TRAINING PERFORMANCE Flashcards
What is training overload?
Training effect occurs when a system is exercised at a level beyond which it is normally accustomed
What is training specificity?
Training effect is specific to:
Muscle fibers recruited during exercise.
Energy system involved (aerobic versus anaerobic).
Velocity of contraction.
Type of contraction (eccentric, concentric, isometric).
What is training reversibility?
Gains are lost when overload is removed
Research Designs to Study Training?
Cross-sectional studies
Longitudinal studies
What are the Cross-sectional studies of training?
Examine groups of differing physical activity at one time
Record differences between groups
What are the Longitudinal studies
of training?
Examine groups before and after training
Record changes over time in the groups
How do you perform Training to increase VO2 max?
Large muscle groups, dynamic activity
20–60 min, 3–5 times/week, 50–85% VO2 max
Intervals: 2-5 min, 95%, x 8-10 repeats
When training what are the Expected increases in VO2 max?
Average = 15 - 20%
2–3% in those with high initial VO2 max
Requires intensity of 95–100% VO2 max
30–50% in those with low initial VO2 max
Training intensity of 40–70% VO2 max
What is the genetic predisposition to increasing VO2 max?
Accounts for 40%–66% VO2 max
Prerequisite for VO2 max of 60–80 mLkg–1min–1
What is The HERITAGE Family Study?
Designed to study the role of genotype in cardiovascular, metabolic, and hormonal responses to exercise and training
What were the results of The HERITAGE Family Study?
Heritability of VO2 max is ~50%
Maternal contribution is ~30%
Large variation in change in VO2 max with training
Average improvement 15–20%
Ranged from slight decrease to 1 L/min increase
Heritability of change in VO2 max is 47%
Difference genes for sedentary VO2 max and change in VO2 max with training
What is the Product of maximal cardiac output and arteriovenous difference (Fick Equation)?
VO2 max = HR max x SV max x (a-vO2) max
What are the Differences in VO2 max in different populations?
Primarily due to differences in SV max
What are the Improvements in VO2 max?
50% due to (up arrow) SV (central component)
50% due to (up arrow) a-vO2 (peripheral component)
Factors Increasing Stroke Volume?
Increased stroke volume
Increased end diastolic volume (“pre-load”)
Increased contractility
Increased plasma volume
Increased filling time and venous return
Increased ventricular volume
Decreased peripheral resistance (“afterload”)
What is stroke volume?
Increased maximal stroke volume
increased Preload (EDV)
increased Plasma volume
increased Venous return
increased Ventricular volume
decreased Afterload (TPR)
decreased Arterial constriction
increased Maximal muscle blood flow with no change in mean arterial pressure
increased Contractility
Changes occur rapidly in stroke volume when?
11% ↑ in plasma volume, 7% ↑ VO2 max, and 10% ↑ in stroke volume within first six days of endurance training.
Why Do Some Individuals Have High VO2 Max Values Without Training?
Some individuals have very high VO2 max values with no history of training
VO2 max = 65.3 mlkg–1min–1
Compared to 46.3 mlkg–1min–1 in sedentary with low VO2 max
Higher VO2 max is due to?
Higher maximal cardiac output, stroke volume, and lower total peripheral resistance
No difference in a-vO2 difference or maximal heart rate
Higher stroke volume linked to?
Higher blood volume and red cell volume
Arteriovenous O2 Difference?
increased Muscle blood flow
decreased SNS vasoconstriction
Improved ability of the muscle to extract oxygen from the blood causes?
increased Capillary density
increased Mitochondial number
Improved ability of the muscle to extract oxygen from the blood causes?
increased Capillary density
increased Mitochondial number
Explain The a-vO2 diff—Arterial O2 Content?
Hemoglobin (Hb)—1 molecule of Hb carries 4 molecules of O2, and 100 ml of blood contains ~14-18 g of Hb in men and ~12-14 in women (1 g of Hb combines with 1.34 ml of oxygen).
There are ~20.1 ml of O2 per 100 ml of arterial blood (15 g of Hb 1.34 ml of O2/g of Hb) in men and ~17.4 ml of O2 per 100 ml of arterial blood (13 g x 1.34) in women.
Low iron leads to iron-deficiency anemia, reducing the body’s capacity to transport oxygen—this is more of a problem in women than men.
The ability to perform prolonged, submaximal exercise is dependent on the ability to maintain homeostasis, how is this possible?
Endurance exercise training results in numerous adaptations in muscle fibers that assist in maintaining homeostasis.
Shift in muscle fiber type (fast-to-slow) and increased number of capillaries.
Increased mitochondrial volume.
Training-induced changes in fuel utilization.
Increased antioxidant capacity.
Improved acid-base regulation.
What happens during a Fast-to-slow shift in muscle fiber type?
Reduction in fast fibers and increase in number of slow fibers.
Magnitude of fiber type change determined by duration of training, type of training, and genetics.
Increased number of capillaries surrounding muscle fibers causess?
Enhanced diffusion of oxygen.
Improved removal of wastes.
How does endurance training increases the volume of both subsarcolemmal and intermyofibrillar mitochondria in muscle fibers?
Results in improved oxidative capacity and ability to utilize fat as fuel.
Training also increases mitochondrial turnover (that is, breakdown of damaged mitochondria and replacement with healthy mitochondria).
Breakdown of damaged mitochondrial is termed “mitophagy.”
What is the Significance of Increased Mitochondrial Volume?
Increased mitochondrial volume results in greater capacity for oxidative phosphorylation.
However, during submaximal exercise, the steady-state VO2 is not influenced by endurance training.
Increased mitochondrial volume also decreases cytosolic [ADP] due to increased ADP transporters in mitochondrial membrane-results in:
Less lactate and H+ formation.
Less PC depletion.
What is the Influence of Mitochondrial Volume on Cytosolic ADP Concentration during Submaximal Exercise?
Increases in the number of ADP transporters in mitochondrial membrane = faster ADP uptake into mitochondria and lower cytosolic [ADP]
What is Citrate synthase (CS)?
Marker of mitochondrial oxidative capacity
What is the effect of exercise intensity with Citrate synthase (CS)?
55%, 65%, or 75% VO2 max
Increased CS in oxidative (IIa) fibers with all training intensities