The Kim Caldwell System

The first point in the summary of CKC's system that started this post was:

1. Effort. All out, last two minutes of the championship game effort every time you're on the court. Kim has said it's an effort-based system. She's said when done right, players are glad to come out. I see it like interval training -- going really hard for 90 seconds to 3 minutes, then resting, then doing it again. Defense and rebounding are a lot about effort, and we all know what Pat said about offense, defense, and rebounding.

The "interval training" comparison was just an idea. I wondered if there was a basis for Kim's substitution pattern in physiological science. So, I asked ChatGPT for a report. I didn't run this one through multiple, but feel free to double check me. Anyway, here is what I got:

Yes — there is physiology that makes your “interval training” intuition plausible. But there isn’t a magic cliff at 2:00 where biology flips from “fine” to “wrecked.” What is real is a fatigue curve: as an all-out shift gets longer, the stuff that lets you repeat high-power actions (accelerate, stop, jump, press, close out) degrades fast, and the recovery you’d need starts to exceed what basketball naturally gives you unless you sub.

The key mechanism: refueling the “burst” battery (PCr)​

Most of the explosive actions in basketball are powered by the ATP–phosphocreatine system (PCr) plus anaerobic glycolysis. PCr is basically the immediate “battery” that helps you hit repeated bursts.

  • PCr recovery after intense work is fast at first (time constants on the order of ~18–30 seconds in healthy people/athletes in many conditions), as long as muscle pH hasn’t dropped too much; acidosis slows recovery. (ScienceDirect)
  • In repeated-sprint research, performance recovery tracks PCr recovery: after a brutal sprint bout, PCr resynthesis correlated with how much work athletes could produce when they went again. (PLOS)
Translation to a press-heavy system: you sub so the player’s PCr can come back up enough to have “pop” again, instead of staying out there while that battery is drained and their bursts turn into jogs, late closeouts, and fouls.

Why “going longer” becomes self-defeating​

As you keep the intensity high without a real break, you lean harder on anaerobic glycolysis and accumulate byproducts (including H+), and neuromuscular output drops. Recovery then takes longer.

A nice way to see the idea: in an intermittent sprint study (team-sport relevant), shorter recoveries (60s) led to lower mean power than 90–120s, and the authors point out these rest intervals sit between a fast and slow phase of PCr resynthesis (~20s and ~180s) — meaning you’re getting partial, not complete, recovery. (ScienceDirect)

That maps cleanly onto hockey-style subs: sit 1–3 minutes, come back with restored power.

Why basketball specifically rewards short, hard “shifts”​

Basketball isn’t a steady run; it’s repeated bursts. Even in normal styles, play is starts/stops and short segments. One sports-science summary notes average play segments around 12–20 seconds, with heavy reliance on anaerobic metabolism layered on top of aerobic support. (Gatorade Sports Science Institute)

And match data show the game is physiologically taxing: elite players can sit at very high heart rates and show meaningful lactate levels (a marker that anaerobic glycolysis is heavily involved). (PMC)

Caldwell’s system pushes the game more toward continuous demand (more pressure, more running, more repeated accelerations). That tends to make fatigue show up sooner unless minutes are managed.

So does “under 2 minutes” have scientific meaning?​

Not as a hard threshold. But it’s a reasonable coaching heuristic because:

  • A 90–120s shift at max press intensity is long enough to get you deep into the fatigue curve (PCr down, glycolysis up, decision-making and footwork deteriorate).
  • Off-court time of 1–3 minutes gives you meaningful partial PCr recovery (fast early recovery), which is exactly what you need for repeated high-intensity bursts. (ScienceDirect)
 
The first point in the summary of CKC's system that started this post was:

1. Effort. All out, last two minutes of the championship game effort every time you're on the court. Kim has said it's an effort-based system. She's said when done right, players are glad to come out. I see it like interval training -- going really hard for 90 seconds to 3 minutes, then resting, then doing it again. Defense and rebounding are a lot about effort, and we all know what Pat said about offense, defense, and rebounding.

