Applied Sport Flashcards
Define SIADH
Syndrome of inappropriate anti-diuretic hormone secretion
Describe what changes to extracellular fluid (ECF) concentration and volume during exercise-induced dehydration
Increase in osmolality (concentration) in ECF
Limited change in volume as fluid moves from ICF to ECF
What are normal sodium and potassium concentrations in ICF and ECF?
ECF sodium = 135-145 mmol/L
ECF potassium = 4.5-5.5 mmol/L
ICF sodium = ~5 mmolL
ICF potassium = ~150-170 mmolL
Does a higher sweat loss rate increase or decrease sweat sodium concentration, and why?
Increase
Sodium reabsorbed by sweat in gland duct
Higher sweat loss rate, LESS TRANSIT TIME FOR SODIUM REABSORPTION
Which hormones are responsible for glucose homeostasis?
Insulin
Glucagon
How does exercise effect Insulin?
Insulin is reduced
Describe the response of epinephrine to exercise
Epi concentration increases during exercise
IT ACTIVATE HORMONE SENSITIVE TRIGLYVERIDE LIPASE
Discuss the impact of epinephrine on lipid metabolism?
Increase in lipolysis (breakdown of lipids/fat)
Describe the activity profile of team sports
Team sports have an ‘intermittent’ activity profile
The majority of time is spent in low intensity activities
Low intensity periods are interspersed with brief intervals of high-intensity activity
Explain the impact and relvance of the concurrent training effect on team sport athletes.
Strength response to training is reduced due to the involvement in high intensity endurance training
This is relevant to team sports because most sports require a combination of strength and endurance abilities
Describe how an increase in muscle capilliarisation affects a-vO2 difference
Increased capillary density in muscle
Increase in mean transit time
Maintanence of a-vO2 difference even at high intensity
How does training in a muscle gylcogen depleted state improve endurance performance?
Results in enhanced mobalisation of fatty acids for fuel
Results in enhanced utilisation of fatty acids for fuel
Spare gylcogen = deferred accumulation of waste products associated with glycolysis
What is the duration (weeks) the acute and chronic ratio are calculated from (Gabbett, 2016 BJSM)?
Acute = 1 week Chronic = 4 weeks
What is an appropriate acute chronic ratio (range) for team sport athletes (Gabbett, 2016 BJSM)?
- 8
1. 3 or 1.5
Identify two objective internal measures to monitor training intensity during exercise
Heart Rate
Blood Lactate
Identify two objective training load variable used to monitor training intensity from GPS
High-speed running (HSR) Relative distance (n/min)
Report three ways of measuring post exercise fatigue
Biomechanical
Neuromuscular
Hormone/endocrine
Perceptual
Why is creatine kinase used as an indirect marker of muscle damage?
CK is found in cells
Low circulating levels of CK in the blood
Following muscle damage CK leaks from cells and is found in blood
Report two common tests of lower body neuromuscualr function
Counter movement jump (or any jump)
Cycle Ergometer
Sprint
Describe three potential causes of transient (short-term) fatigue?
Acidosis
Substrate depletion
Electrolyte depletion
Dehydration
Why does acidosis as a result of high intensity exercise cause athletes to slow down?
Lacti acid causes a proton (H+) to be released which decreases pH
Decrease in pH inhibits PFK, which is a rate limiting enzyme of glycolysis
Decrease in pH inhibits Ca+ release which affects muscle contraction
Blood volume can increase following steady intensity long distance endurance training. What are the mechanisms that cause an increase in maximal cardiac output following this increase in blood volume?
Increase in blood volume results in an increase in end diastolic volume (EDV)
An increase in EDV results in an increase in stroke volume (SV)
Therefore, since heart rate maximum will not have changed, maximum cardiac output will increase as Qmax=SVxHRmax
You invesitgate the effect of sprint training intervention on phosphofructokinase activity (PFK).Explain the effects of training on PFK enzym activity, and how changes to PFK enzyme activity will affect metabolism and sprint performance
PFK ctivity increases
ALLOWS GREATER GLYCOLYTIC FLUX AND ATP RESYNTHESIS FROM MUSCLE GLYCOGEN
Higher power outputs are sustained for a longer period of time
Between 10 and 20s of a maximal sprint, why does the anaerobic contribution to ATP production fall by 50% yt power output only falls by 30%?
