Skeletal System
What are the two types of bone tissue found in the skeletal system?
What is: Cortical & trabecular
What is the functional unit of a muscle fiber?
What is: Sarcomere
What type of muscle contraction occurs when a muscle lengthens while under tension?
What is: Eccentric Contraction
What principle refers to training specific to the desired goal, such as power or endurance?
What is: Specificity
What is the primary neurotransmitter released at the neuromuscular junction?
What is: Acetylcholine or ACh
What term describes the primary process of bone cell turnover?
What is: Remodeling
Which hormone decreases blood calcium levels by promoting bone deposition?
What is: Calcitonin
Which protein anchors myosin filaments in the middle of the sarcomere?
What is: Myomesin
Which two neural factors influence force production in muscles?
What is:
(1) Rate Coding (Frequency of stimulation)
(2) Motor Unit Recruitment
What is the recommended frequency of resistance training for health benefits according to ACSM guidelines?
What is: at least 2-3 days per week
Which proprioceptor detects changes in muscle length and triggers the stretch reflex?
What is: Muscle Spindle
What is the name of the neurotransmitter that initiates action potentials in muscle cells?
What is: Acetylcholine
What is the minimal effective strain (MES) required for bone adaptation?
What is: 2.5 x Body Weight
What regulatory protein binds calcium during muscle contraction?
What is: Troponin
What happens to the H-zone during muscle contraction?
What is:
It shortens or disappears as the sarcomere contracts
Name the three neuromuscular adaptations to resistance training.
What is:
(1) increased motor unit recruitment
(2) synchronization
(3) rate coding
What is the primary function of gamma motor neurons?
What is: They regulate the sensitivity of muscle spindles
What term refers to the minimum stimulus needed to trigger muscle contraction?
What is: Threshold Stimulus
What percentage of peak bone mass is typically achieved by age 20?
What is: 95%
According to the all-or-none principle, how does a motor unit respond to a threshold stimulus?
What is: It contracts to its fullest extent
What is the relationship between force and velocity in muscle contraction?
What is:
As force increases, shortening velocity decreases
Which fiber type is associated with high power and fast contraction speed?
What is:
Type IIx fibers
What is the role of the vestibular apparatus in movement control?
What is: It maintains equilibrium and adjusts muscle tone for balance
Which muscle fiber type is most fatigue-resistant?
What is: Type I of SO Fibers
Name the diagnostic method that measures volumetric bone mineral density in both trabecular and cortical bone.
What is the role of titin in muscle contraction? (3)
What is:
(1) It acts as a molecular spring
(2) stores elastic energy
(3) contributes to residual force enhancement.
What are the four phases of the cross-bridge cycle?
What is:
(1) Binding
(2) power stroke
(3) dissociation
(4) activation
How does the principle of overload apply to resistance training, and what are two key variables to manipulate for overload?
What is:
Overload requires progressively increasing the training stress to stimulate adaptations.
Key variables include intensity (weight lifted) and volume (reps/sets)
Explain the inverse myotatic reflex.
What is:
It inhibits muscle contraction in response to excessive tension detected by Golgi tendon organs.
Name the diagnostic method that measures 3D microarchitecture of bones
What is:
High-resolution peripheral Quantitative Tomography or HR-pQCT