Where speeds may exceed 60 kmph
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I chose the Keirin sprint as the event for my PD/H/PE assessment. Basically the task asks for the major energy systems used, the types of training needed, the mental preparations strategies/theories, and the nutritional needs and requirements.
For the energy systems, I would say its mainly the lactic and the alactacid systems. The sprint begins with the alactacid system as the rider needs an instant burst for launch. Then after the initial 10-12 seconds, the creatine phosphate stores run out, then the body switches over to the lactic acid system. It then burns glucose for energy. This system should be able to last the approx 2 minutes before the final sprint, as I would say that the 6 laps or so are at medium intensity. Then for the final 2 laps, the creatine phosphate supplies have restored, allowing the alactacid system to kick in again. I dont have any experience of track sprinting, so htis is from what I took as a estimate. WOuld anyone back this up? Or change certain parts that are wrong?
As for training, Ill prob source info from the LIVESTRONG site. But it would be good to get an actual training program from one of your guys.
Mental prep startegies and theories. Track is all about tactics. Anyone care to share some info on how you do it?
Same goes with nutritional needs and requirements. If anyone could provide a personal account, it would help me out a lot.
You actually choose a very tough race as it can play out in many different ways and involves infact all energy systems. It is primarily a sprint event but lasting 8laps (2km) there is an element of endurance. There is 5.5 laps behind the motor bike and apart from the first 2 seconds off the line (fighting for position) this will be endurance pace so it will be (mostly) your aerobic system that provides the energy. However last 2.5 laps is where it gets interesting. Sometimes the sprint doesnt start then, sometimes it does. You will find a lot of 1km TT riders do well at the keirin because it is a longer sprint (around 45 or so seconds if its 2.5 laps) this will involve (mostly) your Lactic Acid system. However sometimes the sprint starts later 1-1.5 laps to go, if this is the case a much larger portion of your energy requirements will come from your ATP-CP system.
Really you can spend a lot of time looking at this and the answer to a large degree will become it depends.
The match sprint or individual pursuit would be much easier to look at.
Well so far Ive only said that Ill be doing track sprinting as my choice. The event I can change, but it will have to still be within track cycling. I initially chose Keirin since its only 2km, thinking that the body wouldnt need to go into the aerobic system.
Anyway, looking at a match sprint, it may actually be easier. Its a 3 lap race. First lap is quite low intensity, then theres the second which picks up the pace, and the third which is pretty much an all out sprint. Would this match sprint be using primarily the lactic acid system? Then for the final lap its the ATP/PC system? However, one thing is, that wouldnt a warm up allow oxygen to fill in the muscles? That means the body starts off with the aerobic then change to ATP/PC at the end, without the lactic acid system?
Anyway, the assessment is a 10 min presentation. With the match print, or individual pursuit, it may be too short for a presentation. But it may be perfect if theres lots to talk about training.
The Keirin as you said is unpredictable, so I may use a visual aid of a 3 min Keirin race from maybe the 2012 Olympics. I can use that as an example, and depending on the final sprint length, I would be able to tell which energy system it is. What do you reckon?
The 2012 world champs was a better race IMO.
It is less about the time and more about the intensity that dictates the energy system remembering they are rarely in isolation. A match sprint the first 2 laps will be mostly aerobic system (cause its low intensity).
The last lap-1.5 laps will be using the ATP-CP probably predominately with lots of input from the lactic acid system.
You mean this one:
So at 4:05 of the vid, there 2.5 laps remaining when they start to increase the intensity a bit. And its in the final lap when they are at almost maximal.
So itll be first few seconds of the ATP/PC system as they fight for position. Then the 5.5 laps from there are at endurance pace so the aerobic system is used. The final 2.5 laps is high intensity for 35 secs, making it mostly the lactic acid system.
The race goes on for about 2.5 minutes. Thats one quarter of my presentation, which Ill cover only the energy systems. The remaining will be on the other three areas which Ill get a start on tmw arvo. WOuld the above info be correct?
EDIT: The more I think about it the more confusing it gets. The cyclists do a warmup before the race, that means they have already gotten oxygen into their muscles. That means they would start off with the aerobic system. The only time that the body switches back to anaerobic is when the muscles do more work than the supplied oxygen. These cyclists have trained so that their systems are effiecient, meaning they may not even switch over to the anaerboic system?
Aerobic metabolism is used in all cycling events, just the proportion of energy demand satisfied by the various energy systems varies.