The "interval training" comparison was just an idea. I wondered if there was a basis for Kim's substitution pattern in physiological science. So, I asked ChatGPT for a report. I didn't run this one through multiple, but feel free to double check me. Anyway, here is what I got:

Yes — there is physiology that makes your “interval training” intuition plausible. But there isn’t a magic cliff at 2:00 where biology flips from “fine” to “wrecked.” What is real is a fatigue curve: as an all-out shift gets longer, the stuff that lets you repeat high-power actions (accelerate, stop, jump, press, close out) degrades fast, and the recovery you’d need starts to exceed what basketball naturally gives you unless you sub.

The key mechanism: refueling the “burst” battery (PCr)​

Most of the explosive actions in basketball are powered by the ATP–phosphocreatine system (PCr) plus anaerobic glycolysis. PCr is basically the immediate “battery” that helps you hit repeated bursts.

  • PCr recovery after intense work is fast at first (time constants on the order of ~18–30 seconds in healthy people/athletes in many conditions), as long as muscle pH hasn’t dropped too much; acidosis slows recovery. (ScienceDirect)
  • In repeated-sprint research, performance recovery tracks PCr recovery: after a brutal sprint bout, PCr resynthesis correlated with how much work athletes could produce when they went again. (PLOS)
Translation to a press-heavy system: you sub so the player’s PCr can come back up enough to have “pop” again, instead of staying out there while that battery is drained and their bursts turn into jogs, late closeouts, and fouls.

Why “going longer” becomes self-defeating​

As you keep the intensity high without a real break, you lean harder on anaerobic glycolysis and accumulate byproducts (including H+), and neuromuscular output drops. Recovery then takes longer.

A nice way to see the idea: in an intermittent sprint study (team-sport relevant), shorter recoveries (60s) led to lower mean power than 90–120s, and the authors point out these rest intervals sit between a fast and slow phase of PCr resynthesis (~20s and ~180s) — meaning you’re getting partial, not complete, recovery. (ScienceDirect)

That maps cleanly onto hockey-style subs: sit 1–3 minutes, come back with restored power.

Why basketball specifically rewards short, hard “shifts”​

Basketball isn’t a steady run; it’s repeated bursts. Even in normal styles, play is starts/stops and short segments. One sports-science summary notes average play segments around 12–20 seconds, with heavy reliance on anaerobic metabolism layered on top of aerobic support. (Gatorade Sports Science Institute)

And match data show the game is physiologically taxing: elite players can sit at very high heart rates and show meaningful lactate levels (a marker that anaerobic glycolysis is heavily involved). (PMC)

Caldwell’s system pushes the game more toward continuous demand (more pressure, more running, more repeated accelerations). That tends to make fatigue show up sooner unless minutes are managed.

So does “under 2 minutes” have scientific meaning?​

Not as a hard threshold. But it’s a reasonable coaching heuristic because:

  • A 90–120s shift at max press intensity is long enough to get you deep into the fatigue curve (PCr down, glycolysis up, decision-making and footwork deteriorate).
  • Off-court time of 1–3 minutes gives you meaningful partial PCr recovery (fast early recovery), which is exactly what you need for repeated high-intensity bursts. (ScienceDirect)
Good info, thanks. I'm sure there are studies out there that take the opposite position. Also, all the physics disregard what gets sacrificed mentally for the line subbing system. The physical rest very well may be sufficient, but does that compensate for the lack of rhythm and flow that the players are allowed? We'll see how that plays out this year, but lack of game flow seems to be hurting the team so far this year, especially offensively.
 
The physical rest very well may be sufficient, but does that compensate for the lack of rhythm and flow that the players are allowed?

That is my entire beef with the system. Like I've mentioned a few times before, in my personal experience it always took me at least 4 or 5 minutes just to catch my breath at the beginnings of games and second halves. Getting into an extended rhythm was EVERYTHING to me as a player, so it makes me feel "off" even watching this team play from the stands or on tv.

I know that sounds crazy, and that most people are not like I was. But I am 100% certain that the majority of athletes benefit greatly from getting into the rhythm of the game by remaining in the game for a good while, and if they start "feeling it," then the last thing you want to do is take them out of the game. You want them to start showing that they NEED -- if they ever do -- to come out for a rest, NOT pull them so that the hot hand cools down.

