by E. Paul Zehr
Figure 4.2. The “inverted U” effect of physiological and psychological arousal on performance ability. With training, superhero Tony Stark is able to perform better and under more stressful environments than supervillain Obidiah Stane.
However, despite all manner of training and natural ability at managing stress and arousal, adding more stress to further increase arousal eventually leads to a decrease in performance. When attentional resources are at maximum, there can be increased errors. And piloting a hugely powerful armored exoskeleton loaded with weapons can be extremely dangerous. Let’s talk next about the extreme military adaptation of Iron Man encompassed in War Machine, the name given to the most highly developed military armor that Tony invented. This armor debuted in “Legacy of Iron” (Invincible Iron Man #284, 1992).
Figure 4.3. War Machine armor as shown on action figures representing a character in the Marvel Studios film Iron Man 2 (2010). Note the extreme militarization of the suit with shoulder and gauntlet cannons. Having this type of equipment built into the suit would make it difficult for the brain-machine interface to occur.
The gist of the story line is that Tony Stark is apparently dead and leaves a taped message for his trusted friend Jim Rhodes to take over the company and assume the mantle of Iron Man. But Rhodey would be using a new silvery gray armor—the so-called War Machine armor. If you want to get technical, the original armor for War Machine was called “Variable Threat Response Battle Suit, Mark I” and the version for Rhodey was “Mark II Model JRXL-1000.” I think it is easier to just call it War Machine armor for now. In an exchange that will have a lot of resonance for us later in this book, Tony explicitly explains to Rhodey that he “designed this last suit of armor specifically for you—to work with your own individual attributes, rather than mine.” Even at this stage of Iron Man, there was some concession about how the armor needs “tailoring” for each user. (However, this is not addressed like this in Iron Man 2. In that movie, Rhodey just jumps in the suit, slugs it out with Tony, and eventually flies away!) We will come back to this concept. The War Machine armor is basically similar to the “standard” (hard to really use that word considering how many versions of the armor have appeared over the years) armor but with a real nod toward armaments. Figure 4.3 shows an action figure of War Machine as portrayed in the 2010 Marvel Studios movie Iron Man 2. See the attached mini gun on the right shoulder and the double barrel cannons on each gauntlet. While it may seem like a small add-on to the suit, having these as integrated parts or attachments on the armor would create some problems with control later on. Will these weapons become part of Jim Rhodes’s body in the same way a prosthetic limb can? Or a suit of iron itself? And, does that hard suit of iron mean that the man inside gets soft? We deal with that in the next few pages.
CHAPTER FIVE Softening Up a Superhero
WHY THE MAN WITH A SUIT OF IRON COULD GET A JELLY BELLY
I’ll just stand if you don’t mind. I’ve got to do something about the flexibility of this armor when I get back to my lab … [Later, crushes a cigarette offered by Jim Rhodes (maybe he knew smoking was bad for you?)]—oops! S-sorry about that. I guess I haven’t got as much control over these gloves as I’d like.
—Tony as Iron Man describing problems with using the suit prototype, “Apocalypse Then” (Iron Man #144, 1980)
I have full mental control over the extremis armor—all the time. Even when it’s deactivated. The trick is to zero in on the control systems … One part engineering, one part inspiration.
—Tony Stark, in “With Iron Hands Part 3 of 4” (Iron Man: Director of S.H.I.E.L.D. #31, 2007)
No doubt about it, Iron Man’s armor is really cool. As I read the Iron Man comics over the years, I was always captivated by that armor. Then, the first Marvel Studios Iron Man movie rolled out in 2008, ratcheting up the gadgets on the armor. I like to imagine what a blast it would be to drive. Or wear. Or ride. Or merge with? Er, you know what I mean. Before you start building such a suit for yourself, we ought to discuss a few problems that might be created by throwing something as complex and sturdy as an armored exoskeleton on top of your trusty human body. First, since you already have a skeleton inside your body, putting on an exoskeleton means you would have to deal with two skeletons. That would create some real challenges in getting around! All throughout your life, your body has been well calibrated for how big you are and how your body moves. Second, wearing a suit such as Tony’s would affect your ability to walk properly for a while after you took it off. Third, let’s also not forget how uncomfortable wearing it would really make you feel. Rather than soft pliable clothing, your skin would be covered with layers of metal.
Next consider how that suit would affect your body temperature. Scientists call this “thermoregulation,” or the ability to adjust your body temperature within a normal range. Kind of like a room temperature setting for your internal organs. Well, all the systems that affect body temperature are well suited (all right, pun intended!) for you when you are not wearing a huge metal suit of armor. Putting one on and then doing an extreme amount of exercise is likely to feel quite warm. (If you recall, that was my daughters’ objection to wearing the armor. It would be too hot!)
Some of the issues Iron Man has to consider are pretty similar to those for deep-sea divers, firefighters who wear heavy and very hot protective gear, and astronauts. We will look at all these potential effects of wearing the suit and more in this chapter.
