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Preparation / Rehearsal Sprints Pre Competition / Training By John Anderson Update your preparation exercises and move into the 21st Century Why bother ?! Do we need warm-up ? If we do, What do we want it for? How do we use it? Does it work? Benefits of Appropriate Preparation Performance can be improved by an appropriate preparation Increases speed of contraction and relaxation of warmed muscles. Dynamic exercise reduces muscle stiffness. Greater economy of movement because of lowered viscous resistance within warmed muscles. Facilitates oxygen utilisation by warmed muscles because haemoglobin releases oxygen more readily at higher muscle temperatures. Facilitates nerve transmission & muscle metabolism at higher temperatures; a specific warm up can facilitate motor unit recruitment required in subsequent all out activity. Allows the heart rate to get to a workable rate for beginning exercise. Mentally focuses on the training or competition. Challenge standard thinking !! Extensive search in libraries – no internet !! 1968 No scientific evidence that passive stretching was beneficial. Don Halliday, 100m 1972 Olympic Games used as guinea pig !! Research and Empirical Evidence This shows overwhelmingly that Passive stretching -:Does not prevent injuries Does not influence the seriousness of the injury. Does not cause injury to heal quicker. In other words, passive stretching has no effect on the incidence or the prevention of injury. The Stretch Reflex This is the reflex contraction of a muscle when it is stretched. Special sensory cells, called proprioceptors, monitor the state of muscles The stretch reflex protects a muscle from being over-stretched and damaged. Important ---- this protective mechanism can itself be damaging if a muscle is lengthened suddenly, especially when cold. A muscle will automatically and forcibly try to shorten, sometimes rupturing itself !!!!! Reference : The Oxford Dictionary of Sports Science and Medicine Research on Stretching cont Passive stretching will result in a decrease in the force generating capacity of a tendon - -- lasting in some cases 60 mins !! This has a negative influence on performance for those activities which require high force levels. e.g.. Sprinting. The protective mechanism (stretch reflex) can itself be damaging if the muscle is lengthened suddenly especially when cold. The muscle will automatically and forcibly try to shorten even to the extent of rupturing itself. Long Term Adaptations Some of the perceived gain in ROM following a stretch could actually be due to stretch tolerance, presumably from desensitising of proprioceptors. This brings question marks to the theoretical effectiveness of stretching to alter ROM and also raises safety concerns. Could stretch tolerance inhibit stretch reflex and allow damage to occur to antagonist muscle tendon units (MTU’s) and joint structures? Rehearsal / Specificity ROM (range of movement) is crucial to good performance. In sprinting this allows the application of force. Eg the foot against the ground, to be applied much more efficiently and thus bio mechanically more effective. The most effective method of achieving optimum ROM is by the process of repetition and specificity – practice running fast !!!! References for the previous points Research based evidence as to why dynamic warm ups are potentially an improvement to static warm ups can be found in the Journal of Strength and Conditioning Research by McMillan et al – the Effect on Power and Agility Performance. Herbert and Gabriel, University of Sydney, (BMJ August 2003). Benefits of Cool Down Aids in the dissipation of waste products, including lactic acid. Reduces the potential for DOMS Reduces the chance of dizziness or fainting caused by the pooling of venous blood at the extremities. Reduces the level of adrenaline in the blood Allows the heart rate to return to its resting state. GENERAL PREPARATION Gentle start to activate the body Walk or jog 30 – 60 m x 2 – 3 Variations of walking – High knees, high on toes over 30m x 2 - 3 Jogging with high knee raise x 2 -3 General exercises Spinners Scorpion Crab Leg Swings Specific Rehearsal for Sprinting 30 – 60m @ half speed x 2 – 4 30 – 60m @ ¾ speed x 2 – 4 30 – 60m flat out x 1 – 3 Sprint Start – flat out, 30 – 40m x 1 - 3 PB !!!!!!