A Different Weight-ST Relationship

[Anthony]

Originally Posted by Varyon

As for the wrestling match, if the dog opts to get its mouth involved, aren't things typically in the dog's favor?

Well, the bite does damage, which helps. If the dog it biting on something durable enough to not take damage (various types of armor, mostly), it's gonna lose.

I mean, you can say "the dog has ST 11 but big penalties on anything that actually uses ST", but that seems perversely complex. Also, realistically what matters for a lot of purposes (including weapon damage and wrestling) is actually torque, which is very simple: it's linear in mass.

[Flyndaran]

Originally Posted by Varyon

I was unaware of this, but it makes a lot of sense. Any idea on what the effect would be? Getting away from primates, GURPS default would have a typical ~77 lb German Shepherd be around ST 8.5. My proposal would have such a dog - who would presumably be around 0.82 yards long (Wikipedia notes an average of 25 inches tall, and a ratio of 10 to 8.5 for length to height) - instead have ST around 10.8 (round it up to 11). A typical German Shepherd being a bit stronger than a typical human seems more appropriate than the other way around, but does ST 11 sound about right, or would their higher proportion of fast twitch fibers make them stronger?

Or does a German Shepherd actually have a more human-like proportion of slow-vs-fast-twitch fibers, seeing as wolves and dogs are also endurance runners?

It was hard enough finding actual studies on human vs. chimp fiber ratios. I'm not sure if it's ever been properly done on dogs, especially with how hard breeding can alter nearly any feature.
Chimp muscles, pound per pound, are only 50% stronger than human. The rest of why they're twice as strong as comparably sized humans is likely a collection of other things such as articulation based leverage. Chimps still have not insignificant amounts of slow twitch fibers though.
IIRC, the study suggested around a 60%/40% slow/fast for us and a 40%/60% for them.

[Varyon]

Originally Posted by Anthony

Well, the bite does damage, which helps. If the dog it biting on something durable enough to not take damage (various types of armor, mostly), it's gonna lose.

That makes sense, I was probably thinking about things improperly. Guess that kind of kills my concept in the water.

Originally Posted by Anthony

Also, realistically what matters for a lot of purposes (including weapon damage and wrestling) is actually torque, which is very simple: it's linear in mass.

Doesn't that sort of fly in the face of the square-cube law? Or does that law only really apply to how much weight a creature can carry around?

Originally Posted by Flyndaran

It was hard enough finding actual studies on human vs. chimp fiber ratios. I'm not sure if it's ever been properly done on dogs, especially with how hard breeding can alter nearly any feature.

I did find one study that gave a bit of a teaser - it noted that type 2A fibers are the predominant type of fast-twitch fibers in dogs, and that they make up 30-50% of all skeletal muscle overall in dogs (I assume the range is thanks to differences in breeds).

Originally Posted by Flyndaran

Chimp muscles, pound per pound, are only 50% stronger than human. The rest of why they're twice as strong as comparably sized humans is likely a collection of other things such as articulation based leverage. Chimps still have not insignificant amounts of slow twitch fibers though.
IIRC, the study suggested around a 60%/40% slow/fast for us and a 40%/60% for them.

Interesting. That implies muscle strength is basically determined by fast-twitch fibers, but that effective strength has a lot of impact from leverage that my system fails to account for, and this is possibly a bit part of why mine has dogs being too strong. In fact, it seems arm length may play a rather significant role it determining arm strength, such that mecha (or aliens, or whatever) with SM+4 weight but SM+3 length arms may well have weaker arms than those with SM+4 weight and SM+4 length. Which... is pretty much the opposite of what I expected, and of the purpose of this thread. Huh.

[Anthony]

Originally Posted by Varyon

Doesn't that sort of fly in the face of the square-cube law? Or does that law only really apply to how much weight a creature can carry around?

The conversion between torque and force is that torque is equal to force * distance from center of rotation. This gives rise to the square-cube law -- torque is cubic in linear dimension, distance is linear, so net available force is quadratic in linear dimension.

However, the amount of energy that can be generated by a strike is proportional to force * limb length, or linear in torque. Likewise, in a wrestling situation, someone who can apply 20 lb of force at a distance of 3' from the torso is actually much stronger than someone who can apply 20 lb of force at a distance of 2' -- because if he bends his arms so he's only applying the force at a distance of 2', he's now applying 30 lb force. This has an upper limit, but outside of extreme differences in size (say, 4+ levels of SM) figuring wrestling ability is linear in torque is probably fair.

[VonKatzen]

My solution was to just force a ratio of ST and Lifting ST (the latter always being higher) for realistic games, and as far as animals go I'd build it custom or ignore it. This is also for other reasons: to make very strong lifters in GURPS you end up making them do absurd amounts of damage that are totally unrealistic and over-the-top. Lifting ST should always be higher than ST in humans, Striking ST should almost never be higher than ST in humans, and Low ST Humans should almost always have higher HP than ST.

In many ways the rules/optional rules in GURPS are more realistic than the core attributes (Aristotle did not have an 18 IQ!)

[Tomsdad]

Originally Posted by Anthony

Well, the bite does damage, which helps. If the dog it biting on something durable enough to not take damage (various types of armor, mostly), it's gonna lose.

I mean, you can say "the dog has ST 11 but big penalties on anything that actually uses ST", but that seems perversely complex. Also, realistically what matters for a lot of purposes (including weapon damage and wrestling) is actually torque, which is very simple: it's linear in mass.

Yep, and just make the point that German Shepherds bite harder per lb than humans do (which GURPS does).

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So OK a big problem with comparing different animals ST is that different animals even if pretty similar (e.g two mammals like dogs and humans) have different layouts in body form and musculature.

I.e dog don't exert force in the same way that humans do.

Put it this way even quite small dogs can exert a lot of force when pulling forwards against their owners, but they aren't going to win any arm wrestling competitions. because their body form favors the former action over the latter one.

[Tomsdad]

Originally Posted by Varyon

...
Interesting. That implies muscle strength is basically determined by fast-twitch fibers, but that effective strength has a lot of impact from leverage that my system fails to account for, and this is possibly a bit part of why mine has dogs being too strong. In fact, it seems arm length may play a rather significant role it determining arm strength, such that mecha (or aliens, or whatever) with SM+4 weight but SM+3 length arms may well have weaker arms than those with SM+4 weight and SM+4 length. Which... is pretty much the opposite of what I expected, and of the purpose of this thread. Huh.

The problem here is that arm length comes into effect at different points.

first off it comes into arm mass which you have been describing, and is factor of arm morphology and anatomy

but secondly the actual motion through which the strength is expressed can involve the arm (or limb in general) being a lever, and of course longer arms means longer levers.

[Infornific]

Originally Posted by whswhs

Human body weight may not actually follow the square-cube law. That assumes that you're scaling up all dimensions equally, which isn't necessarily the case within a species. Between species it fits better, though realistically I think having length vary as the fourth root of mass and cross-sectional area (and thus strength) as the cube of length comes closer to actual biological scaling, at least for animals that walk.

It's been a while but I remember checking records for various classes of weight lifters and the records tracked a 2/3 power rule surprisingly well. I might run the numbers again to be sure my memory isn't tricking me.