Is bonus HP for Con reasonable?

[Talakeal]

My friend and I were having a discussion about what house rules to use in an upcoming campaign and my friend said that there is little to no correlation between physical fitness or overall health and the ability to survive serious trauma. I said that surely can't be the case, but I couldn't actually find any evidence to support it one way or another.

Bone density and muscle density appeared to have some correlation, but age, gender, and genetics seem to be a far bigger factor there.

I thought that being in great aerobic shape would allow you to better survive blood loss, but apparently aerobic health is actually more about the shape and strength of your heart muscles than your body's ability to use oxygen efficiently, so I have no idea.

Anyone have any knowledge in the area or any data to provide one way or the other? Thanks!

[Grey_Wolf_c]

My friend and I were having a discussion about what house rules to use in an upcoming campaign and my friend said that there is little to no correlation between physical fitness or overall health and the ability to survive serious trauma. I said that surely can't be the case, but I couldn't actually find any evidence to support it one way or another.

Bone density and muscle density appeared to have some correlation, but age, gender, and genetics seem to be a far bigger factor there.

I thought that being in great aerobic shape would allow you to better survive blood loss, but apparently aerobic health is actually more about the shape and strength of your heart muscles than your body's ability to use oxygen efficiently, so I have no idea.

Anyone have any knowledge in the area or any data to provide one way or the other? Thanks!

I am not sure I understand the question. Constitution's purpose is to indicate the ability of a character to resist harm. If more HP makes you more difficult to kill, then constitution should give you more of them, yes. And for things that don't directly affect hitpoints -sickness, drowning, etc - then you get bonuses from constitution in other way.

"Physical fitness", if it is important to a character, usually falls under strength.

Grey Wolf

[Rogar Demonblud]

And the mandatory reminder that Hit Points are not meat points. Also, don't expect reality and D&D rules to have much if any overlap.

[Talakeal]

And the mandatory reminder that Hit Points are not meat points. Also, don't expect reality and D&D rules to have much if any overlap.

I think you might be taking the thread title too literally.

I meant this more as a general RPG principle than anything D&D related.

In the specific case that got me thinking about it we were debating whether or not to use the cinematic soak rules in a World of Darkness game, and I said it was a good real because without it a person in peak physical condition is no more likely to survive an injury than a frail bed-ridden ninety year old, and was told that this is a good thing because in reality physical fitness has almost nothing to do with the ability to survive trauma.

[tyckspoon]

If you're using 'cinematic' rules, you probably are working with Action Hero rules at the most realistic end of the scale - in that case, yes, being a tougher person means you can survive potentially lethal wounds better. If you don't want that to be true, you need to work with a damage/toughness/hp/wounds/whatever model that more closely reflects reality. For example, in a Wounds/Vitality system where Vitality represents non-lethal injuries and exhaustion, having a high Constitution or similar stat may give you more Vitality but not more Wounds - you have a higher pain tolerance and can fight through more light injuries and flesh wounds, your better aerobic conditioning lets you go through more strenuous conditions before you face exhaustion, etc - but when you take a real serious injury (as represented by taking a hit to your Wounds rather than Vitality) you're not any tougher than any other person.

[Grey_Wolf_c]

a person in peak physical condition is no more likely to survive an injury than a frail bed-ridden ninety year old

False (https://www.aarp.org/health/conditions-treatments/info-2018/broken-bones-death-risk.html)

Grey Wolf

[Florian]

I dunno. I was unfortunate enough to sign up to the army, get a training as field medic and be sent out there for our first war in decades. Seen a good share of broken and hurt people in that time.

Ive learned three things back then:
The ability to receive a hurt of any kind and still keep going is a mental thing and has to be trained.
Physics count only as far as we talk about minor hurts.
Dealing with a major hurt is more based on mental than physical attributes.

If you want to be more concrete, the watershed line here is between minor and major wounds. It makes a difference whether a bullet hits fat, muscles or bones. Not saying that a tip-top physical state doesn't help there, but it´s at the same time not as important.

[Lvl 2 Expert]

False (https://www.aarp.org/health/conditions-treatments/info-2018/broken-bones-death-risk.html)

Grey Wolf

Yeah, I'd say I'm much more likely to be okay after say a fall off a bicycle than the average 90 year old. Because I'm pretty much guaranteed to walk away from it and they could die.

Whether that quality should be under the same umbrella term as for instance running stamina, that's a very good question, but there is definitely some individual-bound factor to resistance to injuries. Since constitution is hardly an overused stat in your average 5-7 stat model I'd say it's probably fine to keep it there.

[JNAProductions]

The issue is not so much Con here as it is HP.

HP is... Nebulously defined at best, and a flipping mess at worst.

So, step one to this question: Define HP.

[LibraryOgre]

In Villains and Vigilantes, all attributes but Charisma contributed to your HP, to varying degrees. Biggest determinator was your weight, though.

