester.
I always had trouble grasping the concept of muscle leverages and moment arms. This video helped me gain more understanding of both of these topics!
Taking a lot of notes and digesting a lot of these concepts, thoroughly. Not perfect nor an expert but definitely believe I am learning greatly.
I like how you explained mechanical advantage with drawings because it helped me visual what is taking place! Thank you!
Thank you so much for the video and information given. I am a visual learner so watching this video gave me better understanding opposed to reading info straight from the text
I thought the breakdown of mechanical advantages and disadvantages was super helpful. Understanding how crucial the moment arm plays in the two factors makes a tremendous difference.
Thanks for the explanation of the levers, It was nice to review because I had struggled with this in biomechanics
I am feeling ready for the quizz tomorrow !
Of all my years in anatomy I did not realize how crucial the patella actually is. Being a anchor for the quads as well as creating distance of the quadriceps tendon form the axis of rotation.
I appreciate the biomechanics refresher!
This really helped me understand levers better. It's crazy to think that most of our musculature is operating at a mechanical disadvantage. I found it interesting that when we test athletes' foot contact on force plates, the force shown is that produced by the feet however, what's not shown is the force that our musculature had to overcome because its operating at a mechanical disadvantage.
This video does a really good job at explaining the three different levers. Thank you!
It is super interesting how even though it is shown that we produce a certain amount of force, we are actually producing even more due to the considerable mechanical disadvantages of our muscles.
The mechanical advantage part was really interesting to hear. I can see some parallels with the training videos at my work that teach us how to lift heavy objects easier.
Great topic: what would the class lever for a back squat be? Would the axis be the hip joint? Would the torso and the femur be considered the arms? There’s two reasons for these questions. 1. If the hip is the axis and the bar sits on the upper back while moving eccentricity(resistance) the force(weighted barbell) really isn’t on the posterior side of the axis. It’s sits just over the hips or possibly a little on the anterior side. 2. If a person is tall (6’6 or taller) they most likely have a long torso, femur and tibia bone which makes it a little harder to keep the bar over center of mass. PS I’m currently taking Kinesiology 😊
The three types of levers and how they effect force output was very interesting to learn about. I was shocked to hear that it takes 8x the force of the weight when working your triceps.
Stupendous video Jacob!
I thought the difference between the different classes of the lever classes were really interesting, and definitely something that I had not learned before.
I don't know who would give a dislike for such an informative video for free. Must have been the bicep joke.
Thank you for the video. As far as I understand, triceps extension is the 1st class level because the triceps is located on the opposite side of the fulcrum relatively to the resistance. However, leg extension is the 3rd class level because the rectus femoris insertion is anterior side of the tibia which is in between the fulcrum and the resistance. Why for triceps extension, we look at where the triceps is located (posterior to the humerus) not on its insertion (posterior to the ulna, which on the same side as the resistance relatively to the fulcrum in triceps extension) but for leg extension we look at the rectus femoris insertion which is the tibia? Thank you
nice video Dr. G!
These videos are absolutely brilliant!! Very informative and immersive😀. They are really helping my studying, thank you😀.
Do you do any audio blogs?
Thanks Lee! Working on getting a podcast going sometime this year. I'll announce it here when I do
Great videos - but question - when we are observing how the moment arm changes for the resistive force at 16:20, we are looking at a bicep curl. You say 'this is all just for a first class lever' but wouldn't a bicep curl be a third class lever?
You're correct! The biceps is a 3rd class lever, thank you for pointing that out @bdakridge17, much appreciated.
would it be possible to focus only the biceps brachii only and not use the pronator teres even indirectly?
yes if you supinate through the movement on the concentric, then you're going to increase bicep activation
I have messed up with the angle of pull , they say when the angle 90° there is rotatory force, >90 dislocation ... could you plz explain that point ? Thank you
How exactly do get the measurements? When you were going over the different classes of levers, I saw the measurements on the images and couldn't figure out how you came up with the numbers. I feel like it's not as easy as just getting a ruler, but I could be wrong lol
Yeah levers can be tricky. To measure the moment arms, you can simply measure the distance between the force applied and the fulcrum. The hard part comes with identifying exactly WHERE the force is transferred from the muscle to the moment arm. It sometimes acts through a bony protrusion/structure like at the elbow or knee.
Dr. Goodin, do you have another video, or something else that can help me visually see the information about angular velocity? as it relates to during concentric muscle action, as angular velocity increases, torque decreases? I want to see this in action. to help make sense. I think I get it, because of the example in the book about a biceps curl, but I think if I saw it in action, with explanation, I could make sure I do actually understand.
hmm you might check out my biomechanics playlist, and I believe we get into some angular velocity calculations. That said I stopped teaching that course after COVID due to shifting teaching load so the playlist is incomplete.
A better example though would be to learn about how gearing ratios work on bikes or cars. I'm no mechanic but there are plenty of great YT explanations out there!
