LOCK IN BRO Flashcards
(122 cards)
On a dual-energy X-ray absorptiometry (DXA) scan, how are osteopenia and osteoporosis defined in terms of T-score ranges?
- Osteopenia: T-score between −1.0 and −2.5 SD below the young-adult mean.
- Osteoporosis: T-score ≤ −2.5 SD below the young-adult mean.
How does heavy resistance training affect tendon mechanical properties—does it make tendons more elastic or stiffer?
Tendons become stiffer (↑ modulus and stiffness, ↓ compliance); elasticity does not increase.
What happens to muscle pennation angle after several weeks of heavy resistance training? How does this change effect force production?
It increases - larger fascicle-to-tendon angle allows more fibers in parallel, enhancing force.
Does the density of Sarcoplasmic reticulum and T-tubules (plus general cytoplasmic volume) increase or decrease in response to heavy resistance training, improving calcium handling?
Increases
Which regulatory protein does calcium bind to in skeletal muscle to initiate contraction?
Troponin C (the Ca²⁺-binding subunit of the troponin complex)
After Ca²⁺ binds troponin, what happens to tropomyosin?
Tropomyosin shifts away from the actin active sites, exposing them for myosin attachment.
During the power stroke, actin filaments slide toward which part of the sarcomere?
Toward the M-line (center), shortening the sarcomere.
What immediate role does acetylcholine play in muscle contraction? Does it bind to troponin?
It binds nicotinic receptors at the neuromuscular junction, triggering the sarcolemma action potential that ultimately releases Ca²⁺—it does not bind troponin/tropomyosin.
What quantity of carbohydrate is recommended per hour before a match for team-sport athletes?
About 35 g of carbohydrate for every hour remaining before the start (e.g., 35 g at 1 h, 70 g at 2 h).
True or False: Protein (10–20 g) is advisable within 2 h of competition
False. Protein is generally kept ≥ 3 h away; 10–20 g protein is recommended in the pre-event meal ≈ 4 h before start time.
Why are high-fat or protein-rich foods discouraged in the last 3 h before competition?
They slow gastric emptying and may cause GI distress, potentially impairing high-intensity performance.
What is the primary route by which blood lactate is removed during and after exercise? Where does it go after it exits?
Oxidation to pyruvate in type I skeletal muscle fibers and cardiac muscle, followed by entry into the Krebs cycle.
True or False: Lactate is “reduced” to pyruvate during clearance.
False. Lactate is oxidized (loses electrons) to form pyruvate.
What is the role of the liver in lactate clearance during prolonged recovery (Cori cycle)?
The liver converts some lactate to glucose via gluconeogenesis, but this accounts for only ~15-20 % of lactate disposal during active recovery.
Why doesn’t blood lactate drop above the lactate threshold even though the body can use lactate for ATP?
Production outpaces oxidation; lactate accumulates faster than it can be shuttled and oxidized, so it is not “turned into ATP” fast enough to prevent buildup.
Are omega-3 and omega-6 fatty acids poly- or mono-unsaturated fats?
Polyunsaturated fatty acids (PUFAs).
Why are omega-3 (α-linolenic acid) and omega-6 (linoleic acid) called “essential” fats?
The human body cannot synthesize them; they must be obtained in the diet for normal growth, brain development, and eicosanoid (hormone-like) synthesis.
List two physiological roles shared by omega-3 and omega-6 fatty acids.
- Neural and retinal development / brain function
- Precursor for hormone-like eicosanoids (e.g., prostaglandins, leukotrienes)
Name a common dietary source rich in omega-3 fatty acids.
Fatty cold-water fish (e.g., salmon, mackerel, sardines) or flaxseed/ALA-fortified products.
Name a common dietary source rich in omega-6 fatty acids.
Plant oils such as soybean, corn, and safflower oil.
For athletes with low skill or limited experience, is the optimal arousal level generally higher or lower?
Lower—they perform best with less physiological and cognitive activation.
According to the inverted-U hypothesis, how does optimal arousal shift as skill level increases?
The curve shifts rightward: highly skilled athletes tolerate (and often need) higher arousal before performance declines.
Give one reason why complex, fine-motor tasks (e.g., quarterback decision-making) require lower arousal than simple power tasks.
Excess arousal increases muscle tension and narrows attentional focus, disrupting coordination and decision speed in complex skills.
Name two techniques a rookie quarterback could use minutes before play to reach a lower-than-normal arousal state.
- Diaphragmatic breathing
- Progressive muscle relaxation (or cue-controlled centering).