[Tyndmyr]

Anyone have any knowledge in the area or any data to provide one way or the other? Thanks!

At one extreme, significant illnesses put one at risk. If you're immunocompromised, for instance, even fairly trivial accidents become very dangerous thanks to the vastly increased risk of infection.

Likewise, other health conditions, such as being overweight, can negatively affect a number of things. If you've been quite overweight for some time, in addition to being somewhat more likely to be sick, you're also more likely to develop joint issues, respiratory problems, etc. This will potentially exacerbate the damage from being beat up, in that it is more likely for your issues to compound and become very serious.

It's not perfectly realistic, in that it's a very general rule covering a myrid number of potential forms of damage, but that's the nature of HP.


a person in peak physical condition is no more likely to survive an injury than a frail bed-ridden ninety year old.

Y'see, that'd be an issue. Your bed ridden 90 year old, for instance, is going to be vastly more at risk from a fall than a healthy individual would be.

In fact, lower leg strength is an excellent predictor of mortality due to accidents in the elderly. Falls being damaging, the stronger and more stable they are, the less often they fall(Source: Health, Aging, and Body Composition, 2006). Even discounting the age factor, being in top shape is an excellent indicator of living longer.

Edit: While the effect appears to be strongest for leg strength, it appears solid for muscle mass in general, rather soundly contradicting your friend: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4035379/

[LordEntrails]

The issue is not so much Con here as it is HP.

HP is... Nebulously defined at best, and a flipping mess at worst.

So, step one to this question: Define HP.
This ^^ Plus what Grey Wolf linked about elderly health risks.

Does your system assume HP is only physical damage and resistance? Or does it take into account mental endurance and ability to overcome pain and have a strong mental outlook?

And finally, don't get too caught up in any of it. Remember, whatever game you are playing, you are playing a game, not devising a real-world simulation. Lots of things are done in RPGs to make them playable and enjoyable.

[Florian]

The issue is not so much Con here as it is HP.

HP is... Nebulously defined at best, and a flipping mess at worst.

So, step one to this question: Define HP.

HP as an abstraction of fighting spirits, morale, esprit de corps and so on is actually quite fine.

[Jay R]

Hit points are not reasonable. A thrust to one person's heart is as fatal as a thrust to somebody else's.

But if you are going to have hit points, then adjusting them for CON doesn't make them any more unreasonable.

[Grey_Wolf_c]

Hit points are not reasonable. A thrust to one person's heart is as fatal as a thrust to somebody else's.

It's an abstraction. A person with high pain tolerance and a healthy body might parry/slow down that thrust with their hand, exchanging pain for a death blow, while a lesser less fight-y person would not be able to perform that parry, and die. Since simulating the exact conditions of such fights would be terribly boring, we encapsulate the whole set of circumnstances into an easily trackable and understandable metric that allows the game to be played: HP.

HP will mean different things in different games and for different archetypes. The barbarian will have the above. The armoured knight will be more the ability to fight while sweating themselves to dehydration. The thief is more how much their ability to keep dodging survives a thousand nicks that would have put anyone else in the hospital or morgue. Etc.

Grey Wolf

[Ravens_cry]

You know a weird mix of in and out logic would be to think of HP as plot armour. The higher 'level' you are, the more the universe wants to protect you, since you're more 'important' to its story. A very Discworld way to look at things, I'll admit.

[Lvl 2 Expert]

Hit points are not reasonable. A thrust to one person's heart is as fatal as a thrust to somebody else's.

According to Cracked you have a 1/3 chance to survive getting stabbed through the heart (in modern times, but healing magic is if anything better than hospitals). I'm willing to bet the amount of blood you have, the speed with which new red blood cells are made, the strength of the immune system fighting off any infections etc matters for your individual changes. Granted, in that particular scenario a bedridden 90 year old might have the distinct advantage of losing less blood because their heart is weaker, but that will make it fail earlier as well.

Plus, you know, stabbing them through the heart is typically the end of a fight. In hitpoint logic you won't get a good stab at a good defenders heart until you tired him out, wounded his shield arm and slashed one of his Achilles tendons, and that's when they're at 3 hitpoints. They still do everything that's not defending their vitals with the same energy they had when healthy, but that's sort of a necessary abstraction against bookkeeping and for fun.

[warty goblin]

There are alternative systems that avoid quite a bit of the abstraction of HP, albeit with substantial bookkeeping overhead. The one that springs to my mind is the ancient and deeply weird mid nineties brain-breaker GateWar. It's been a while since I went through the character creation chapter, but basically you determine how big your character is, which determines the hitpoint totals for your head/limbs/etc, and the total amount of blood you have. Any hit causes blood loss (potentially ongoing) and damage to whatever location was hit. If you lose half your blood, you die. If one of your hit locations runs out of HP, you die.

