Negative Splits in a race... (Page 4)

amiine - 2008-02-01 3:30 PM

I would apply it down to 20-30 mins event because below that, is very difficult to calibrate the speed: in a track and field, 5k, 1.5k, 3k, etc. are all anaerobic events and negative split looses his meaning. 10k is something in between and tipically I start to apply the concept on this length. >>> huh?!?!? You consider 5K, 3K or even a 1.5K anaerobic events? If you do you need to review your sport physiology text book because they aren’t

Plissken74 - 2008-02-03 11:27 AM Here the discussion can be long but you know very well that I am speaking about amateurs. PROs athletes have different performance in terms of anaerobic and aerobic efforts and, among them, the discussion should be split between different categories of running length. I would bet that 95% of the BT members still run MOSTLY anaerobic in 5k races. They are not optimized for running mostly aerobic in 5k as you assume from phisiology. Of course, here, another assumption is that those BT member should run at the max potential on 5k otherwise they will go again in aerobic effort. Officially, phisiology books state that up to 2 mins intense exercises are anaerobic so, for PRO, it means ca. 800meters. But with lactate test, you can see studies reporting that 30% of the effort is anaerobic in 1500meters too. This 30% dramatically goes down at 3k. For PRO... For you I do not know For me neither since I never did a lactate test.

Plissken74 - 2008-02-03 1:27 PM

Here the discussion can be long but you know very well that I am speaking about amateurs. PROs athletes have different performance in terms of anaerobic and aerobic efforts and, among them, the discussion should be split between different categories of running length. I would bet that 95% of the BT members still run MOSTLY anaerobic in 5k races. They are not optimized for running mostly aerobic in 5k as you assume from phisiology. Of course, here, another assumption is that those BT member should run at the max potential on 5k otherwise they will go again in aerobic effort.

Officially, phisiology books state that up to 2 mins intense exercises are anaerobic so, for PRO, it means ca. 800meters. But with lactate test, you can see studies reporting that 30% of the effort is anaerobic in 1500meters too. This 30% dramatically goes down at 3k. For PRO... For you I do not know For me neither since I never did a lactate test.

bryancd - 2008-02-03 5:24 PM I'm confused, you did a positive split, yes?

bryancd - 2008-02-03 7:02 PM OK, but your pace still fell off, yes? Just say which camp you are in!

gsmacleod - 2008-02-03 4:31 PM

Here's a decent website that has graphs of anaerobic/aerobic energy system contributions:

http://www.exrx.net/ExInfo/EnergyGraphs.html

You are backwards on assuming that if a pro runs mostly aerobic for a 5k that a novice would run more anaerobic - the reliance on energy systems is almost entirely related to the length of an activity, so a pro would have a higher percentage of anaerobic energy system contribution for a given race distance since they are finished more quickly.

For example, look at the graphs for 10 minutes of activity versus 30.  A pro is going to race a 5k closer to 10 minutes and many novices would be closer to 30 minutes - what you are seeing is the pro would get about 85% of their energy from the aerobic system while the novice closer to 95%.

Shane

Birkierunner - 2008-02-03 7:07 PM

Nope, in my race report I clearly stated my only intent for the race was to hit 6:00 miles.  I think I came pretty damn close to doing that.  When I saw those faster than desired miles at 1 and 3, I consciously said to myself to slow it down and hit those 6's.  It clearly was not a case of going out too fast and doing positive splits (and please don't split hairs over a second or two one way or the other).  Pretty clear what camp I'm in

gsmacleod - 2008-02-02 11:31 PM

Here's a decent website that has graphs of anaerobic/aerobic energy system contributions:

http://www.exrx.net/ExInfo/EnergyGraphs.html

You are backwards on assuming that if a pro runs mostly aerobic for a 5k that a novice would run more anaerobic - the reliance on energy systems is almost entirely related to the length of an activity, so a pro would have a higher percentage of anaerobic energy system contribution for a given race distance since they are finished more quickly.

For example, look at the graphs for 10 minutes of activity versus 30. A pro is going to race a 5k closer to 10 minutes and many novices would be closer to 30 minutes - what you are seeing is the pro would get about 85% of their energy from the aerobic system while the novice closer to 95%.

Shane

Plissken74 - 2008-02-04 12:33 AM Let's take an example so we can discuss better here. Mr.X who runs 800m in 2'06" has an anaerobic capacity of 10 mmol/l: this is quite low since the average is 12,5 (average based on PRO athletes of 800m, based on a statistics of Arcelli E., "Acido lattico e prestazione", 1995) This means that this performance is done in ANAEROBIC way. If Mr.X trains himself for a 5k race, instead of improving the anaerobic threshold, he should improve the anaerobic capacity! If indeed Mr.X has a capcity of 13,2 mmol/l, probably we are dealing with a fast track and field guy with an excellent anaerobic capacity. On the 5k he should improve the anaerobic threshold which is now probably worse than other athletes who can perform like him on the 5k: our Mr.X now run the 5k in an anaerobic way! This example to say that you should consider the anaerobic threshold and capacity of every subject and then you can make that table you reported (for each subject).

amiine - 2008-02-03 9:20 PM 

duuuuuuuuude, I was hoping to bet and win something cool! you are spoiling it

Plissken74 - 2008-02-04 2:33 AM

Let's take an example so we can discuss better here. Mr.X who runs 800m in 2'06" has an anaerobic capacity of 10 mmol/l: this is quite low since the average is 12,5 (average based on PRO athletes of 800m, based on a statistics of Arcelli E., "Acido lattico e prestazione", 1995) This means that this performance is done in ANAEROBIC way. If Mr.X trains himself for a 5k race, instead of improving the anaerobic threshold, he should improve the anaerobic capacity! If indeed Mr.X has a capcity of 13,2 mmol/l, probably we are dealing with a fast track and field guy with an excellent anaerobic capacity. On the 5k he should improve the anaerobic threshold which is now probably worse than other athletes who can perform like him on the 5k: our Mr.X now run the 5k in an anaerobic way! This example to say that you should consider the anaerobic threshold and capacity of every subject and then you can make that table you reported (for each subject).