Improving Muscle Performance Flashcards
What is the only biologic tissue capable of actively generating tension?
muscle
What is a prime agonist?
The muscle that is directly responsible for producing movement
What is a synergist?
The muscle that provides cooperative muscle function in relation to the agonist
Synergists function as either _____ or _____.
stabilizers or neutralizers
What is a stabilizer?
The muscle that contracts statically to steady or support some part of the body against the pull of the contracting muscle
What is a neutralizer?
The muscle that acts to prevent an undesired action of one of the movers
What is an agonist?
The muscle that has an effect opposite to that of the agonist
When does a concentric contraction occur?
When the tension generated by the agonist muscle is sufficient to overcome an external force and to move the body segment of one attachment toward the segment of its other attachment
Does a muscle that eccentrically contracts lengthen?
No, it merely returns from its shortened position to its normal resting length
What type of activities are eccentric contractions involved in?
activities that require deceleration to occur
Eccentric contractions generate forces ____ than isometric or concentric
greater
During an eccentric contraction the load exceeds the contractile force, how does this effect the cross bridges between actin and myosin
Some of the myosin filaments are torn from the binding sites on the actin filament while the remainder complete the contraction cycle
What are the 2 reasons tension is greater in a lengthening muscle than the tension that could be created during a shortening muscle action
- The combined increase in force per cross-bridge
- The number of active cross-bridges
What is an isokinetic contraction?
A contraction in which the muscle is maximally contracted at the same speed throughout the whole range of it related lever
What is required in order to perform an isokinetic contraction?
Special equipment that produces an accommodating resistance
What are the advantages of isokinetic contractions?
Both high-speed/low-resistance and low-speed/high-resistance regimens result in excellent strength gains
What are the disadvantages of isokinetic contractions?
- it is very expensive
- there is the potential for impact loading and incorrect joint axis alignment
- also has questionable functional carryover
What is an econcentric contraction?
A contraction that combines both a controlled concentric and a simultaneous eccentric contraction of the same muscle over two separate joints
What is an example of an econcentric contraction?
A standing hamstring curl in which the hamstrings work concentrically while the hip flexes eccentrically to lengthen the hamstrings
What is an isolytic contraction?
a type of eccentric contraction that makes use of a greater force than the patient can overcome
What is the difference between an isolytic and an eccentric contraction?
An eccentric contraction is voluntary whereas an isolytic contraction is involuntary
When can you utilize an isolytic contraction as a PT?
In certain manual techniques to stretch fibrotic tissue
The ability of a muscle to carry out its various roles is a measure of what?
muscle performance
Muscle performance is measured using what 3 things?
- strength
- endurance
- power