Physiology of middle distance events Flashcards
At what percentage of VO2 max are middle distance events generally completed at
95-100%
explain the energy cost of running a 4 minute mile
would require a VO2 max of 80-85 ml/kg/min
elite athletes generally have a VO2 max of around 70
therefore aerobic processes will not be sufficient to meet the demands of the run
an oxygen deficit will be created (the area above the curve)
roughly how long does it take for a person to reach their VO2 max and what is the implication of this
2-3 minutes
means that in the early part of the race there will be a large energy deficit if relying just on anaerobic processes
what evidence is there that there is a high anaerobic contribution in the early stages of a race
depleation of creatine phosphate
production of lactic acid
what are the overall energy contributions to the running of a middle distance race
0-30 seconds = 75% anaerobic (time delay of switch on of aerobic)
30-60 seconds = 50% each, ox. phos. now switched on
60-end = increasing contribution of aerobic due to increasing rate of ox. phos. being able to meet more of the demand
overall = 60% aerobic
what are the 4 determinants of performance in middle distance events
VO2 max
running econonmy
vVO2 max
T lim
define vVO2 max
which two other factors combine to determine vVO2 max
the running velocity at which a runner achieves their VO2max
it is a product of VO2 max and running economy
define Tlim
explain what is infered by a greater Tlim
the maximal amount of time which a runner can sustain their vVO2 max for
a bigger anaerobic capacity because the longer you run at VO2 max the more of an oxygen deficit you create
what is considered to be the limit to performance in middle distance events
Anaerobic capacity (these determine the vVO2 max)
specifically H ions and Na/K pumps
ouline the methods and findings of the trial into the best way to improve VO2 max for middle distance events
continuous vs HIIT training
30 mins constant work at 50% VO2 max
30 seconds off 30 on at 100% VO2 max
statistically significant increase in VO2 max with HIIT, not seen with continuous training
offer some critique of the work on training interventions to improve VO2 max
VO2 max values published were relativly low so may not see the same benefits in elite athletes
short intervals and regular breaks probs meant VO2 max wasn’t reached so may have got more benefit if altered to reach VO2 max sooner
outline the methods and findings of the trial into the best way to improve time spent running at VO2 max
continuous group vs interval group
continuous ran at a speed half way between LT and VO2max until fatigue occured
interval group ran for 30 secs at 100% vVO2 max and 30 seconds at 50% vVO2 max
interval group spent longer at VO2 max
1 session per week saw marginal increases in VO2 max and significant increases in vVO2 max
findings have been validated by other studies
similar studies also demonstrated a resulting improvement in 300m times
outline the methods and findings of the study into training to improve aerobic capacity
8 week trial
single leg knee extension at 150% thigh VO2 max
15 x 1 min intervals with 3 minute rest
post training thigh muscle was able to achieve a higher VO2
muscles also had increase citrate synthase and glycogen
similar trials have shown greater time to fatigue and less time to perform a given amount of work vs controls
outline the methods and findings of the study into improving anaerobic capacity
same 8 week knee extension intervention
increased the amount of workload achieved and the time to fatigue
at submax intensities there was a reduction in lactate production (increased lactate threshold)
at maximal intensities there was an increase in lactate production (able to produce more lactate so increase in anaerobic function)
what are the potential problems with increasing an atheletes anaerobic capacity
will increase the production of fatigue causing metabolites e.g H
no use if the body is unable to tollerate these
what has been the overall findings from trials investigating the potential for training to improve buffering capacity
mixed findings
but these variables are hard to measure so this may be why
what is the function of the MCT protein and how does it work
to remove lactate from cells
lactate and dissociated H bind, ATP utalised to remove them to the outer side of the cell
outline the methods and findings of the trial into training to improve lactate and H transport
same 8 week knee extensor intervention
increased amounts of MCT1 and MCT4
representing and increased ability to transport fatigue causing metabolites
outline the evidence to support doing a warm up at higher intensities than normal to enhance middle distance performance
normal warm up vs warm up at 90% CP
90% saw 1 min increase in time trial to exhaustion
also saw a decreased VO2 slow component and a decreased O2 deficit
similar protocol used by Jess Ennis in London 2012 and ran a PB for 800m
give the key points from the reading from the paper on the high intensity warm up
overall speeding up of the VO2 kinetics
this would attenuate the reduction in Pcr and decrease accumilation of fatigue causing metabolites e.g h
during trials total VO2 used was greater so greater contribution of total energy utalisation from aerobic sources
more aerobic + same full use of anaerobic = greater total energy yield
