Exam 2 Flashcards
A central component of fatigue is that it is ALWAYS _______________.
Reversible with rest
True or false. Different muscles in the body fatigue at different rates during exercise.
True
True or false. The warmer the weather, the longer a person can exercise until reaching exhaustion/fatigue during physical activity.
False
When taking skinfolds, we assume that all body tissue is either fat mass or fat free mass (i.e., Mass = FM + FFM). This is called the _____________
Two-compartment model
Which type of tissue is more dense?
Fat free mass
Which body composition method relies on Archimedes principle?
Underwater weighing
Approximately what % of US adults are overweight or obese?
70%
Which of the following body composition techniques does NOT first determine body density in order to predict % fat?
Bioelectrical impedance analysis
Which of the following body composition methods can assess bone mass?
Duel-Energy X-Ray Absorptiometry (DEXA)
True or false. There is not a one-size-fits-all optimal body composition for sport performance. In other words, an optimal body composition for one sport may not be the optimal body composition for a different sport.
True
Calcium is stored in the _______, to be released to start muscle contraction.
Sarcoplasmic reticulum
The ends of a sarcomere are called the ______.
Z-discs
In the resting state, ________ blocks the myosin binding sites on actin to prevent muscle contraction.
Tropomyosin
True or false. The shortening of actin and myosin during cross bridge cycling results in the sarcomere shortening, which in turn results in muscle contraction.
False
Action potentials are able to transmitted across the neuromuscular junction due to the action of the neurotransmitter ___________.
Acetylcholine (ACh)
ATP is needed during what part of muscle contraction?
Allowing myosin head to release from the actin.
Stains darkest when determining muscle fiber type
Type I
Highest resistance to fatigue
Type I
Largest motor units
Type IIx
Highest oxidative capacity
Type I
Causes of Fatigue
- Inadequate energy delivery/metabolism
- Accumulation of metabolic by-products
- Muscle activation influence
Define obese in terms of BMI.
30+ BMI
Define overweight in terms of BMI.
25-29.9 BMI
Define the normal BMI range.
18.5-24.9 BMI
BMI equation
kg/m^2
Body density equation
D= (BW) / [(BW-UWW-RV)/DH20]
Archimedes Principle
What are Siri calculations used for?
Calculating %fat when body density is known. (Skin folds)
Underwater weighing pros and cons.
Pros: 2-3% error, inexpensive, not affected by pretest protocol (Gold Standard)
Cons: Uncomfortable, estimate RV
Bod Pod pros and cons.
Pros: 2-3% error (from UWW), more comfortable
Cons: Expensive, relies on pretest protocol
DEXA pros and cons.
Pros: 1-2% error (from UWW), 3 component model, regional BC, pre-test is less important
Cons: Radiation exposure, expensive, not field based, requires technical expertise, cannot use with metal implants
Bioelectrical Impedance Analysis (BIA) pros and cons.
Pros: Easy and quick, field based, 3-4% error from UWW
Cons: Tests only part of body, no regional BC, hydration status heavily affects error
Define android and gynoid body types.
Android is apple shaped. Gynoid is pear shaped. Gynoid causes less health complications due to less fat near the vital organs.
Recommended micronutrient balance
Carb: 55-60% of daily kcals
Fat: <35%
Protein: 10-15%
Recommended carb intake during exercise.
20-25g of high GI food/drink of carbs every 30-45 min.
True or false. It is possible to produce more force during a maximal eccentric contraction than a maximal concentric contraction.
False
When picking up a water bottle from the table, what type of muscle fibers will supply the force needed to accomplish this task?
Type I
ACSM’s recommendations for resistance training/muscle strengthening exercise:
- 2+ days/week non-consecutive
- All major muscle groups
- Exercises, sets, and reps dependent on training experience and goals
Archimedes principle
Archimedes principle: A person in water displaces a certain amount of water which bouys them upward (making them lighter). By assessing weight out of water and weight in water, it’s possible to determine a person’s body volume, which can be used to calculate body density (D=M/V), which can then be converted to a %fat.
Advantages and disadvantages of hydrostatic weighing
Advantages:
Inexpensive (costs less than many other BC measurement tools)
Accurate (2-3% error)
Disadvantages:
Uncomfortable (subject needs to get wet and let air out before going underwater)
Cannot be used as a field test (other models such as BIA can be done relatively anywhere)
Plyometric training utilizes the ________ reflex to increase the force of muscle contraction
Muscle spindle
Which of the following does not rely on densitometry for body composition assessment?
BIA
True or false. Toya experiences DOMS following a high-intensity workout. While DOMS is painful, it will not acutely lower the maximal force generation of the muscles with DOMS.
False
Which of the measures will be heavily influenced by hydration status?
BIA
True or false. Heavenly and Quad both consume 60 g of carbohydrate in a recovery drink following exercise, but Heavenly consumes her drink 15 minutes after exercise and Quad consumes her drink 4 hours after exercise. These two women will likely have the same level of glycogen resynthesis from the recovery drink.
False
True or false. Pennated muscles can produce more force than parallel muscle fibers of the same size.
True
Toya, a 65 kg female powerlifter, comes to our lab with questions about nutrition. What is the most protein you would recommend for her based on recommended intakes discussed in class?
110g
Which of the following is the only true gold standard measure of body composition?
Underwater weighing
Which of the following body composition methods does NOT rely on the 2-compartment model?
DEXA
Risk of DOMS is higher with exercise involving eccentric contractions compared to exercise involving and concentric contractions.
True
Santa Claus wakes up in the morning and immediately does a workout before breakfast. He finds that he fatigues more quickly than on days where he works out 2-3 hours after lunch. What is the most likely mechanism contributing to greater fatigue in his morning workout?
Inadequate energy delivery
What is the difference between fatigue and injury?
Fatigue is reversible with rest, whereas injury is not
Donald (90 kg) and Bugs (70 kg) are walking together at 2.5 mph. Both have a VO2 of 1.5 L/min. In relative terms, who is more economical during the walk?
Donald
Aerobic training causes a(n) ____________ shift in lactate threshold, allowing individuals to exercise at a higher intensity before accumulating lactic acid in the blood.
Right
