Motor unit activation and time-course of training adaptations Flashcards
What are muscle fibres innervated by?
Motor Neurons
What is the neuromuscular gathering called?
Motor unit
What is the size principle?
Recruitment occurs from largest groups to smallest depending on demands
What are low threshold motor units mostly made up of?
Type 1 muscle fibres
What type of motor units are recruited first?
small/lower threshold motor units
As tension increases, why are large motor units recruited?
to maintain mechanical tension
What are the variables of a resistance training programme?
-Choice of exercise
-order of exercise
-training load
-training volume (important determinant overtime of muscle hypertrophy)
-rest intervals
-repetition velocity
-training frequency
-time-under-tension/ velocity (slow/fast)
-muscle action (EC, CC, IC)
What resistance training should you be doing to develop endurance?
low weight, high reps
What did Aagard et al (2001) discover?
A total muscle fibre (type 1 and 2) increased by 16% which may be explained by the 18% increase in type 2 after 14 weeks of lower limb resistance training (4-5 reps of hack squats, inclined leg-press, isolated knee extension, hamstring curls and calf raises at 3-10RM)
Do body builders or weight lifters have a larger type 1 muscle fibre cross-sectional area?
-body builders- train with moderate loads with many sets and reps to build muscle mass.
Why is strength an development rapid?
due to neuronal adaptations to resistance training (proceeds the development of muscle mass)
What did Brook et al, 2015, find in his study with 10 young males for a 6 week progressive resistance training?
-training 1 leg at 75% 1RM using knee extensions
-trained leg= increase in strength and mass
-untrained leg= neuronal adaptations lead to the strength increase in the untrained leg but gained no change in muscle mass
Is their a relationship between strength and muscle size?
muscle may not change in size but strength of the muscle can increase fairly quickly
What did Dankel et al (2016) discover regarding the relationship between strength and muscle hypertrophy?
-5 individuals performed 1RM and maximal voluntary contraction for unilateral elbow flexion on 1 arm while the other arm performed the same plus 3 sets of exercise at 70% 1RM for 21 days
-testing arm did not increase in muscle thickness, training arm did develop in hypertrophy
-development in strength was identical between arms
Which muscles appear to elicit greater hypertrophy with resistance exercise?
Upper body muscle due to fibre composition
What do you have to do if you are more well trained?
train more frequently or incorporate an unaccustomed stimulus to result in a large MPS responseW
Why is MPS high for extended periods of time in the recovery period for untrained individuals?
to repair damaged muscle proteins
Why do you have to train muscle groups more frequently to reach muscle hypertrophy, in trained individuals?
rate of MPS is a much shorter time frame but to the same extent
What % of strength and cross-sectional area do female skeletal muscles have compared to men?
60-80%