Other than that, I'm good with it. lol
 
Good info, thanks. I'm sure there are studies out there that take the opposite position. Also, all the physics disregard what gets sacrificed mentally for the line subbing system. The physical rest very well may be sufficient, but does that compensate for the lack of rhythm and flow that the players are allowed? We'll see how that plays out this year, but lack of game flow seems to be hurting the team so far this year, especially offensively.
Who remembers game 1 of the season and Jaida was well on her way to a 20 point debut and Kim kept taking her out at critical moments of the game and wouldn't allow her to "cook" to close the game out.

There have also been other moments Kim will pick odd moments trading her defense for offense (and vice versa) after momentum shift or a potential run has happened. It grinds my gears because usually who she brings in for her subbing makes absolutely no sense at that given time or game. No lie, sometimes the system reminds of the spoiled child who has a bunch of toys and has to play with all of them multiple times or they are bored but still goes a repetitive cycle.
 
That is my entire beef with the system. Like I've mentioned a few times before, in my personal experience it always took me at least 4 or 5 minutes just to catch my breath at the beginnings of games and second halves. Getting into an extended rhythm was EVERYTHING to me as a player, so it makes me feel "off" even watching this team play from the stands or on tv.

I know that sounds crazy, and that most people are not like I was. But I am 100% certain that the majority of athletes benefit greatly from getting into the rhythm of the game by remaining in the game for a good while, and if they start "feeling it," then the last thing you want to do is take them out of the game. You want them to start showing that they NEED -- if they ever do -- to come out for a rest, NOT pull them so that the hot hand cools down.

Other than that, I'm good with it. lol
Regarding needing rhythm get in a grove, pretty sure the macho “just work harder” ethos of this system would say the players just have to get over that. Part of the Great Unlearning.
 
I think my main beef with the system is it does not allow the top players to play enough minutes or the coaches don't care if they do. I think the team has to be better with Barker, Pauldo, Cooper, Latham, Spearman, and maybe Civil and Robertson playing about 170 minutes of the 200 minutes and everyone else filling in the thirty. Who you rather have 20 minutes of Barker and 20 minutes of someone else or 32 Barker and 8 someone else and the same for the other top players.

The system seems to prevent this from a physical situation where just to many minutes to play and stay productive. So were thinking that playing 11 equal were going to tire out the other teams top players and created a shot deficit that what we do on offense that is below average doesn't matter cause were going to shoot it so much more that we will still win.

This is where the system has been awesome against any team ranked over 100 and has failed against the very top teams. Were not tiring anybody out and this year not creating any shot deficits of anyone ranked. Our top players are losing minutes based on what other teams top players are playing. They keep producing cause of more minutes on floor while ours do more sitting on the bench. I can't see it ever working against top teams unless you can somehow perfect a defense and rebounding team that holds the other teams scoring down. They just have an unusually bad shooting night. That is what shot deficit is supposed to do win turnovers and rebounds against top talented teams hasn't been close to enough of a deficit to make shooting 40 percent a winning strategy. The 40 percent is probably happening because our top three four players are playing 23 minutes on average.

The only way I see to have a better chance of winning is for the top players to play more and this system is not designed to let that happen.
 
Am I wrong that the limited and non-consecutive minutes also hold down player stats? What do we think Coop and Barker would be averaging in a “normal “ system? Esp one designed to get them the ball in their spots.
I think they’d both be averaging around 20 ppg and a double double with rebounds. And I think Mia would eventually average a double double with assists.
 
The first point in the summary of CKC's system that started this post was:

1. Effort. All out, last two minutes of the championship game effort every time you're on the court. Kim has said it's an effort-based system. She's said when done right, players are glad to come out. I see it like interval training -- going really hard for 90 seconds to 3 minutes, then resting, then doing it again. Defense and rebounding are a lot about effort, and we all know what Pat said about offense, defense, and rebounding.

The "interval training" comparison was just an idea. I wondered if there was a basis for Kim's substitution pattern in physiological science. So, I asked ChatGPT for a report. I didn't run this one through multiple, but feel free to double check me. Anyway, here is what I got:

Yes — there is physiology that makes your “interval training” intuition plausible. But there isn’t a magic cliff at 2:00 where biology flips from “fine” to “wrecked.” What is real is a fatigue curve: as an all-out shift gets longer, the stuff that lets you repeat high-power actions (accelerate, stop, jump, press, close out) degrades fast, and the recovery you’d need starts to exceed what basketball naturally gives you unless you sub.

