Increasing muscle power without increasing volume

Question

Some of you may know my mutant thread, and guess what? It's back.

I'm wondering if there is any biological means to improve muscular power without greatly increasing the volume of said muscle.

My conundrum is that I have some mutants easily able to lift 6 tons (and more - as in lift above their head and carry around), but that look like normals, albeit athletics, humans. On the other hand, the human world record for bench-pressing is around 320kg¹ and the holder is already humongous.²

Is there any way (apart from handwavium) to increase muscle power and retain a normal human shape?

What I'm looking for/How I'll rank answers:

• Only biological, science-based explanations please. No mechanical augmentation, something that can reasonnably happen inside a "human-ish" body (so please, no nuclear fusion to power your super muscles).
• The energy expenditure is overlooked, but other factors such as resistance (to avoid this person tearing itself up) would be nice.
• If it's not possible, explaining why would also help.

_{1: From the top of my head, feel free to correct me if there is any mistakes.
2:And yes, Batman bench-pressing 1-ton is clearly inhuman, stop pretending this guy is not a mutant in some way.}

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Addendum: Of course, lifting capacity does not equal strength. But it is hard to exactly describe the physical raw power of someone. Lifting is used here as a common denominator for everyone to just show the order of magnitude involved.

Answer 1

Yes, there is likely a way, though I will admit I'm not sure how much of the desired about 20x difference it will get you. By the time you get into those mass ranges, the strength of the bones, tendons and attachments will likely be as important as, if not more so than, the muscles themselves. Also, as Spoki0 pointed out, technique matters.

That said...

Give them more fast-twitch muscle fibers, and less slow-twitch ones.

See for example How chimps outmuscle humans.

Slow-twitch muscle fiber (myosin heavy chain I) are better for endurance tasks, while fast-twitch muscle fiber (myosin heavy chain II; in the case of chimpanzees, specifically type IIa and IId) come at a higher energy cost and are better for speed and short-term force. As stated in the linked article,

The researchers found that whereas human muscle contains, on average, about 70% slow-twitch fibers and 30% fast-twitch fibers, chimpanzee muscle is about 33% slow-twitch fibers and 66% fast-twitch fibers.

By running simulations, it was found that this difference of slow-twitch vs fast-twitch fibers resulted in an overall muscle which was 1.34 to 1.35 times as powerful, depending on the exact metric. The researchers performing the study concluded that

These results suggest that the larger fraction of MHC II fibers and the longer muscle fiber lengths characteristic of chimpanzee skeletal muscle will increase their dynamic force and power-producing capabilities overall.

and that

Although our simulations do not reproduce the earlier experimental designs in detail, the close approximation of our results to the 1.5 times average suggests that muscle mechanics—MHC isoform content, in particular—accounts for much, but not necessarily all, of the measured chimpanzee–human performance differential. Muscle “static strength,” defined as maximum isometric force-producing capabilities (P_o), is not significantly different between these two species and therefore does not contribute to their performance differential[.]

Therefore, it stands to reason that by tweaking the muscle fiber composition to favor type II, and by increasing the length of individual muscle fibers, you can increase muscle power without a corresponding increase of muscle volume, but at the cost of muscle endurance.

As pointed out in a comment by Yakk, you can also take this even further by giving them even faster and longer muscle fibers than humans' long type II muscle fibers. You will hit a limit at some point, but as pointed out, it's definitely possible to give your creatures even more strength per unit muscle mass than humans' type II fibers allow, and you can probably maintain suspension of disbelief taking it at least one step further, though again, you're making a tradeoff against endurance.

Answer 2

Strength and muscles

Strength does not inherently correlate with muscle size.

Increasing your neural activation, that is, simply utilizing more of the muscle fibers, can greatly increase your strength without the fibers being significantly larger. Certain people train specifically for this, ex. sprinters, as the increased mass would slow them down again.

That's not gonna get you to lifting 6 tons by itself, but could be a starting point. Very efficient neural activation.

Not all muscle fibers are equal.

Different fibers are specialized at different things. Think heart vs. pecs. While it is very specialized, the estimated bite force for a human is around 135kg. The related muscle is much smaller than other muscles typically associated with those numbers.