It All Depends on Your Underarmor
Wearing unpowered, that is, regular armor, would be really fatiguing. And awkward to move around in. This point was brought home to me quite clearly while writing this book. I had just watched (again) the fantastic Lord of the Rings trilogy on DVD. This time I also watched the special features on the third disc in which the actors are interviewed in the “Weta Workshop.” Karl Urban, who played Éomer, said that when he first put on the armor “I went to walk and I just about keeled over. I was just so unused to the sheer weight of the costume.” He also said that “once I put it on I was loath to take it off because it was quite a process…. Going to the toilet was fun … trying to fit into those small “port-a-loos” when your shoulders are 10 feet wide.” (Despite its importance, we aren’t going to touch on how Tony Stark goes #1 or #2 when he is in the Iron Man suit.)
Let’s think about this further by using an issue I introduced in Becoming Batman: the effects of stress and physiological adaptation on the body. The body attempts to adapt so that the stress has a minimal effect. In Becoming Batman, I wrote about the stresses needed to produce Batman, stresses over and above what we would normally experience in our daily lives. Here I want to talk about the opposite: what happens if you remove the stresses? That is, imagine what would happen if we had fewer physical stresses on our body than normal. The bottom line is that our body systems work in a very predictable way when it comes to adaptations to stress. This means that removing the stresses also leads to a reduction in the benefits that occurred when the stresses were present. If we do exercise training that leads to stresses on our muscles, they get stronger to compensate for the stress. The reverse scenario is maybe a bit harder to grasp.
Iron Man Puts His Feet Up
A way that the effects of decreased use have been studied is to use bed rest. Yes, this means literally resting in a bed—as did John Lennon and Yoko Ono—for many weeks at a time. Prolonged bed rest doesn’t remove all the effects of gravity—which provide crucial stress cues for keeping many physiological systems working well—but it does lead to an overall reduced activity level. The idea of using bed rest in people to study the effects of decreased use of the body came from work in other animals, such as the rat. Overall, there are some clear effects. The neurons in the spinal cord that make muscles work behave differently and are more difficult to activate than in an active animal, the protein content of the muscles decreases, and overall force output declines. At the same time, the cardiovascular system also degrades, so the amount of muscle energy a
nd the ability to move are both reduced. I have highlighted a bit about what this would mean in figure 5.1. The first column lists different systems (e.g., muscle) or specific items (e.g., reaction time) and then the effects of either being generally physically inactive or undergoing prolonged bed rest, spaceflight, or habitual use of Iron Man armor. The important thing to note is the effects of using Iron Man armor shown in the far right column. The overall effect is universally decreased function, with a startling result: using the Iron Man suit to enhance ability leads to a decreased functional ability of the human inside.
Figure 5.1. The severe deconditioning effects of prolonged periods of wearing the Iron Man armor on Tony Stark and many of his body systems would be similar to those seen during bed rest, reduced physical activity, or prolonged spaceflight.
Out of This World
Probably the best, and most relevant, example to think about, though, is the literal “out of this world” experiences of astronauts during spaceflight and while working in space. Many of the stresses that help maintain the density of our bones and the strength of our muscles comes from the direct and indirect effects that the force of gravity has on us. When astronauts and cosmonauts are on long-duration spaceflights, they are working in an environment where the force of earth’s gravity is essentially completely removed. This means that the stresses are removed, leading to weaker muscles and lower bone density. There are also problems in processing of sensation occurring during movement. The end results are overall weakness and reduced ability to coordinate the body, including the arms and legs. This can be seen in the plots of movement shown in figure 5.2, which shows how movement or position of the head is coordinated with the body (the trunk) before and after spaceflight. This tight coordination is seen by the close clumping together of all the points before spaceflight. In contrast, after spaceflight, there is much looser control between the different parts of the body. This can be seen by the much larger area covered by the plot in the diagram on the right.
Figure 5.2. Using the Iron Man suit of armor for extended periods could disrupt normal bodily coordination. The left panel shows angle-angle diagrams for movement of the head and torso in astronauts before spaceflight. Note the tight and small area of the plot, which means very good coordination. The right panel shows the same concept plotted for astronauts (and implied for Iron Man) after prolonged spaceflight. The coordination is much weaker. Data redrawn from Paloski (2000).
Wearing the Iron Man suit for prolonged periods would also give rise to this lessening of control of how your body would move. This means that when Tony “doffs” the suit, he better not have to do anything that requires really good coordination right away. In the case of the Iron Man suit, the effect should be fairly short-lived and represents something called an “aftereffect.” Remember the example of my running on the walkway in the airport and then the jarring experience of my landing on the hard tile surface from chapter 2? The effects of wearing the suit on Tony would be similar.
In addition, the effect shown in figure 5.2 gives an indication of how someone can respond to a perturbation. Most of your motor system responses, even if you don’t pay attention to them, have to do with correcting body movements when there is an external perturbation. Think about riding on a subway train or a bus as an example. When the train moves, its motion causes a sway on your body. This is a perturbation. If you don’t correct for the perturbation, you step or fall. The figure here shows how the chance of not correcting properly to a perturbation after spaceflight is greatly increased.
