W4 Review - HES 105

What has to do with changing the frequency at which motor neurons stimulate their muscle fibers?

rate

T or F? Wave summation occurs when motor units are stimulated fast enough that they haven't fully relaxed before more corss bridges are formed.

T

Which factors alter the number of motor units that are recruited during a contraction?

amount of stimulus from the central nervous system, excitability of motor units

When will large SO fibers recruit compared to smaller SO fibers?

at the same time

When would smaller motor neurons recruit when compared to larger motor neurons?

before larger motor neurons

When would slow-twitch motor unit recruitment occur when compared to fast-twitch?

before fast-twitch

T or F? Inter-muscle coordination involves making sure that all the motor units in a muscle as working together as efficiently as possible.

F

What is the least fatigable fiber type?

SO

What is the strongest fiber type?

FG

T or F? Following a twitch, FOG fibers relax more quickly than SO fibers.

T

Which fiber type has the most stored triglycerides?

SO

Which fiber type has the lowest mitochondrial content?

FG

Which fiber type has the most phosphofructokinase?

FG

T or F? Muscle tension must be greater than load for a dynamic contraction to occur.

F

When do concentric contractions occur?

when muscle tension leads to shortening

Muscles with what are capable of more forceful contractions?

larger cross sectional area

T or F? More tension is possible with concentric compared to eccentric contractions.

F

What factors explain the relationship between force and velocity for CONCENTRIC contractions?

you can form the most cross bridges when you have more time (slower shortening), more cross bridges means more tension

What factors explain the relationship between force and velocity for ECCENTRIC contractions?

cross-bridges and titin provide more additional force when they are more stretched (with faster lengthening contractions), cross-bridges and titin both generate additional force during contraction when they are stretched

What kind of training offers a lot of promise because it can provide a greater training stimulus for a lesser physiological strain.

eccentric

T or F? Sarcomeres have an optimal length where maximum tension is the greatest. At longer and shorter lengths, the maximum possible tension will be reduced.

T

T or F? Maximum force (or torque) is always greatest at an intermediate joint angle - and larger and smaller angles the maximum possible force will always be reduced.

F

T or F? For concentric contractions, more tension is possible with slower contractions.

T

T or F? Muscle length is the only factor that affects the relationship between joint angle and maximum force.

F