The key mechanism: refueling the “burst” battery (PCr)​

Most of the explosive actions in basketball are powered by the ATP–phosphocreatine system (PCr) plus anaerobic glycolysis. PCr is basically the immediate “battery” that helps you hit repeated bursts.

  • PCr recovery after intense work is fast at first (time constants on the order of ~18–30 seconds in healthy people/athletes in many conditions), as long as muscle pH hasn’t dropped too much; acidosis slows recovery. (ScienceDirect)
  • In repeated-sprint research, performance recovery tracks PCr recovery: after a brutal sprint bout, PCr resynthesis correlated with how much work athletes could produce when they went again. (PLOS)
Translation to a press-heavy system: you sub so the player’s PCr can come back up enough to have “pop” again, instead of staying out there while that battery is drained and their bursts turn into jogs, late closeouts, and fouls.

Why “going longer” becomes self-defeating​

As you keep the intensity high without a real break, you lean harder on anaerobic glycolysis and accumulate byproducts (including H+), and neuromuscular output drops. Recovery then takes longer.

A nice way to see the idea: in an intermittent sprint study (team-sport relevant), shorter recoveries (60s) led to lower mean power than 90–120s, and the authors point out these rest intervals sit between a fast and slow phase of PCr resynthesis (~20s and ~180s) — meaning you’re getting partial, not complete, recovery. (ScienceDirect)

That maps cleanly onto hockey-style subs: sit 1–3 minutes, come back with restored power.

Why basketball specifically rewards short, hard “shifts”​

Basketball isn’t a steady run; it’s repeated bursts. Even in normal styles, play is starts/stops and short segments. One sports-science summary notes average play segments around 12–20 seconds, with heavy reliance on anaerobic metabolism layered on top of aerobic support. (Gatorade Sports Science Institute)

And match data show the game is physiologically taxing: elite players can sit at very high heart rates and show meaningful lactate levels (a marker that anaerobic glycolysis is heavily involved). (PMC)

Caldwell’s system pushes the game more toward continuous demand (more pressure, more running, more repeated accelerations). That tends to make fatigue show up sooner unless minutes are managed.

So does “under 2 minutes” have scientific meaning?​

Not as a hard threshold. But it’s a reasonable coaching heuristic because:

  • A 90–120s shift at max press intensity is long enough to get you deep into the fatigue curve (PCr down, glycolysis up, decision-making and footwork deteriorate).
  • Off-court time of 1–3 minutes gives you meaningful partial PCr recovery (fast early recovery), which is exactly what you need for repeated high-intensity bursts. (ScienceDirect)
Dammit Retro! Ya got me playing Devil’s Advocate here… second wind:

IMG_7409.jpeg
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Good info, thanks. I'm sure there are studies out there that take the opposite position. Also, all the physics disregard what gets sacrificed mentally for the line subbing system. The physical rest very well may be sufficient, but does that compensate for the lack of rhythm and flow that the players are allowed? We'll see how that plays out this year, but lack of game flow seems to be hurting the team so far this year, especially offensively.
The physiological mechanisms of the ATP-PC system are well documented in terms of their function and depletion and replenishment times. There aren't other studies taking opposite positions. This system is kind of like gravity.

I think the counter to the 90-120 second subbing pattern comes from systems theory which holds that subsystem optimization leads to a reduction in whole system functionality (aka the optimization paradox).

So, CKC's system optimizes each player's explosive potential but, perhaps, at the expense of team continuity and rhythm.

We are also talking about marginal differences. Since basketball games are not continuous action but have many breaks for foul calls, FTs, etc., players are getting partial ATP_PC recovery in these short breaks and are probably working at 80 to 85% of their max even with extended playing time. So, the real question is does the 15 to 20% in explosiveness gained through optimization (via rapid subbing) outweigh the previously noted costs? Also, for trained athletes, ATP_PC levels completely recover after about 3 minutes. So, for example, TOs and breaks between quarters provide the needed replentishment time.