Enter—the Jelly Bellied Avenger?
Wearing the Iron Man suit of armor for long periods could be very much the same as the effects that would result from prolonged periods of being in space. This is where the “jelly belly” part of the title for this chapter comes from. Being in that suit would lead to extensive physical deconditioning. Especially in the later models, Tony is propelled into the air by turbines in his boots and external motors in his armor make him move. Since Tony Stark’s body is in that suit, his arms and legs don’t have to do much work anymore. This is why his experience is like being in space, where the reduced gravitational effects mean lower forces and less effort is needed for movement.
The force of gravity is seen as the acceleration of objects when falling (or being pulled). At sea level, this force is trying to accelerate objects at 9.81 meters per second squared, faster than many sports cars go from zero to 100 kph (60 mph). This may seem dramatic, but even while you are sitting reading this book, earth’s gravitational field is trying to make your body (and the book, too, so please hold on) fall toward the center of the earth. Fortunately, this gravitational field is countered by the activity of your muscles. Your muscles act to maintain your posture and movements, and your bones are affected to maintain their mineral density and strength. The stresses induced by the gravitational field (and your movements within that field) that strain your muscles and bones help keep you the person you are.
Without that, you would become deconditioned. Your body must also work against the inertial aspects of your body. That is, different parts of your body have different masses, and any movement you make has to work against both the desire for that part of your body to stay at rest (or in motion) as well as the constant gravitational field. If you take a two-month visit to the International Space Station, you greatly remove these effects. As a result, you lose things like strength and bone density. This was recognized as a major issue for spaceflight and a large area of research into “exercise countermeasures” while in space has developed. Astronauts must do lots of exercise and working out in order to maintain their bodies as best as possible. It’s basically a case of use it or lose it. But not losing it in space remains a major challenge.
If you exercise on earth, you are usually going to get in “better” condition. But if you exercise in space you are usually not going to get in “better” condition. Rather, you will at best maintain (but usually not really) or reduce the deconditioning effects. While sporting around in a robotic suit that moves his body for him—that is, the Invincible Iron Man—won’t remove all the forces acting on Tony Stark’s body, it will drastically reduce the impact of them. Extensive deconditioning of Tony’s body can be expected, and he needs a rigorous exercise program to maintain himself. Or he really will get a jelly belly. With so much assistance to move, he actually would wind up doing less!
Rehabilitation Robots
Sadly, despite a childhood desire to be an astronaut, I was never able to experience being in space orbiting the earth. Sigh. However, I have walked around in a robotic pair of pants! This experience gave me an insight into how Tony might feel walking around in his suit and how disorienting it might feel to take it off again. In earlier chapters, we saw that prosthetics help people who have lost limbs and neuroprosthetics help people when there is damage to the nervous system such as after a stroke, blast-related head injury, or spinal cord injury. In such cases, there are often many problems with being able to make normal movements, such as using the arms in tasks like reaching and using the legs during walking. Very recently neurorobotics has sprung up as a specialized field in which powered exoskeletons for assisting arm and leg movement are being used to help move the limbs with external devices. Recall these are assistive devices, well, because they assist with movement. If you have problems with movement, these neurobiotic devices provide important help. But if you can already move and have a robot amplifying your movements, it also does most of the normal movement for you too!
Starting with the shrapnel in his heart in his origin story, Tony Stark has had several health crises over the years that have resulted in his needing assistive devices. One example is in a story arc spanning Invincible Iron Man #242–245. In “Master Blaster” (Iron Man #242, 1989), Tony returns from a battle in which Iron Man once again defeats his nemesis the Mandarin. However, now as Tony Stark and wearing no armor, he is surprised to find his former girlfriend Kathleen Dar has broken into his apartment. She pull
s a gun and shoots him in the chest in the last pages of that issue. We find out in the next issue and the story “Heartbeaten” that Tony is not killed by the gunshot wound but is left with a spinal cord injury. In the words of his attending physician, we learn that “the bullet’s passage destroyed vital nerve tissue along the spinal column … Damage that even with today’s technology is irreparable. As a result … Tony Stark will never walk again!” (By the way, I have to interject here and state that, in my opinion as a neuroscientist, all nerve tissue is vital.)
When it comes to walking and movements of the legs, a couple of devices that you can buy—almost off the shelf—are the ReWalk and the Lokomat. The ReWalk is one of the new kids on the block for commercial robotic prosthetics. It is made by Argo Medical Technologies and is a programmable robot that can be set to produce standing, stepping, and other basic movements. Lokomat is the name of a robotic assistive device produced by Hocama in Zurich, Switzerland that is basically a set of exoskeletal “pants” worn by someone and falls in the category for use in a kind of therapy called “body-weight assisted treadmill training.” Using a complex computer controller and a series of motors that can move the legs, the Lokomat can produce stepping and walking patterns. The point of devices such as this in clinical use is to help people who have had a stroke or spinal cord injury retrain their walking pattern. After damage to the nervous system, overall muscle weakness is quite common. The Lokomat is used in walking to help support the body and then to move the limbs in patterns that are like walking.