The decline in ATP re-synthesis is due to reduced reliance on PCr and anaerobic glycolysis
To compensate, VO2 and oxidative phosphorylation increases
Increased ATP re-synthesis by oxidative phosphorylation (aerobic pathways) offers a partial compensation for the decline in anaerobic ATP re-synthesis
With reference to PCr, why should sprinters avoid training their 100m sprint using short (<5 min) recovery periods?
The 10s will drop PCr content by >50-75%
To reach 100% sprint capacity, this will take longer than 5 min to re-synthesise
Complete PCr recovery could take 13 min or more
Masssage therapy has shown to have no effet on skeletal muscle blood flow. However, what does massage therapy do to promote skeletal muscle adaptation?
Activates mechanotransduction signalling cascade
Accumulation of PGC1apha in the cell nucleus
This leads to stimulation of mitochondrial biogenesis
Massage therapy may also be anti-inflammatory. What is the mechanism?
Massage reduced inflammation; notable reducation in TNFalpha and IL6
Definition of Energy
The property of matter and radiation WHICH MANIFESTS AS A CAPACITY TO PERFORM WORK
What is ATP Utilisation?
ATP + H20 = ADP + H+ + Pi + 31kJ
What is myofibrilar ATPase?
Enzyme that catalyses ATP utilisation
What is the fate of pyruvate?
NADH has extra proton from glycolysis to create lactate
lactate buffers fatigue
Other aspects of the endurance athlete
Nutritional: high CHO% Endogenous CHO are limiting ~ 2hours CHO absorption = >60g Environmental Dehydration of ~2-3% reduces performance
What is VO2max?
Max rate of ATP generation and provides upper ceiling for performance
VO2max = Qmax x a-v (O2)max
Q=SVxHRmax
What is lactic acid?
Lactate is fuel: product of anaerobic glycolysis
1:1 ration of lactate to H+
Increase H+ ions= decrease pH = inhibit PFK and inhibt Ca2+ (muscle contraction)
Lactate Threshold defintions
Baseline ~1 mmol/L
LT1 = increase in Bla above baseline
LT2 = Bla increases exponentially
What is polarized training?
75-80% in easy zone
What is threshold training?
completed between LT1 and LT2
What are the different cycles?
Microcyles: small collection of training
Mesocycles: 3-4 weeks in length (including recovery) re-test at the end of each mesocycle
Macrocycle: overall cycle leads to performance goal, 1/2 year to a year
When the gains dry up….
Block periodisation: join together things that do the same job
CHO periodisation: alongside macrocycle
Alltitude training: increased haematrocirt
What is the Western Blot Analysis?
electric current pulls protein down through gel (lightest at the bottom)
trapped proteins transfered to membrane
membrane is incubated with primary antibodies, then secondary antibodies
enhanced chemilumminescence allows visualisation of proteins
Blunted Myofibrillar protein rates
1 min rest period between sets blunts the early anabolic response to resistance training
resistance exercise bout increase myofibrillar FSR in 1 min and 5 min passive rest (significantly higher with 5 min)
MacDougall Findings
No change in total phosphorylase or LDH
PFK: regulates/ controls speed of flux increase - faster rate of glycolysis = increased ATP
Causes of fatigue?
failure to supply oxygen failure to keep lactate levels down failure to keep phosphate or hydrogen ion levels down failure to lose heat delpletion of fuel source
What is central fatigue?
depletion of brain glycogen, and disturbances in brain neurotransmitters
What is peripheral fatigue?
depletion of subtances and the accumulation of metabolites
Feedback from fatigue - sensitive muscle afferents
What is pacing?
The distribution of work rate throughout an exercise bout and largely influence the success/failure of the performance
Should we avoid faitgue?
No because no fatigue = no stimulus big enough to distrupt homeostasis
Balance of fatigue so athlete can cope with training
What are the adaptations to contractile demands?
Acute bouts of exercise = large/rapid increase in MRNA, returns to baseline after 24hrs, traim frequently to maintain protein levels
Skeletal muscle needs time to make adaptations