Also, basketball, unlike sprinting or power lifting is not all about the ATP-PC system. Most estimates have it accounting for about 60% of basketball plays (jumping for a rebound, quick acceleration), with 20 percent reliant on the glycolytic system, which is used for more extended forms of exertion, like running the court on a fast break or fighting through multiple screens and the aerobic system is also involved as higher aerobic fitness improves the recovery time of the other systems. Getting the conditioning mix right between the anaerobic and aerobic systems is one of the more challenging tasks for athletic trainers in sports like basketball, hockey and soccer which blend anaerobic explosiveness with aerobic endurance.
 
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The physiological mechanisms of the ATP-PC system are well documented in terms of their function and depletion and replenishment times. There aren't other studies taking opposite positions. This system is kind of like gravity.

I think the counter to the 90-120 second subbing pattern comes from systems theory which holds that subsystem optimization leads to a reduction in whole system functionality (aka the optimization paradox).

So, CKC's system optimizes each player's explosive potential but, perhaps, at the expense of team continuity and rhythm.

We are also talking about marginal differences. Since basketball games are not continuous action but have many breaks for foul calls, FTs, etc., players are getting partial ATP_PC recovery in these short breaks and are probably working at 80 to 85% of their max even with extended playing time. So, the real question is does the 15 to 20% in explosiveness gained through optimization (via rapid subbing) outweigh the previously noted costs? Also, for trained athletes, ATP_PC levels completely recover after about 3 minutes. So, for example, TOs and breaks between quarters provide the needed replentishment time.

Also, basketball, unlike sprinting or power lifting is not all about the ATP-PC system. Most estimates have it accounting for about 60% of basketball plays (jumping for rebound, quick acceleration), with 20 percent reliant on the glycolytic system, which is used for more extended forms of exertion, like running the court on a fast break or fighting through multiple screens and the aerobic system is involved as higher aerobic fitness improves the recovery time of the other systems. Getting the conditioning mix right between anaerobic and aerobic is one of the more challenging tasks for athletic trainings in sports like basketball, hockey and soccer which blend anaerobic explosiveness with aerobic endurance.
…hmm. 🤔

Note to self: choose wisely to engage @madtown in an argument.
 
I understand all of the numbers crunching and strategy/style deep analysis. One final thought here is that all of the analysis is fine, but the actual game scores will tell us what is real. Fingers crossed for the LV’s. Might be as simple as letting their best 5 be on the court for extended minutes imho.
 
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Who remembers game 1 of the season and Jaida was well on her way to a 20 point debut and Kim kept taking her out at critical moments of the game and wouldn't allow her to "cook" to close the game out.

There have also been other moments Kim will pick odd moments trading her defense for offense (and vice versa) after momentum shift or a potential run has happened. It grinds my gears because usually who she brings in for her subbing makes absolutely no sense at that given time or game. No lie, sometimes the system reminds of the spoiled child who has a bunch of toys and has to play with all of them multiple times or they are bored but still goes a repetitive cycle.

This I think the subbing is just a like a "timer" with no thought on what makes sense for the game being played on the floor (i.e No in-game coaching whatsoever). The subbing plan is probably pre-set, and they just let it happen.
 
I understand all of the numbers crunching and strategy/style deep analysis. One final thought here is that all of the analysis is fine, but the actual game scores will tell us what is real. Fingers crossed for the LV’s. Might be as simple as letting their best 5 be on the court for extended minutes imho.
Yeah after reading all the different super Lady VOLS analysis I've deciphered the answer. 🤔 Really believe playing better defense and rebounding can and will stop the blowouts. Now to have a better shot and winning the most games top 4 players need around 34 minutes next 4 around 6 minutes per game. This should be used against all ranked teams. We don't need to have large deficits to try and overcome , this will just cause more long term fatigue. GLV 💥
 
Yeah after reading all the different super Lady VOLS analysis I've deciphered the answer. 🤔 Really believe playing better defense and rebounding can and will stop the blowouts. Now to have a better shot and winning the most games top 4 players need around 34 minutes next 4 around 6 minutes per game. This should be used against all ranked teams. We don't need to have large deficits to try and overcome , this will just cause more long term fatigue. GLV 💥
Efficiency on offense doesn't seem to be something this team is capable of when they play a decent team and you really have to create a rather large shot deficit to overcome a 10 percent less Field goal percentage. So yes seems like the best option for some success is defense and rebounding keeping the other team to a lower point total. I think right now that looks like the best way to wins some games. Don't know if were capable of doing it. but rebounding and defense are certainly more effort based than shooting and offense so it looks like that is where the system should try to get better.
 