@@DrJacobGoodin thanks! I will watch all of those videos and then also check out your suggestions. I saw a post when I did a quick google search that mentioned that but I didn’t open it up yet.
hi dr.goodin nice shirt like the check mark lol. But I didn't though there was so many different levers in the body although it would makes sense because every body part is different lengths.
The example of plantarflexion as a second-class lever is misleading at best. It is most simply described as a first-class lever with ground reaction force acting as the resistance force, the calves acting as the applied force, and the axis at the ankle joint. If using the given diagram and the second-class lever model with the axis at the MTP joints, then one must also include the reaction force of the tibia on the talus. The harder the calves contract, the higher this contact force will be. This will show that the calves need to contract with a force greater than body weight throughout most of the range of motion of plantarflexion. To be fair, this inaccuracy is in almost every biomechanics and exercise textbook I have ever seen.
Everytime I do bicep curls from now on im going to think about how its a third class lever
Hi Doctor, are you going to be finishing this playlist with the other chapters any time soon? Not trying to rush you or anything! Just curious.
Yeah buddy, it's just taking longer than I hoped to get into the swing of our semester! Hoping to start in on it end of this week or early next, but I've been saying that for awhile so we'll see...
THANK YOU SO MUCH for these instructional videos. Absolutely great dissection of relatively complex topics!
Having taken Biomechanics a year ago, this was a great refresher on leverage and how moment arms work. The piece about how the patella allows for an increase force production is fascinating to me, because despite not being a very thick bone, it still plays a key role in force generation. I tend to mix up the types of levers but I think remembering the muscular examples for each would be very beneficial.
Regarding the gastrocnemius and soleus acting at the ankle joint, this does not constitute a second class lever. I know variations of this diagram are in virtually every biomechanics and physical therapy book, but they are wrong. The axis about which there is a tug of war between body weight and the gastrocnemius is the ankle joint, not the fulcrum between the ball of the foot and body weight. If the overall line of gravity of body weight was centered over the ankle, the person would be falling over backward. If the person is balanced, the line of gravity must line through the base of support, in this example, the heads of the metatarsals and the toes. You can in fact analyze the movement about the axis between the ball of the foot and the floor, but you need to use the total of forces pushing down through the ankle. This includes the compressive force from body weight (minus the foot, which would need to be addressed separately) and the compressive force from the gastrocnemius and soleus. This will show there is not really a mechanical advantage. Through analysis at the ankle, you can see the that gastrocnemius and ankle are part of a first class lever system. This results in mechanical disadvantage through most of standing plantar flexion, but the gastrocnemius may reach a slight mechanical advantage at full plantar flexion.
This is not a personal critique of Dr. Goodin. I just started watch his videos and I am very impressed.
This was a super interesting video as I have never had a good description of lever in the body. The classes are still a little confusing for me but I can always come back to this video and watch again. Excited to dive into how levers give advantages and disadvanatges for different workouts and even different body types!
Having already taken a biomechanics course and enjoyed it, I found this video to be a great refresher. Kinetic and kinematic can be confusing but having a clear definition always helps.
Thank you Dr. Goodin for the refresher on biomechanics as I took it with Dr.A last fall. Reviewing the levers and how different forces affect the moment arms and force.
Learning about muscle leverage through the textbook was tricky for me because I was unable to picture it in my head. However, your demonstration of what a lever is with your pen was extremely helpful. Thank you!!
Hi Dr. Jacob. Congratulations, this video was amazing. Please, could you inform the reference (book or article) from the pitcures?
It is interesting to dive into the physics and mechanics of muscle movement how muscles pull at certain angles to create force and where those forces are being applied. It was also interesting to see which joints were associated with each type of lever.
I really enjoyed watching this video on biomechanics and muscle leverage. I have never taken a biomechanics class before so i felt this was a good introduction for myself
I took biomechanics and muscle leverage was a little difficult for me to understand, and you explained it well! This was a great refresher
I just took Biomechanics last semester and definitely already needed a refresher. I appreciate the depth you went into on levers. Listening to explanations is much easier for me to understand as opposed to reading in the textbook.
I appreciated the introduction into the three classes of levelers in biomechanics. It's a little tricky to understand but I felt like you've done a great job at helping me.
Learning about the mechanical advantages was really interesting to me because I had never learned that there are certain movements in which our muscles have an advantage, which makes it easier for us to lift more weight.
Biomechanics was a class I struggled to remember terms and concepts. Having an overview, especially on the three different levers really helped.
Helpful review of all the biomechanics that is definitely a little rusty after a year! very detailed video!
A one to eight mechanical disadvantage for triceps is crazy! I never thought about the physics of different joints. Give me a long enough lever and a fulcrum which I can place it and I can move the world I guess :p
The wheel barrow example was awesome to remember the second class lever by!
P.S. I will now squat and occasionally envision the patella's movement giving me power.