While I don't know of any existing muscle fibers in nature that would scale up to 6 tons of lifting in a human, that could be something to explore.

Bones and tendons

As mentioned in another answer, there is more to lifting than simply your muscle. Bones and tendons might not be able to cope with the forces. You wouldn't want your guy grip something hard, and have the tendons to his fingers snap from the force, leaving him unable to grip for the future.

Therefore your chap would need some solid upgrades to his bones and tendons, to prevent the muscles from destroying them with the forces exerted.

Lifting and muscle strength

Lifting strength does not inherently correlate with muscle strength.

Many who do weightlifting notice that if they get proper form, they can lift more. Typically this would be because they are better balanced or activate supporting muscles that help during the lift. It is also safer and better for your body.

That's more of a heads up that even if your guy is super strong, he wouldn't inherently be able to lift super heavy. He might be limited by form, or even hurt himself due to the lack of it.

He'd still beat everyone at bench press though...

Answer 3

There have been good answers about fast twitch fibers and better neural activation. Both of those are good but the reason we have slower muscles and why our bodies only activate as few muscle fibers at a time as we do is that both of those are very energy intensive.

So, aside from better bones and tendons, the mutant needs to get oxygen and more (or better) nutrients to the muscles. This can be as simple as better blood flow to the muscles to as complex as completely redesigning the chemical energy system used by the muscles.

Answer 4

I'd look into the phenomena known as "Hysterical Strength" which occurs in humans in the real word. Basically, while the exact source of the adrenaline is not fully understood and the very nature is nearly impossible to test, during periods of hyperarousal (aka Fight-or-Flight Response) the surge of Adrenaline in the human body can allow an average person the strength to lift in excess of one ton (there is a case of two teenage girls lifting a farm tractor off their father who had been pinned under it.).

This occurs because under normal conditions, the human body only twitches (muscle contractions) about 1/3rd of the muscle fibers for any sustained muscle contraction. Adrenaline causes more muscle fibers to twitch (when a muscle fiber contracts it will eventually release. If a contraction occurs a second time before the release the output of power of both contractions are added together). This occurs without any increase to muscle mass or amount of movement of a normal human.

You could explain your character(s) mutation as having the ability to willfully release enough adrenaline to trigger a state similar to Hysterical Strength and while 6 tons+ seems excessive, again, given the situations are usually life or death triggered, it's not known just how much a human can lift under such conditions. This would also prevent your character from a situation of no knowing their own strenth as they'd have to be in this state to be superhuman. There is an actual reason why Humans don't permanently use all their muscle fibers as the mechanical forces of such a state have resulted some people suffering muscle tears from the increase. Humans are actually one of the most densely muscled apex predator mammals in the world, with only Lions, Tigers, and Three Species of Bear having a higher average body weight than a human (Including the Polar Bear, which in another documented Hysterical Strength case was held off by a Canadian Woman buying time for a group of people to escape to safety and a park ranger to retrieve a rifle and kill the animal.). Using the remaining 2/3rd of the muscle fibers in our body would be the equivalent of having an oxygen mask on a commercial jet: You don't need it when things go right, but you'll want it when things go very wrong.

Answer 5

I don't think it is possible, unless "nuclear hyper ancient magic, something".

A ten-to-twenty-fold increase may seem counter-intuitive to start with, but that's actually within the realm of "possible". You can get that on normal people with electro-stimulation, so why not naturally on some presumed mutant, if you are willing to handwave a tiny little bit. But the problems are of different nature.

First, while increasing strength (muscular "power") is possible without increasing mass, and while increasing strength endurance alone is possible without increasing mass, increasing both at the same time is impossible (without increasing mass). Your mutants are to lift 20 times as much, and carry that around, so they need both.
Increasing actual muscular power (just to be nit-picky on wording) would require a combination of things, including a fundamental change to your cardiovascular system. Power is energy-per-time, and 90% of your energy comes from the electron transport chain in your mitochondria. Which requires, well... oxygen, and not precisely small amounts. So you need huge quantities of blood flowing through your muscles to supply that oxygen, which is already a practical problem on a contracted muscle of "normal" strength. Now, multiply strength by 20, and you multiply the supply problem by 20, too... Unless you are happy with 5-10 second feats (question explicitly says different), you're kinda lost.