I understand all of the numbers crunching and strategy/style deep analysis. One final thought here is that all of the analysis is fine, but the actual game scores will tell us what is real. Fingers crossed for the LV’s. Might be as simple as letting their best 5 be on the court for extended minutes imho.
Simple doesn't seem to exist in this system. Everything is overthought and overwrought. Probably why its so hard to learn.
Efficiency on offense doesn't seem to be something this team is capable of when they play a decent team and you really have to create a rather large shot deficit to overcome a 10 percent less Field goal percentage. So yes seems like the best option for some success is defense and rebounding keeping the other team to a lower point total. I think right now that looks like the best way to wins some games. Don't know if were capable of doing it. but rebounding and defense are certainly more effort based than shooting and offense so it looks like that is where the system should try to get better.
I have a feeling having an organized offense that doesn't involve a quick 3 or a layup off a turnover is an inconvenience to CKC. To them having to run O in the half court is punishment for not giving enough "effort" to make Plan A work.

So yeah, improvement depends mostly on defense and rebounding.
 
Simple doesn't seem to exist in this system. Everything is overthought and overwrought. Probably why its so hard to learn.

I have a feeling having an organized offense that doesn't involve a quick 3 or a layup off a turnover is an inconvenience to CKC. To them having to run O in the half court is punishment for not giving enough "effort" to make Plan A work.

So yeah, improvement depends mostly on defense and rebounding.
You really, really don't think much of Kim Caldwell as a coach, do you? Not only does she not understand basketball, she lacks the personal characteristics necessary to improve.

I am amazed at your ability to intuit all of this just from observing games and interviews.
 
You really, really don't think much of Kim Caldwell as a coach, do you? Not only does she not understand basketball, she lacks the personal characteristics necessary to improve.

I am amazed at your ability to intuit all of this just from observing games and interviews.
Yep. Pitchforks have been sharpened and the torches are oiled. I’ve seen this movie before… 🍿
 
You really, really don't think much of Kim Caldwell as a coach, do you? Not only does she not understand basketball, she lacks the personal characteristics necessary to improve.

I am amazed at your ability to intuit all of this just from observing games and interviews.
Not sure what you’re talking about. Once again, none of this is ever personal.I don’t think much of her system at all but she seems a fine, upstanding citizen. Why mix this up?

My opinion that half court offense is a low priority is really easy to intuit from observing games and interviews. Defensive pressure and pace is far more important.Not amazing at all and in no way a character assessment. Im surprised you’re surprised.
 
Describing an organized offense as an inconvenience is attribution of attitude or character. There are other examples in your posts of similar statements. You go beyond comments about observable phenomena to your beliefs about interior mental states of Coach Caldwell and her staff. Such musings are subject to "attributional bias," and they make it difficult to discuss your points, especially for those of us who are inclined to see Coach Caldwell in a more favorable light. Such comments being up values, not behavior.

That's unfortunate, because you make some very good points. They just get mixed in with things you have no way of knowing such as what Kim Caldwell thinks, feels, and believes.
 
Describing an organized offense as an inconvenience is attribution of attitude or character. There are other examples in your posts of similar statements. You go beyond comments about observable phenomena to your beliefs about interior mental states of Coach Caldwell and her staff. Such musings are subject to "attributional bias," and they make it difficult to discuss your points, especially for those of us who are inclined to see Coach Caldwell in a more favorable light. Such comments being up values, not behavior.

That's unfortunate, because you make some very good points. They just get mixed in with things you have no way of knowing such as what Kim Caldwell thinks, feels, and believes.
This is a cuckoo attribution of my attitude and character. But let’s take this out of the realm of the personal, where it has no place. My observation is that in this system, having to slow down and run half court offense is an inconvenience thats necessitated by failure of plan A to work. Therefore a low priority.

Thats a strategic basketball choice and in no way a test of character. For the record, I think pre 2000 Pat Summitt felt the same way.
 
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