Monthly Archives: September 2018

The amazing placenta: why you should do public engagement

By Emma Lofthouse, @Emlofthouse, The University of Southampton

I have taken it upon myself to spread the word about the brilliance of the placenta. It’s a fairly tricky task but someone has to do it.

Like all public engagement, this is a two-way dialogue that enables mutual learning between scientists and the public. It both fosters understanding, while providing an opportunity to discuss opinions, questions and concerns in an interactive way.

I created an interactive game called ‘the a-MAZE-ing placenta’, a game of physical skill that demonstrates the complexities of pregnancy and the many roles of the placenta in growing a healthy baby.

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The object of the game is to tilt the placenta maze to guide the ball (representing nutrients) to the centre of the maze (the umbilical cord) in the fastest time possible while avoiding obstacles. These represent pregnancy conditions and risks: a ‘smoking forest’ traps the ball, toxins and infections block the path of the ball, and pre-eclampsia makes the ball hit dead ends or narrowed pathways.

During the game, we talk to both parents and children about the Developmental Origins of Health and Disease hypothesis, which suggests that the conditions we experience in utero can impact our adult health and relate this to the obstacles in the game.

Through pick-up on Twitter, ‘the a-MAZE-ing placenta’ has since debuted at conference,; open days, country shows, science festivals and schools.

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Public engagement is now strongly encouraged in the research community with many funding bodies requiring public engagement activities as a condition of research grants. Outreach has great benefits for the public but just as many advantages for the scientist. It provides an opportunity to improve your communications skills with all types of audiences and gives you the opportunity to inspire someone.

Many researchers realise the importance of public engagement but are unsure of how to get involved. However, by simply talking to friends and family, you are already sharing your research and encouraging people to consider the relevance of science in their every day lives.

If you are looking to get involved with outreach, have a look at the opportunities that The Physiological Society provide including public engagement grants, Physiology Friday, the public engagement toolkit and ‘I’m a Scientist, Get Me Out of Here!’.

You can also become a STEM ambassador. Their events are designed to educate and more importantly, inspire young people to continue with STEM subjects at school and to help open their eyes to the careers that are available to them.

Top 10 Tips for Science Outreach

1. Keep it simple: Whether you want to share your research and passion for physiology, or promote The Physiological Society, the best thing to do is stick with a simple idea. It could be a free public lecture, a physiology pub quiz or even a stall with Society merchandise and leaflets. We’ve developed free outreach activities for you to use (or adapt to your own research), an you can also get inspiration from our case studies of events.

2. Decide on your audience: Is it undergrads studying physiology as part of their degree, the general public or school students? Our primary target audience is 16-25 year olds; we want to inspire the next generation of physiologists.

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3. Decide on a location: Depending on who you want to reach, this could be at your University, a school or somewhere in a community such as a library or shopping centre.

4. Contact your Society Representative: If you have one at your institution, get in contact with them as they may be able to help you with planning and have access to Society banners, magazines, and fliers to use at the event. If you don’t know who your Society Representative is or if you have one, please get in touch.

5. Recruit lots of helpers: Reach out to friends or colleagues for a helping hand. If you have your own students, try to get them involved and running the event. Anyone can organise an event on Physiology Friday whether it’s undergraduates, PhD students, postdocs or lecturers.

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6. Get funding: Approach The Society for a small grant to run your events. Also, a lot of universities have their own public engagement departments offering small pots of funding.

7. Reach out to organisations that can help you: If you are going to be working with school students then a great way to organise this is by becoming a STEM ambassador with STEM learning. They will do your DBS check for free and can help you to link up with schools in your area.

8. Entice people with freebies: You could hand out Society merchandise like our new sleep masks or leaflets with further info about your research. You could even have some kind of craft or food activity so that participants take their creation home.

9. Make it clear who you are and what you are about: A simple step is joining The Physiological Society and getting your very own I ❤ physiology T-shirt from us!