You can activate more muscle fibers at the same time, that's what people who do strength training learn to do at will. It's what most animals (including e.g. apes) do, too. Animals are not magical in any way, they're just not as much of a wuss as the average human because in the real world in which they live, being a wuss means being dead and eaten.
It's more neurological than actually "muscle". Also note that the guy holding the world record in bench press is not necessarily the strongest guy, either. Or the biggest, for that matter. Some stunningly strong people are surprisingly small and slim. Think e.g. Chinese acrobats. The thing is, the more fibers you activate at one time (for more strength), the more fibers get tired (pretty obvious). Which means unless you have more of them, you necessarily have to drastically reduce time.

Second, assuming you can actually increase muscular strength to that level, it would almost certainly mean that your tendons would rupture. Tendons, vaginae, and hypomochlia have to endure surprising amounts of force even for trivial tasks. In hand surgery, one is often surprised why they make such a darn fuzz about holding fingers in some particular position with rubber bands for ages after suturing. Well, the reason is that merely moving a finger will put the equivalent of around 20 kilograms on that little tendon, which is non-trivial for a healthy tendon already, but definitively is more than the suture will support. So imagine what forces are at work when you actually grab something firmly. The force that acts on the various fibrous rings that keep tendons in place and allow them to force the attached bone in some particular predetermined direction can be 10-20 times as much. The forces on your knees or elbows when the joint is in a widely-flexed position? The knee at least has the patella, which somewhat redirects force in a sensible direction. The elbow doesn't. Don't even want to think about how much force acts on that tendon.
Although we're looking at some of the strongest tissues nature is able to build, in reality it often comes close to what the tissue is able to physically support. That's why repetitive strain wears stuff down so surprisingly fast, and it's why there's not rarely... BANG... catastrophic failure.´. So, well, OK, they're mutants, let's assume they have some magical carbon-nanotube tendons, whatever, which magically support 3-5 times as much. But we talk about multiplying with 20, and not just for a second or two, but supporting that for a lengthy time, I cannot imagine it could work.

Third, there's levers at work. For example, your spine is one huge lever (about a meter long) connected to some small levers (about a centimeter or two). Plus, spinal discs, which are surrounded by a fibrous ring. The disc itself is pretty much indestructible as long as it's held together, but the ring isn't...
The actual force depends on where you look at, but let's just assume there's a ten-fold increase (which is very optimistic). Lift 50 kilograms, so you effectively have 500 kilograms acting on your little piece of bone or your fibrous ring, there. Now you want to lift 6,000 kilograms... good luck. A small piece of innocent bone less than a centimeter thick just cannot support 60 tons sheer. I am not sure if a piece of solid steel would, even. Similar is true for virtually every bone, to a different, individual extent.
Note how e.g. when people die from tetanus or are exposed to electricity, muscles often do break bones. This is not just an idea, it actually happens.

Answer 6

6 tons -- Not possible without completely different substance

As other answers have mentioned, there is a host of problems with moving around 6 tons with a normal human frame. Several biological, but also fundamental chemical/physical problems. The amount of pressure and forces which will need to be generated need a lot of chemical energy, need to be sustained and need to be transferred by tendons and bones.

The only possible way I see is a completely different, to us unknown chemical composition of mutant bones, tendons and muscle fiber. The bones need to have a composition with at least 20-times structural stability (something with carbon nano-tubes?). The tendons need to have at least 20-times tensile strength (steel wire could barely provide this with about 200 N/mm2) and then you would need muscle-fibers with a different and 20 times stronger power of contraction than out ATP-powered muscle fibers, but with similar regenerative properties. As far as I know this would need to be complete handwavium, because I don't know of any fibers/reaction with properties even in this ballpark. And finally the whole digestive-tract and cardio-vascular-system would need to provide these fibers with enough resources so they can actually keep this up, this could mean a completely different type of lungs and diet for you mutants.

TL;DR: Still calling these mutants "human" is probably a stretch, because they would be more like synthetically designed beings with a human shape.

Answer 7

Today I read about a carbon fiber which can lift 12'600 times of its weight.

A mutant could grow a few such fibers or similar inside their muscles. Note that they also would need stronger bones, this means perhaps a different type of carbon fiber inside the hydroxylapatite structure of the bones.