A kilo TT would be a more consistent study than races like match sprints and keirins that are heavily dependent on race craft as well as physiological conditioning.
The kilo TT taps all energy systems (approx 45:55 energy demand met by aerobic glycolosis to the various combined anaerobic energy pathways, give or take) - and if your talk is mostly about physiological / metabolic pathways, then a kilo is a good choice. It's a brute of an event.
Check out work by Gastin on energy pathways during maximal efforts.
From what Ive learnt, a one minute cycle(1km TT) at maximum intensity would mainly use the lactic system, with the initial start(10-12secs) using the alactic system. This actually may not be enough for a 10 min presentation. But then you say that all three systems are used within this event. I can see how both the anaerobic systems will be used, but not so much the aerobic system. I am only find Gastin's abstract of his work.
That is why I am thinking of using a direct example to explain the energy sytems used. That example would be the 2012 UCI race which I linked above.
Looking onto training, I have been able to find various sources that talk about mainly the anaerobic system being used in track sprints. AS below:
Alexs point was the systems are never used in isolation. Its not like one system switches off and another switches on, from the moment you begin you 1km TT you will be using all 3 systems. It is the percentage of each system that changes over time and intensity of the effort.
The good thing about that keirin race is you can actually talk about how a difference in tactics can lead to different energy system usage, compare the winner (Hoy) to Levy, Levy is on the front for the final 2.5 laps into the wind whereas Hoy uses more of a burst at the end to win it.
I'm not going to weigh in with the experts about energy systems, but if you want a good example of the tactical nature of the keirin, have a look at the 2012 Olympic Women's final. Anna Meares, world keirin champion, jumped pretty much straight after the derny pulled off in response to, I think, the Chinese woman's move. You could see her realise that she had made a mistake and she tried to get her head back together and contest, but she knew she'd lost it with about 2 laps to go and she ended up not even placing. All other things being equal, she was faster than any of the other riders out there, but the mistake cost her a medal.
When watching that race I was yelling at the TV "what are you doing Anna?!!"
It took some excellent psychology to come out and win the sprint after that.
Kilo most definitely uses all energy systems in the actual event, as well there is a role for some aerobic development of a kilo rider, as well as things like body fat management. All the systems are used all the time, we are not light switches.
I can point you to a good presentation regarding Individual Pursuit but you seem more interested in sprint events.
Carl Brewer is a local Aussie coach based in Melbourne that has written a fair bit on sprint events. See here:
http://upupup.aboc.com.au/the-book/01-w ... ing/theory
and he's listed plenty of resources.
There are also plenty of historical information available from Fixed Gear Fever forum.
For some reason sprint coaches generally seem loath to publish their "secret sauce", so it's nice to see someone break the trend. It's not really that complicated, the basic principles of training apply, with the specificity principle paramount.
I said the same thing. I think she did as well.
Any psychological reason why she did that? Pressure from the final race? Loss of focus?
Anyway, I'll stick with the keirin race, but it'll be the Women's final. It's a full 2 lap sprint meaning its using predominantly the lactic acid system, and I can relate it with the Women's final sprint, where Meares won the race, due to some great psychological strategies.
And the riders get onto road bikes soon after getting of their track bike. I am taking this as their cool down? Or would the cool down be the few laps they do as they slow down? Why do they get onto road bikes afterwards?
Probably just a simple mistake caused by nerves. As mentioned, one of the other women jumped and she reacted. Maybe she thought it was Pendleton and needed to follow, I don't think we'll ever know.
As for the road bikes, yes, it's for warm down. Rolling around on doesn't do anything productive, so a proper warm down is important, particularly if you're backing up for another heat. I think they use the road bikes simply to save their track bikes for racing. They have their main bike and a spare or two just in case, so you don't want to use them unnecessarily. If they're using rollers, they can also use the gears on the road bike to step down the effort gradually, i.e. keep their cadence at a set level, but switching up gears to make things easier as they warm down (and the opposite as they move up). I have seen them riding the road bikes around the infield as well, so they may also be using them to take advantage of the brakes in a crowded environment.
Thanks to everyone here for helping out! Training, psychology and nutrition(not much over than post race rehydration) weren't all that bad.
I've completed everything and the presentations will begin tmw, and continue on Tuesday and Wed. Looks like mine will be done first up on Wed, or possibly very last tomorrow.
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