Lest you think that this might actually be interesting, rest assured that the process of determining and allocating HP requires referencing like 6 separate tables. So far as I'm aware however, you do not get extra torso hitpoints if you are playing an amazon and roll for 'unusually large breasts' in the random amazon distinctive features table.

Basically GateWar is terrible is what I'm saying. Like a three way crash between a bus full of horny fourteen year old boys, a tour van filled with anal retentive accountants, and a truckload of AD&D manuals, you really do have to stop and stare.

[Telok]

I'm playing an interesting system right now. A bit more math than normal d&d but pretty good.

Hp are constitution + willpower with the stats on a scale of 1 to 5. PCs and major villains have 2x hp. All races have a size stat, from 2 for gnome/hobbit through 4 for humans, up to 6 for a sasquach or something. Size is used to determine resilence and defense. Defense being the to-hit target number as 10 + dexterity + wisdom - (size * 2). Resilence being size + level (1 to 5 range) /2, round up, then + 1.

Damage works as follows: determine the hit & hit location, roll damage (normally in the 12 to 48 range), subtract armor from damage (wearing a helmet is a good idea but armor tops out around 16), divide the remaining damage by resilence and round down, the remaining number is wounds taken.

Until you hit zero hp there are no negative effects. After you're at zero you stop taking wounds and start consulting a critical damage chart, that's where negative effects come in. It's effects are split by hit location and damage type, but crit 5 at any point is death. Notably crit 4 to the head also kills, and explosions will kill on crit 4 to the body or crit 3 to the head.

Unarmed attacks and many of the crit effects also inflict fatigue. Once fatigue is greater than constitution the victim is knocked out.

[warty goblin]

I've never understood the thing where games make larger enemies easier to hit in general. Easier to hit with arrows, slingstones and so on, sure, but probably much harder to hit with a handheld weapon if they're of a mind to stop you. By the time you get to something the size of an ogre, you're going to have to a lot of work before you can even get close enough to hit them at all, and without getting squashed in the process.

Which is really further argument for games having separate melee and ranged defenses.

[Algeh]

I've never understood the thing where games make larger enemies easier to hit in general. Easier to hit with arrows, slingstones and so on, sure, but probably much harder to hit with a handheld weapon if they're of a mind to stop you. By the time you get to something the size of an ogre, you're going to have to a lot of work before you can even get close enough to hit them at all, and without getting squashed in the process.

Which is really further argument for games having separate melee and ranged defenses.

I suppose this comes from the lack of separation of several different "ideas" about large creatures. I can think of 3 relevant ideas off the top of my head: Large creatures probably have more trouble dodging than small creatures, which should make them easier to hit. Large creatures probably have better reach than small creatures, which should make them harder to meaningfully hit. Large creatures should be easier to locate, which should make them easier to hit. In a system that didn't include dodging as part of HP, the reach aspect would probably be much more important than the locating aspect for melee, whereas the locating would be more important than reach for ranged. However, if we're including the concept of dodging, it seems like that would tip bigger enemies back in "easier to hit" again.

It's hard to know since so much of it depends on what kinds of assumptions your setting is making to even have much-larger humanoids, since that sort of body plan has some size limits in a realistic system that clearly aren't being applied in a fantasy system, so that probably also factors into things like how quickly they can dodge and what kind of reach they can enforce.

We could get very granular about a lot of this kind of stuff, but I question whether it's worth breaking all of that out into substats and portions of a combat turn for most games.

[Knaight]

Large creatures probably have more trouble dodging than small creatures, which should make them easier to hit. Large creatures probably have better reach than small creatures, which should make them harder to meaningfully hit.

Being bigger really doesn't make dodging harder - a single step taking you much further than it otherwise would when dodging is staggeringly helpful, and the same sort of thing applies to leaning out of the way in all of its glorious permutations.

[Chronos]

Maybe in games HP represent fighting spirit and morale and so on, but in real life, the model of them as "meat points" actually works pretty well. In the real world, we really do have things like high-level rangers getting their face shot off by a sniper rifle, or all the skin on their back being mauled off by a bear, and making a full recovery. Those guys weren't just really discouraged or tired.

[Morvram]

Yes. Regardless of whether HP is thought of, in the abstract, as being "plot armor," in most systems that feature a Constitution score, Constitution = Toughness. It would feel awfully inconsistent for a character with high constitution not to have more hit-points than a character with low constitution.

[Leewei]

And the mandatory reminder that Hit Points are not meat points. Also, don't expect reality and D&D rules to have much if any overlap.
This is largely how I explain the mechanic as well. If you can run a marathon, you can also duck out of the way that one last time when driven to exhaustion.

I'd add that Con->HP is not universal among RPGs.

GURPS now has fatigue based on Health and wounds based on Strength (i.e. bone and muscle mass).

FFG Star Wars has Brawn, which acts as both strength and constitution. Species also helps (or hinders) Wound Threshold in this system; Talents are by far the biggest contributor, though.