Answer 8

First you would need to define what is "lift". Because I would say that Eddie Hall 500kg is current record.
And with that segue - Eddie in talk with Brian Shaw (another strongman) talked about mental blockade of lifting heavy. That humans can lift even more (anecdotal sample of mother lifting car to save baby) but the brain is preventing them to do that to save from destroying their body (which is very easy as mentioned, both Shawn and Hall, have snapped their biceps. They have literally torn their muscles from bone it was attached to).
When lifting heavy, strongman often sniff ammonia to override part of that blockade.
Eddie Hall talked about sessions with psychologist to overcome that issue. Also how he lifted that 500 kilograms by "being somewhere else". So mental work is more important than physical one.
What would be the biggest enemy of "no more volume" is the bone density. Pulling would relay on muscles and tendons but pushing would also require bones (in first, you use rope, in second a piston). That's the reason why strongmen pull trucks and not push them. The bone might not be able to withstand the force that 6 tons would act upon them.

Answer 9

Material for handwavium:

1. The fibres don't require energy for holding still. Thus you could do a chin up, stop half way, and hold it indefinately.

2. The fibres have a ratchet mechanism. This relates to the above, but it means that you can amass the energy for one notch of the ratchet, move that notch, and rebuild.

3. The fibers have an energy recovery system of X% efficiency. If you think of them as being motorized springs, reversing it may allow them to be motorized generators.

4. Your bones, ligaments, tendons -- skeletal infrastructure are made from carbon nano-fibre or amorphous diamond (Muscle fibres made of bucky balls on nano-fibre for the ratchet?)

These three items give you great strength but normal power. (Power = energy/time = force * distance / time. Strength = force)

5. Your body has a way to store some kind of oxidizer in tissue. Probably not as efficient as air plus hemoglobin -- you have to spend energy to do the storage. This gives you a short sprint period. In addition, each cell can store more glycogen than presently store either as glycogen or glycerol or similar compound.

Some numbers: Normal activity by a person sitting around is ~75 watts. Long term endurance events are typically a few hundred watts. How big 'few' is depends on your training and talent. Sprint events can be ~1 kilowatt.

Let's suppose that this chemical allows 10 times normal powers for a while. So your typical 80 kg hero can burn at 10 kW. 80Kg body equates to about 50 Kg water. 10 kW = 2.5 kcal/s = 150 kcal/min. So Our Hero's temp is going to rise about 3 C per minute, if he's going flat out aerobically. Few people think clearly with a temperature of 42 C (104)

Ok. We have to postulate another chemical reaction internally: This is one that absorbs heat. This might be able to double or triple the above time.

Human metabolism isn't a very efficient one. About 75% of the energy you eat is spent as heat. Some is transferred directly to the environment. Most is used to evaporate water. If you can double the efficiency, you get 6 minutes instead of 3 minutes.

You can also stretch it by getting wet ahead of time. Evaporating of water uses some 500 kcals/kg -- about 3 minutes worth of total heat production Picture your Flash doing a shoulder roll through every large puddle as he goes along.

Working at 10 times the power doesn't mean he can run at 10 times the speed. There natural paces depending on leg length, arm length etc. There are also limits to traction. His rapid travel pace may end up looking more like a superball thrown hard.

Of course it's not all running. If he's doing stuff that normally doesn't get him breathing hard, he can do it faster. Now the overheat problem becomes merely local muscles. A well developed circulation system can help distribute that heat.

A flow through lung would help, both to avoid use of his stored oxidizers and to cool. With flow through you should be able to double the O2/CO2 exchange rate.

Answer 10

You could start by being a woman :-)

Seriously, a woman can build strength without developing the buldging muscles of the stereotypical bodybuilder. Those are really down to testosterone: the only (or at least the main) way that women get them is by using steroids.

Then you can try being a chimpanzee or orangutan. They're anywhere from 2-6 times stronger than a human, without buldging muscles.

Still, I doubt that you will get anywhere near to lifting 6 tons, much less carrying it around. The reason is that the materials of the human body - bones, tendons, and the attachments of muscles to them - simply won't take that much strain. Even with what normal/athletic humans can lift, it's perfectly possible to strain muscles & rupture tendons.