LM wrote:
Subway Surfers Addiction wrote:
Yet to extrapolate a potential time off one lap is erroneous, it was a very, very good time run by Gebremeskel that day but he never got close to that time again nor has Ndiku ever gotten close to 3:27. Consistency is the only guide we have to make predictions from. The rest is immature speculation.
Yes and no. Let's talk about where all of this is coming from.
The idea behind the concept is that once you know both aerobic threshold and FRC you know exactly how much power an athlete can put down for any given duration (ignoring longer durations where fatigue resistance becomes a factor, or short ones where pure force matters).
With one lap, we can't extrapolate an exact potential, but what we can do is say "the athlete could have run faster than this". How much faster, it's hard to say; but for a 52 it's a minimum of 10s. With more power data as that grows more popular we will be able to hone in on a much more exact figure for this. So with an athlete that runs 13:05 and closes in 52 we know he can run at least 12:55. That's all we can say. Whether he can run 12:05, 12:35, or 12:55 we don't know.
Now if we start to have other fast performances, then we can get an idea. The idea is that if you know two performances, they are going to decay, based on FRC. Take a hypothetical athlete with zero FRC. This doesn't exist but illustrates the concept well. I'll use power because it's easier to conceptualize, and running lap times require exponentially more power.
If this athlete could run 400 in 60s, that would have to come entirely from aerobic energy. Aerobic energy is 100% sustainable, so he could run 800 in 2:00, 5k in 12:30, and 10k in 25:00. This is why you see that athletes that are stronger decay less over time, because aerobic power is a constant supply. You can supply 300w/350w/450w/whatever it may be aerobically for a sustainable period.
FRC on the other hand is a limited reservoir. You have X amount of it, usually measured in kJ. If someone has a 24kJ FRC that means they can do 400w anaerobically for 1'.
Or 800w for 30s.
Or 200w for 2'.
Or 40w for 10'.
Etc.
This is why faster guys decay quickly. A guy with a small FRC, say 12kj, is losing a much smaller amount of power each time the duration increases. Let's take our two examples, big FRC guy and big aerobic engine.
Athlete A: Big aerobic engine might have a threshold of 450w, and an FRC of 6kj
Athlete B: Big FRC monster might have a threshold of 420w, and an FRC of 24kj.
Now how does this breakdown?
Well at all durations (longer than about 1') power is simply aerobic + anaerobic. So at 1':
Athlete A can do 820w (420w aerobic, 400w anaerobic) so that might be like 50s pace
Athlete B can do 550w (450w aerobic, 100w FRC) and gets obliterated running perhaps 54s pace
Now at 5' we can see the gap closing
Athlete A can do 500w (420w aerobic, 80w anaerobic)
Athlete B can do 470w (450w aerobic, 20w anaerobic)
Now out at 30' we have
Athlete A can do 433w (420w aerobic, 13w anaerobic)
Athlete B can do 453w (450w aerobic, 3w anaerobic)
At this point, athlete B, our 10k runner is faster. But of course he can still lose in a slow race. If he run at 420w, that would be at threshold for A, so both A and B would arrive at the the last lap with the full tank of FRC, but now it's A with 24kJ vs B with 6kJ. B gets blown out.
Now of B runs at 430w....then it's different. B is below threshold, and still arrives to finish with 6kj. Meanwhile, A has to run at 430w, 10w of which must come from FRC, so that's going to leave runner A with 6kJ as well, now it's a dead heat who wins. If B runs a bit faster than that, then A will arrive with even less, and likely lose. And of course if B can force A to run faster than 433w, then A will be unable to hang and be dropped.
+1