Sometimes I read about daily/martial encounter powers, and often the argument "It's immersion breaking!" or the more specific "It's not realistic!" comes up:
"If a fighter can do that, why can't he do that ALL THE TIME?"
The first point is fairly easy to argue:
1) narrative, this is when the spotlight shines on you. When Conan swipes off the giant snake's head in a single blow, Robert E. Howard was using his PC's Daily. It's the PC using his own token of agency to affect his fantasy world.
2) 'realism'. I don't really want to use that word for Fantasy Dragon Dungeoning... but crazy athletic feats can get pretty tiring. Hitting a monster 9x harder than you normally can is one of those tiring things.
When arguing with someone and trying to change their mind though, it's good to have proof, so this thread is about some 'proof'. I remember reading something about how human muscles use 3 energy sources, the time it needs to recharge for peak performance, etc. (I'm a mixed martial arts enthusiast and was looking at training routines)
So I did a little research and found it again. It's about the 3 kinds of energy our muscles draw from and their limitations.
Highlights on the parts relevant to the topic.
Three systems produce energy in the human body, one aerobic and two anaerobic. They are:
· ATP/CP system - anaerobic.
· Lactic acid (LA) system - anaerobic.
· O2 system - aerobic.
The ATP/CP system.
It is anaerobic because whilst using it, oxygen is not supplied from the air breathed in. Adenosine triphosphate (ATP) is a compound necessary for muscular contraction. The compound is stored in the muscles and a very quick contraction, lasting only a fraction of a second uses it all. For an exercise lasting longer than this, another compound called creatine phosphate (CP) is used. CP can provide a muscle with virtually instant energy without the need for oxygen. It is the muscle's emergency system, but it is stored in only very small amounts and so is depleted very quickly.
In an untrained person ATP/CP is exhausted in about 8 seconds. Through proper training it can be made to last only a few more seconds. Anything requiring short bursts of energy at maximum intensity relies heavily on this system. (like an encounter or daily power)
It takes about three minutes of complete rest to get a fairly full restoration of ATP (so, once per encounter). Proper training to maximize ATP/CP would be short bursts of 15 seconds or less at maximum intensity, with rest periods between short bursts of three minutes or more.
2. The lactic acid system (or the anaerobic lactic system) - LA system.
This system can also supply the muscle with energy in the absence of oxygen. But it uses glycogen and because of the lack of oxygen, lactic acid is formed. Intense activity of a muscle causes this system to operate at a high level until eventually the build up of lactic acid inhibits the muscles action and causes it to slow down. The blood system removes lactic acid to the liver where it is detoxified. During a recovery period the muscle regains its ability to function. The period of time that the muscle can support this type of effort is up to two minutes. An example of an activity of the intensity and duration that this system works under would be a 400 m sprint (or perhaps an Encounter with a dragon)
3. The aerobic system (O2 system).
This system utilizes breathed in oxygen in the muscle and thus interacts with the cardio respiratory system. The presence of oxygen in the muscle allows stored foodstuffs (mainly glycogen but also protein or fat for very long duration exercise) to be transformed into muscle energy by a series of reactions which avoid the production of lactic acid. The O2 process can therefore continue for as long as the energy demands of the muscle are within the capabilities of the oxygen delivery system and the food store. Lactic acid may well have been built up in previous work bouts because the LA system may have been used first. But in this case transferring from the LA system to the O2 system will allow the lactic acid to somewhat dissipate.
This can be used to explain the difference between an At-Will and Encounter power.
So we could say a 100meter dasher is somebody with a movement Encounter/Daily power
a 400meter runner is someone who has an at-will movement enhancing power
a marathon runner has skill training Endurance or some other power that enhances daily travel limits.
As for dailies, well note that even with a 3 minute rest you don't get absolutely 100% restored, nor is strain removed. Athletes have some pretty intense, lengthy recovery processes after games like massages and ice baths. The body can only take so much strain, and will fail when pushed too far (For example, power lifters have been documented crapping out their intestines when their bodies can't take the strain of the weights they're trying to lift). There is also mental fatigue to consider.
Ask any physical trainer though, and they'll agree the important part of recovery is to get a good night's rest.
*(In something as stressful as combat sports, it's often months before the fighter's next match to make sure they're close to peak performance)
I'm not saying '4e is completely super realistic', but there is some real-world relevance to how it goes about things. If it helps in the immersion of your fantasy dragon murder-looting, then enjoy.