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10. Spread the word: Make sure you advertise your event as widely as possible. This of course depends on where it is being held. If it’s in the community you could try to promote it in newspapers or online. You could also make use of your university social media channels and get in touch with The Society.

The First Mars Marathon: Part 3

Martian nutrition: How runners will fuel

Carb-loading for the Red Planet marathon might prove more difficult than simply gorging on a pre-race pasta dinner. Since they will be shivering and burning a lot more calories not only during, but before the race, runners will simply have to eat more on Mars during the pre-race period to fully saturate their muscles with glycogen.

Just getting plates of pasta to Mars will be a major issue. After years in transit, many of the nutrients in any food shipped to Mars will have been lost, and deep-space radiation will have degraded much of a food’s chemical and physical structure. Preparing and shipping food to Mars for the runners to eat requires special methods. Anyone care for high-pressure processed, microwave sterilized, freeze-dried spaghetti and meatballs…anyone?

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Use of critical fuels such as carbohydrate and fat will drastically increase on mars due to the extreme cold

Mid-race nutrition is equally important. As stated earlier, the drastically cold temperatures will result in a higher rate of glucose use and glycogen depletion, so the runners will need to fuel more often to keep glucose stores elevated in the face of increased use of these from shivering, coupled with the metabolic demand of running. Marathoners, who rely heavily on their glycogen stores into the later miles of the race will need to ingest glucose during the race at a rate exponentially higher than the recommended 25-60 grams per hour to avoid hitting the dreaded wall around mile 20 of the Red Planet marathon. This drink will likely have to be specially formulated with a higher glucose content.

Authors of a 1998 paper in Experimental Physiology provide evidence that providing a drink containing 15% carbohydrate was able to maintain blood glucose levels better than one containing just 2% during a cycling test to exhaustion (1). For this reason, Martian aid stations will need to occur at regular intervals and provide runners with carbohydrate-rich gels, drinks, or tasty freeze-dried space snacks.

What they’ll wear

Until we evolve into actual Martians, humans won’t get away with running unprotected on the surface of Mars. For now, technology will prove vital to success as runners on this new planet. Newly minted Martian sports scientists and gear technologists will be recruited to design a top of the line marathon-specific spacesuit.

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Theoretical concept of the Mars runner suit. Source: News.mit.edu

This suit will provide a sealed, pressure-controlled environment, help maintain some warmth and control body temperature, riding a fine line between protection and optimal range of motion. A protective suit is necessary: in the low atmospheric pressure environment of Mars, bodily fluids would boil. This is known as the Armstrong limit of pressure, which Mars sits well below.

Additionally, runners will develop severe impairments in blood pressure maintenance due to the reduced atmospheric pressure. This drastic reduction in blood pressure was demonstrated in a Journal of Physiology study from 2015 (2). Studying astronauts on the International Space Station, researchers noted a reduction in blood pressure of 8-10 mmHg, mainly due to central volume expansion.  The marathon gear will resemble something of a wet suit– a design which is able to solve the low-pressure problem by using super tight wrapping  (instead of gas-pressurization, it uses mechanical counter-pressure) (3). This leaves the body mobile. Wrapping the lower limbs in this counter pressure “fabric” will allow full range of motion at the ankles, knees, and hips,

The suit will require an enclosed helmet with breathing apparatus for runners to get their oxygen which is lacking in the Martian environment and dispense of the large amount of atmospheric as well as metabolically produced CO2. But don’t even think about attempting a snot-rocket.

Additionally, features of the suit crucial to completing our space-race might include an airtight hole in the mask so that runners can ingest their mid-race fluids and gel packs.

One final, and perhaps most vital feature will be the shoes. Just as elite runners have custom shoes designed to their unique gait pattern and foot size, Mars marathoners will need footwear tailored with the same precision and comfort in mind. As it turns out, the painful condition of onycholysis (separation of the finger/toe nail from the nail bed) is not just a problem among ultra-endurance athletes, but astronauts too. Ill fitting gloves combined with the intra-suit pressure can spell disaster (and pain) for anyone carrying out activities in space, and this would surely apply to the feet as well. After 26 miles of running in cramped space-boots, it can only be expected that runners might lose one or more toenails. To prevent this, it will be necessary for runners to have Mars boots fit to their particular foot size, strike, and biomechanics.

