Could "Strength" be Defined (Even) More Clearly?

[Dlk93]

So I'm just really way too bored at the moment and want to play devils advocate.

Strength has been defined has the ability to produce force against an external resistance. Thus, someone's strength has improved if and only if one is able to produce more force against an external resistance than one produced last time.

Defined this way, doesn't increasing the amount of reps one can do at a given weight classify as getting stronger? Being able to rep out 225 for 8 vs 225 for 12 for example. We classify the latter as increasing muscular endurance but not as getting stronger. But collectively, tonnage-wise, isn't one producing more force overall in the case of lifting 225 for 12, and therefore stronger?

[Tom Campitelli]

Thus, someone's strength has improved if and only if one is able to produce more force against an external resistance than one produced last time.

If the definition is complete, then, yes.

Defined this way, doesn't increasing the amount of reps one can do at a given weight classify as getting stronger? Being able to rep out 225 for 8 vs 225 for 12 for example. We classify the latter as increasing muscular endurance but not as getting stronger. But collectively, tonnage-wise, isn't one producing more force overall in the case of lifting 225 for 12, and therefore stronger?

This is an interesting question. In your example, someone who could bench press 225 for 12 reps would very likely have a higher 1 RM than someone who could only bench press 8. Things do get a little fuzzier when you get into higher rep ranges, however. For example, does the person that can bench 225 for 14 have a higher 1 RM bench than someone that does it for 12? Maybe. That probably could not be answered without conducting the experiment.

Further, the idea that strength can only be defined as the generation of force against an external resistance is one that is open to challenge. When we discuss this at the seminars, the example we give is the force the spinal erectors generate between each of the vertebrae. When you hold your back in extension on a deadlift, that requires force production at those sites and therefore strength. There is no good way to measure the magnitude of that force production so the "external resistance" portion enters into the definition for the purposes of making it much easier to quantify these things. Also, as CJ Gotcher and I have discussed before, when you do a pullup, where is the resistance? Is it external? If so, external to what? If not external, does it require strength to do a pullup?

Bodyweight exercises make thinking about this complicated. They require strength to perform, but quantifying that strength and comparing that strength between individuals gets difficult quickly.

[Dlk93]

Right. I was assuming that the person repping 12 and the person repping 8 had the same 1RM, perhaps because the former delves into higher reps more frequently than the latter. The 12-er isn't "stronger" in terms of his 1RM, but in terms of ability to produce tonnage. (But I'm obviously granting that it's way more likely in the real world that the 12-er has a higher 1RM than the 8-er. I have a philosophy degree so I tend to spend too much time in theoretical/thought-experiment-mode, so that's where the question is coming from.)

And sure, I guess the word "external" sort of complicates things, and might be better left out so as to leave the word ("strength") more generalizable, e.g. to bodyweight exercises. If we did that, it would just be "the ability to produce force against a resistance" and in the case of bw exercises the resistance would be the weight of one's own body.

Or could we think of gravity as the force of resistance that's external to..ourselves..?

[Tom Campitelli]

Gravity is, of course, the force against which we produce force. However, you said the following:

Thus, someone's strength has improved if and only if one is able to produce more force against an external resistance than one produced last time.

Can we be that absolute? "If and only if" is a fairly limiting phrase.

[Marenghi]

Adding to that, you can have a basic definition of strength - and the above is more or less what is used in the literature.

And then enter the many subsets of "strength" you can define, measure and get better at - or just fool around comparing yourself to others (that is if theyre willing to compete against you in "concentric-only half-ROM v>4m/s front squatting strength").

Because Strength is specific: Why are strength gains specific? | S&C Research

[John Hanley]

I have a philosophy degree so I tend to spend too much time in theoretical/thought-experiment-mode

You're certainly not the first person to fuss over 1) peak-force production in a given motor program [non recruitment rate limited], 2) peak force in a ballistic version of the motor program [recruitment rate limited], 3) work capacity of the PCr energy system of the motor program, 4) PCr + glycolytic work capacity of the motor program [anaerobic work capacity], 5) aerobic work capacity of the motor program.

When we talk about "strength" around here, we're talking about 1. What are you daydreaming about? 3 and 4? Why do you want to call these things "strength"?

[Tom Campitelli]

Because Strength is specific: Why are strength gains specific? | S&C Research

In fact, we make the opposite argument. Strength is the most general of adaptations.

