identify factors affecting maximal performance
provide evidence for and against the central nervous system being a site of fatigue
for
- would impact fatigue if there were a reduction in the number of functioning motor units involved in the activity
- a reduction in motor firsting frequency
against
- study showed that after fatigue electrical stimulus would not imrpove contraction therefor peripheral fatigue only
- - would impact fatigue if there were a reduction in the number of functioning motor units involved in the activity
- would impact if a reduction in motor firsting frequency
identify potential neural factors in the periphery that may be linked to fatigue
explain the role of cross-bridge cycling in fatigue
the cross-bridge’s ability to “cycle” is important in continues tension developoment. fatigue may be related, in part, to the effect of a high H+ concetration and the inability of the sacroplasmic reticulum to reapidly take up Ca++. the end result may be a lpnger relation time, which affects the rate of muscle contraction.
summarize the evidence on the order of recuirmnet of muscle fibres with increasing intensities of activity and the type of metabolism upon which each is dependant
describe the factors limiting performance in all-out activities lasting less than ten seconds
describe the factors limiting performance in all-out activities lasting 10-180 seconds
discuss the subtle changes in the factors affecting optimal personacnes as the duration of a maximal performance increases from three minutes to four hours
central fatigue
brain and spinal cord fatigue
peripheral fatigue
peripheral nerve, muscle sacrolema, transverse tubular system, Ca++ release, actin-myosin interaction, cross-bridge tension + heat, force/power output
free radicals
molecules that contain an unpaired electron in their outer orbital, this unpaired electron relsuts in molesrruvlsr in stability therefore highly reactive and capable of damaging protein, lipids and DNA
list the factors influencing the performance?
Is the limiting factor for strength development located in the CNS or out in the periphery? Support your position.
Tracing the path the action potential takes from the time it leaves the motor end plate, where might the “weak link” be in the mechanisms coupling excitation to contraction?
When fatigue occurs, ATP is still present in the cell. What is the explanation for this?
Describe the pattern of recruitment of muscle fiber types during aerobic activities of progressively greater intensity.
As the duration of a maximal effort increases from 10 seconds or less to between 10 and 180 seconds, what factor becomes limiting in terms of energy production?
Draw a diagram of the factors limiting maximal running performances of 1500 m to 5 km.
Although a high VO2 max is essential to world-class performance, what role does running economy play in a winning performance?
Given that lactate accumulation will adversely affect endurance, what test might be an indicator of maximal sustained running (swimming, cycling) speed?
What is the role of environmental factors, such as altitude and heat, in very long-distance performances lasting one to four hours?
fatigue.
inability to maintain power and force output during repeated muscle contractions which is reversible with rest
antioxidants
molecules that come into contact with free radicals and stabilize the unpaired electrons
how does intensity influence performance and fatigue
