Lecture Ten : Muscle III - Form and Actions at Joints
13 important questions on Lecture Ten : Muscle III - Form and Actions at Joints
Explain the 3 factors that affect muscle contraction/function?
- Length of muscle fibres : longer fibres can contract more (greater range of movement). Fibres can shorten up to 50% of their resting length during contraction.
- Number of muscle fibres : By increasing the number of muscle fibres, you increase the cross-sectional area of the muscle which is directly proportional to tension (can produce more contractile force).
- Arrangement of fibres : parallel or pennate(oblique) to the line of pull.
- PARALLEL : Increased shortening but can fit fever fibres in a given space (lower contractile force produced).
- PENNATE : Decreased shortening but can fit more fibres in a given space (higher contractile force produced).
Explain the different anatomical levers ?
- Lever = Bone
- Pivot/fulcrum = Joint
- Load = External or Internal force
- Pulling force = from muscle
Explain the 3 different Muscle Actions ?
- Concentric : Develops tension, muscle shortens and changes joint position.
- Isometric : Develops tension, but no change in muscle length or joint position.
- Eccentric : Develops tension, muscle lengthens and changes in joint position.
- Higher grades + faster learning
- Never study anything twice
- 100% sure, 100% understanding
For my 1st exam I got a C. Then, I started looking for ways to learn better and I came across Study Smart. Since then I have scored a A+, A, A- and another A. I highly recommend it to everyone who wants to hear it. I am so happy with it!!
I was struggling to finish all my first-year subjects for 3 years. Then I discovered Study Smart, which helped me to finish all of them within 3 months.
Because of StudySmart, things are going well in many ways. Before, I always had study stress and no time for anything. Now I feel calm and confident (because of the program). I used to score a B, now I usually score an A or A+.
Hey Chris, I really want to thank you very much for developing the platform, I usually got around C for my exams, now I scored an A+, an A and a A- !!
Since using Study Smart, my average has increased significantly. I even completed a statistics course with a A+ while I'm bad at statistics. I took on extra courses this year, because of Study Smart. Thanks so much!
Ever since I started studying with StudySmart I passed all my exams !!! No more re-sits!! At first, I was happy with a pass and now I only get good grades. Many thanks!
I aced all the courses I studied with Study Smart. For law, I first scored a D, and now an A! I’m 100% sure that I’ll pass all the courses I study with Study Smart.
I always thought I studied well. My grades were fine. I could never have imagined that applying these study skills would have such a huge and direct impact on my grades, my speed and the pleasure I have in learning.
For the first time, I finally feel totally confident about the way I learn. I have the perfect overview and make great progress in terms of speed and the grades I get. Thanks, Chris!
I immediately started to enjoy learning again, and my grades soared. All of a sudden, everything went better. I highly recommend Study Smart to all students..
Being able to create my materials online made the process of studying so much smoother and quicker. I no longer have to spend a huge amount of my time on creating my summaries.
At first, my notes were a mess. Now I use Study Smart to take my notes in a perfectly structured way. It helps me to save a lot of time and do other things I enjoy.
Students that study with Study Smart get better grades. The system applies all the learning methods in such a way that both well-performing students and students who struggle perform much better.
Hi Chris, I would like to thank you very much. Last year I scored C on a course, and this year I got an A+ thanks to your method! Thank you very much!
The largest effect is that my child is more enthusiastic about school! Every parent wants their children to be happy at school, Study Smart made it happen.
In high school, I failed several exams, and that has really changed now. I actually needed this tool very much back then. Since I started studying with StudySmart, I haven't had any D's. My average score is now an A and those are results I would have never had in the past
With my old method, I passed only 3 out of 8 courses. Since I started taking my notes digitally in Study Smart, I have passed all my courses on the first try. For me, StudySmart takes away the stress of wondering if I will pass or not.
Thanks to StudySmart, I passed all my exams, and with better grades than before! On top of that, I have mastered a very good study method now, which I am confident will help me earn my degree.
Explain the 4 different types of Muscle Roles and give an example for each ?
E.g Biceps branchii when lifting a weight.
2. Antagonist : Contracts eccentrically
E.g Triceps branchii when lifting a weight.
3. Stabilizer : Contracts isometrically
E.g Biceps branchii while holding a weight (not moving).
4. Neutralizer : Eliminates unwanted movement of another muscle.
Describe What a Deltoid muscle is ?
- Location : Lateral side of the shoulder joint.
- Origin : Pectoral girdle (scapula and clavicle).
- Insertion : Humerus.
- Concentric action/s :
- Anterior belly : Flexion at the shoulder.
- Posterior belly : Extension of the shoulder.
- Medial belly : Abduction of the shoulder.
Describe What are Biceps branchii muscles ?
- Location : Anterior of the radioulnar and elbow joints.
- Origin : Scaula.
- Insertion : Radial tuberosity.
- Concentric action/s : Flexion at the elbow and supination at the radioulnar joint.
Describe What are Triceps branchii muscles ?
- Location : Posterior of the elbow joint.
- Origin : Scapula and humerus.
- Insertion : Ulna.
- Concentric action/s : Extension at the elbow.
Describe What is a Illiopsoas muscle ?
- Location : Anterior of the hip joint.
- Origin : T12 - L5 vertebrae and anterior surface of the pelvis.
- Insertion : Femur.
- Concentric action/s : Flexion at the hip.
Explain What the Gluteus Maximus muscles are ?
- Location : Posterior to the hip joint.
- Origin : Pelvis and sacrum.
- Insertion : Iliotibial band and femur.
- Concentric action/s : Extension at the hip.
Explain What is a Quadriceps femoris muscle ?
- Location :
- VM, VI & VL : Anterior to the knee joint.
- Origin :
- VM, VI & VL : Femur.
- Insertion : Tibia and the patella tendon.
- Concentric action/s :
- RF : Flexion of the hip and extension of the knee.
- VM , VI & VL : Extension of the knee.
Describe the Hamstrings Muscle Group ?
- Location : Posterior of the hip and knee joint.
- Origin : Pelvis and femur.
- Insertion : Tibia and Fibula.
- Concentric action/s : Extension of the hip, flexion of the knee and rotation at the knee (when flexed).
Describe the Tibialis Anterior Muscle ?
- Location : Anterior of the ankle joint.
- Origin : Tibia.
- Insertion : Medial tarsals.
- Concentric action/s : Dorsiflexion.
Describe the Triceps Surae Muscle ?
- Location :
- S : Posterior to the ankle joint.
- Origin :
- G : Femur.
- S : Tibia and Fibula.
- Insertion : Calcaneus (heel bone) by Achilles tendon.
- Concentric action/s :
- G : Plantarflexion of the ankle and flexion at the knee.
- S : Plantarflexion at the ankle.
Try our study magic for free
a PDF, study it super fast
- No sign up, email or credit card needed!
- AI makes unlimited flashcards
- Get unlimited quizzes and tests
- Ask AI anything
- No sign up, email or credit card needed!
- Have and keep perfect overview
- Make flashcards, notes and mind maps
- Review, test and score!
The question on the page originate from the summary of the following study material:
- A unique study and practice tool
- Never study anything twice again
- Get the grades you hope for
- 100% sure, 100% understanding