[Dlk93]

I guess my quarrel enters when I wonder what "more force" means. "More" in terms of what? It's easy enough to say you've gotten stronger when your 1RM goes up..but like I've mentioned, what about when someone's ability to produce tonnage goes up but not one's 1RM?

If you can do 100 pull ups in a 10 minute bout, we say that being able to do 101 isn't going to help you get much better at anything. And I agree. But we also say (or at least I was under this impression) that you haven't gotten any stronger. But if you're now able to produce more tonnage overall, and by definition produce more force overall, then how have you not gotten stronger?

I think Hanley is addressing my problem though what he's saying is a bit over my head at this point. Hanley, do 3 and 4 entail the ability to produce more tonnage if improved? I think I understand how they differ from 1 and how 1 is generally what we're talking about when talking about strength. But my question is, if one becomes more able to produce tonnage, while not necessarily increase one's 1RM, then how has one not gotten stronger by the current definition of "strength" that we're working with? Sure, if we used 1 as the definition of strength that problem would go away I suppose. But it's certainly a lot less user friendly than "the ability to produce force."

[Tom Campitelli]

I guess my quarrel enters when I wonder what "more force" means. "More" in terms of what? It's easy enough to say you've gotten stronger when your 1RM goes up..but like I've mentioned, what about when someone's ability to produce tonnage goes up but not one's 1RM?

You need to be more precise with your language. "More force" is very easily measured, especially when it comes to barbells. One does not "produce tonnage," either. Tonnage is a very rough calculation that can tell you something about a trainee's overall volume. Tonnage is probably most useful when looked at over longer periods, such as a week. Force and tonnage are not equivalent. One can be directly measured. The other is a semi-quantitative concept that may or may not be useful when making program decisions. The quantities in which you are more likely interested are: work, power, and energy. I will leave it to you to frame your questions around those concepts so we can further this discussion.

If you can do 100 pull ups in a 10 minute bout, we say that being able to do 101 isn't going to help you get much better at anything.

It will make you better at doing more pullups in 10 minutes.

But we also say (or at least I was under this impression) that you haven't gotten any stronger.

I don't know that we do say that, although it is probably impossible to realistically measure a strength increase in the scenario that you laid out. Any increase in force production would be overwhelmed by other variables.

But if you're now able to produce more tonnage overall, and by definition produce more force overall, then how have you not gotten stronger?

Once again, your use of terminology here doesn't really make sense. Force, work, power, energy, strength, and endurance are all words that have specific meanings and you need to be clearer about what you are asking. Power, whether in the Olympic lifts or on a bicycle, can be directly measured. Power and energy are very closely related and so is work for that matter. CrossFit talks about "work capacity," which is a fairly useful construction. Whatever the case, you don't produce more tonnage. You do more work in a given amount of time, which is probably correctly described as energy (units of Joules or Watt-seconds), but I reserve the right to change my mind on that.

All of this is overlain on the vagaries of bioenergetics. How muscles produce force once vs. over a prolonged period is fairly complicated. Books are written about it. Doing more work in a given period of time is related to, but not solely dependent upon, peak muscular force production. There are people who, for multiple reasons, will be able to repetitively produce levels of force over a given amount of time in ways that enable them to outwork other, stronger individuals. Those people can be said to have a greater work capacity. However, you can imagine exercises and scenarios in which one person could outwork another, yet not have as high of a 1 RM as their counterpart.

[Alexander Rix]

Tonnage has units of pounds, as does force. Usually when we see things with the same unit, we think they can be compared directly. But, I think its clear that Tonnage and Force cannot be directly compared, as lifting 100x5x20 and 1000x1x1 have the same tonnage but very different forces are involved in each lift. This implies that Tonnage is something quite different than Force.

Recall that one needs sufficient volume at sufficient intensity to trigger SRA.

We usually think of the number of reps in set as a proxy for intensity. A 3RM is 90% intensity and so on (of course, this varies from individual to individual, but that is besides the point). That implies that 100x5x20 and 1000x1x1 are very different intensities as well.

The reason why we can predict a 1 RM based off a 3 RM or 5RM is because we have enough training data to make reasonably accurate predictions of the 1RM

270x5x3
300x5
340x1

all have the same units and all mean very different things, and the last one is what we define to be strength.