Do most of the in-swimming-shape and experienced swimmers among you go all out for a whole 50 yards or is there some pacing? In other words are you going top speed the whole time? The reason I'm asking is that right now I can do 25 yards from a standstill in 13 seconds, but my best 50 yard time from a standstill is 33 seconds. (I'm a horrible diver at this point, but once I get my stroke in order I'll start working on that). Anyhow, is it reasonable for me to shoot for a 26 second 50 by just improving my endurance and flip turns, or is it like comparing 50's and 100's where a 50 time will always be less than half a hundred. Thanks for your thoughts.
I don't do a lot of sprinting, but once in a while give it a few shots just to see where I am. Unfortunately I'm unable to do a master's class because I work in shifts and would miss half of them, so I'm pretty much on my own trying to get better. :badday:
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How long can a human perform at 100%?
100% RPE (Rate of perceived effort)? or 100% Peak Velocity? or 100% of peak anaerobic capacity?
Here. I think I have an answer for you.
The rate of ATP recycling by the process of anaerobic glycolysis is about half the rate of the ATP-CP system. (...) Estimates are that a person's power output will decrease by approximately 35% after the first 5 sec of exercise when anaerobic glycolysis becomes the principal source of energy for ATP recycling (Hultman and Sjoholm 1986).
If you fail to deliver max power for reaching peak speed very early in the event, you loose those 5-6 seconds. You just spoiled 'em. Because your ATP-CP system will empty itself anyway, and you won't be able to generate this level of torque later into your race.
Your ability to sustain effort anaerobically is called your anaerobic capacity. It is also often called Lactate Tolerance. Human body, when carefully trained can operate at peak anaerobic capacity power for at least 30-40sec.
For any event lasting around this duration, the goal isn't to try to delay fatigue by pacing yourself, but rather to try to delay fatigue by training to increase your anaerobic capacity, or lactate tolerance, whatever.
Finally (once again) the rate at which the various metabolisms need to operate during a 50m makes it impossible for aerobic metabolism to contribute. Its only contribution in my opinion will be to help reducing the O2 Deficit. And that will occur after the event was swam. That is why some swimmers can book a full 50 LCM no breathing. Aerobic metabolism still contributes, but after the event is finished.
About an event lasting between 20 and 30sec: "Training should focus on improving stroking power and the rate of anaerobic metabolism. Improving buffering capacity or the rate of aerobic metabolism is not important". (E.W. Maglischo, 2003).
I haven't being keeping up on the latest in training theory WRT this issue, but last I heard there was some thought that lactic acid wasn't an inhibiting factor. What is the latest thinking along these lines? By your response I take it that it's back to lactic acid as inhibitor, but perhaps there are some new wrinkles as well.
Thanks,
LBJ I think it is wrong to assume that muscle lactic acid is the cause of muscle fatigue.
First, lactic acid which is produced within the muscle cell rapidly gets converted to lactate when it enters the blood stream. Your body actually loves lactate. It finds a lot of useful things to do with it. One major thing is to turn it back to pyruvate where it could (at threshold speed) be metabolized in presence of O2 by entering inside mitochondria. That process takes place at threshold speed though, certainly not at anaerobic capacity speed.
The problem is that parallel to the increase in blood lactate concentration is the increase of hydrogen ions (H+).
Since you make it explicit in your question that you'd like to know what is the latest thinking... I'd say that the highest profile and most competent physiology experts do insist on the parallel changes that occur along with blood lactate accumulation. That still makes lactate monitoring somehow important. Fatigue do occur whilst lactate level is increasing. Very few actually venture in qualifying the role of blood lactate in regard to muscle fatigue.
The whole issue is still under investigation. New theories are being tested. That probably explains the discrepancy that exists between some of these theories.
How long can a human perform at 100%?
100% RPE (Rate of perceived effort)? or 100% Peak Velocity? or 100% of peak anaerobic capacity?
Here. I think I have an answer for you.
The rate of ATP recycling by the process of anaerobic glycolysis is about half the rate of the ATP-CP system. (...) Estimates are that a person's power output will decrease by approximately 35% after the first 5 sec of exercise when anaerobic glycolysis becomes the principal source of energy for ATP recycling (Hultman and Sjoholm 1986).
If you fail to deliver max power for reaching peak speed very early in the event, you loose those 5-6 seconds. You just spoiled 'em. Because your ATP-CP system will empty itself anyway, and you won't be able to generate this level of torque later into your race.
Your ability to sustain effort anaerobically is called your anaerobic capacity. It is also often called Lactate Tolerance. Human body, when carefully trained can operate at peak anaerobic capacity power for at least 30-40sec.
For any event lasting around this duration, the goal isn't to try to delay fatigue by pacing yourself, but rather to try to delay fatigue by training to increase your anaerobic capacity, or lactate tolerance, whatever.
Finally (once again) the rate at which the various metabolisms need to operate during a 50m makes it impossible for aerobic metabolism to contribute. Its only contribution in my opinion will be to help reducing the O2 Deficit. And that will occur after the event was swam. That is why some swimmers can book a full 50 LCM no breathing. Aerobic metabolism still contributes, but after the event is finished.
About an event lasting between 20 and 30sec: "Training should focus on improving stroking power and the rate of anaerobic metabolism. Improving buffering capacity or the rate of aerobic metabolism is not important". (E.W. Maglischo, 2003).
I haven't being keeping up on the latest in training theory WRT this issue, but last I heard there was some thought that lactic acid wasn't an inhibiting factor. What is the latest thinking along these lines? By your response I take it that it's back to lactic acid as inhibitor, but perhaps there are some new wrinkles as well.
Thanks,
LBJ I think it is wrong to assume that muscle lactic acid is the cause of muscle fatigue.
First, lactic acid which is produced within the muscle cell rapidly gets converted to lactate when it enters the blood stream. Your body actually loves lactate. It finds a lot of useful things to do with it. One major thing is to turn it back to pyruvate where it could (at threshold speed) be metabolized in presence of O2 by entering inside mitochondria. That process takes place at threshold speed though, certainly not at anaerobic capacity speed.
The problem is that parallel to the increase in blood lactate concentration is the increase of hydrogen ions (H+).
Since you make it explicit in your question that you'd like to know what is the latest thinking... I'd say that the highest profile and most competent physiology experts do insist on the parallel changes that occur along with blood lactate accumulation. That still makes lactate monitoring somehow important. Fatigue do occur whilst lactate level is increasing. Very few actually venture in qualifying the role of blood lactate in regard to muscle fatigue.
The whole issue is still under investigation. New theories are being tested. That probably explains the discrepancy that exists between some of these theories.