In this video, I learned about the biomechanics of the three different types of levers, while also applying those concepts to mechanical advantages and disadvantages.
Pronator teres is also a flexor of the elbow joint. I would argue that pronator teres is best described as an agonist during elbow flexion. If one focused on supination during elbow flexion, either dynamically or isometrically, then I would argue pronator teres is best described as a synergist. There is definitely some inherent ambiguity in muscle classification depending on the details of any given movement.
I found it super interesting that most of the skeletal muscles in the body operate at considerable mechanical disadvantages. I don't know why, but I kind of assumed that most muscles were working in advantageous conditions.
Would this mean that having a shorter bicep with a longer tendon would have less of a mechanical disadvantage than a long bicep? Everywhere I search, it says there is no difference in strength.
I have not taken biomechanics yet but this little intro to it makes me excited to take the course!
It is interesting to dive into the physics and mechanics of muscle movement how muscles pull at certain angles to create force and where those forces are being applied. It was also interesting to see which joints were associated with each type of lever.
I thought the comparison between the second class leaver and a wheel barrier made much more sense on the reason for there being a mechanics advantage behind the muscle movement. The reading was difficult for me to follow, this video helped clarify things for me.
we lift more weight in calf or barbell squat can you explain
It was really interesting to learn about the concepts of levers and how the forces that levers produce apply to different parts of the body.
Are there any other ways to directly test to amount of mechanical stress put on muscles and tendons besides a force plate? It is weird to think your muscles are for the most part at a constant disadvantage but are still able to overcome that and recover during sports.
Little interesting tidbit in practice: If your family tends to have muscles that attach further out on the skeleton than is considered quote on quote normal, everyone in said family is an absolute monster in terms of strength
Not having taken biomechanics this is a pretty confusing topic at first. As the video goes on though it was easier to understand with the many examples given.
So cool with 2nd class levers like the ankle that the calves and soleus can lift our whole bodies due to the mechanical advantage, even though they are relatively smaller muscles.
This really helped me understand the different classes of levers and it makes sense now! Thank you
I had never heard of a first class lever but now the next time I go to a gym and do tricep extensions I will understand what is happening.
I found the segment on the patella and its affect of leverage advantage very interesting. I had no idea it was optimal to have a patella for leverage.
Just a question: If you looked at where the tendon of the Triceps inserts, would that not make it a third class lever?
Really helpful video and the relativity to the strength aspect of it made it easier to understand.
Can you make a video on how muscles change shape and lever arms when moved over other joints?
I had not known the difference between each lever class before watching this video.
The way of treatment from sports injury
Wow, I never realized that the knee cap was more than just a bony pad to stop the tendon from rubbing on the bone! I always thought it was simply to reduce friction, but it also acts as a psuedo-pulley to increase the amount of force that is translated from the quadriceps, making the system just a little more efficient. The human body really is amazing.
Mine is also a percussion instrument thanks to all the cracking and popping from years of running!
It is so crazy how you've done 1,000 bicep curls today! Lol. I never thought how the pronator teres muscle could be a synergist to a biceps curl because they seem like completely unrelated muscles. However after you explain it, it makes so much sense! Thanks for helping me think outside the box.
haha I was just doing my best Anchor Man impression. My biceps tendon feels inflamed just thinking about doing 1000 curls in a day...
As a Strength and Conditioning coach, how often is it that you would be calculating the torque or force on an athelte? That looked like a lot of math, and math is hard :'(
Torque, maybe not so much, but it's important to understand the principle. Force, most likely very often if you're doing some kind of athlete monitoring using modern tools. At PLNU my research team along with the strength and conditioning staff monitors force output (albeit using a different method) up to twice a semester for most teams.
Well explained as usual❤️
When looking at force production and also programming in general. How do you use this concept in exercise selection? Isometric, eccentrics for example and when to use them?
Yeah good question George. Sometimes it might affect your selection based on muscle contraction type like you say. More often in my coaching though I'm thinking about the force requirements of the sport and then doing my best to overload or at least match those demands in the training. Would love to go more in depth in future videos on that topic
@@DrJacobGoodin A future video covering some applications would be great! Thank you for your response, that actually makes perfect sense when applying specificity of training. Thanks!
I've never studied muscles and exercise from a biomechanics point of view and this was very interesting!
*biomechanical haha
I really loved that you included the example of the patella's role in quad levers. It's fascinating to consider how intricately we’re designed, and how something seemingly "small" plays such a significant role in improving our mechanical advantage and enabling smoother movement!
The wheelbarrow example really helped me understand exactly what creates leverage. I also think it’s really cool that we can determine whether a muscle is at a mechanical advantage or disadvantage based on whether the equation AF/RF comes out to a number lower or higher than one.
This was a very helpful video. I was a little confused with the levers, but the wheelbarrow analogy perfectly clarified it. Thank you!