Can They Do It?

Just as Opportunity Rover completed its own Red Planet marathon, so too will humans eventually cover 26.2 miles on foot over the dusty red surface of the fourth planet from the Sun.

Will it be fast? Probably not – but let’s hope we break the current standing record of 11 years, 2 months. Evolving a new, skipping gait required for efficient running on Mars will take some time, just as did the adaptation of lower limbs and body structure of Australopithecus to that of the modern Homo erectus, a body ideally formed for endurance running. Tendons and ligaments will have to adjust to the new microgravity environment, and it will take time for muscle fibers to regain their strength and capacity. The deconditioning of the cardiovascular system (due to fewer hemoglobin molecules, reduced ability to both supply and utilize oxygen, and decline in heart and lung function) will take some time to adapt to. Along with the various environmental factors (extreme cold, hypoxia, and dangerous levels of radiation), runners will certainly have a slow marathon debut.

We will eventually design equipment and training protocols that allow us to traverse 26.2 in record times on Mars. Remember, the first marathon run by Pheidippides resulted in his keeling over in death upon arrival. Since then, we have perfected running tactics, advanced our knowledge of performance, and unlocked human physiology such that it is now possible for man to run 26.2 miles at an astonishing 4 minutes and 41 seconds per mile, something once thought impossible.

Perhaps, some day, the elusive 2-hour barrier will be broken, not on a curated and well-paced course in Italy, but near Endeavor crater, some 54.6 million kilometers away.

References:

  1. Galloway et al. The effects of substrate and fluid provision on thermoregulatory, cardiorespiratory, and metabolic responses to prolonged exercise in a cold environment in man. Experimental Physiology. 81 (1998); 419-430
  2. Norsk et al. Fluid shifts, vasodilatation, and ambulatory blood pressure reduction during long duration spaceflight. The Journal of Physiology 593.3 (2015); 573-584
  3. Shrink-wrapping spacesuits. Jennifer Chu, MIT News Office. September 18, 2014. http://news.mit.edu/2014/second-skin-spacesuits-0918

 

The First Mars Marathon: Part 2

By Brady J. Holmer, @B_Holmer

Unlikely or not, it is interesting to ponder the physiological and technical challenges of a Martian marathon. Read our post from last week to learn why runners will be moving in giant leaps. Stride aside, how will the freezing cold, lack of oxygen, calorie requirements, and protective clothing affect the runners?

Cons of the Mars environment:

Temperature: beyond chilly

Race day conditions can be quite unpredictable even on Earth, and Mars will be no exception. Temperatures can vary from a moderate 70˚ F (20˚ C) around noon to an unbearable -195˚ F (125˚ C) at night. For the sake of this thought experiment, let’s assume that race day temperatures hover around the average of -67˚ F (-55˚ C).

At this temperature the blood vessels in many organs and leading to the skin will undergo profound constriction, reducing blood flow to areas where the runners don’t need it (that is, everything but the legs, brain, lungs, and heart). This conserves heat and maintains core body temperature as close to normal as possible.

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Average race day temperatures at select endurance races.

Authors of a classic 1998 paper in Experimental Physiology demonstrated that this constriction can occur even at a “mild” temperature of 45˚F (7˚C) for just 90 minutes (1).

Exaggeration of this physiological response in instances of extreme cold (i.e. Mars) would occur due to a condition called non-freezing cold injury (2). Symptoms include damage to vascular tissue and heightened constriction of blood vessels. This means runners will have trouble providing oxygen-rich blood to their working muscles which will be in competition with the core to maintain a survivable temperature. Frostbite on Mars sounds disproportionally painful.

Another main concern of extreme cold exposure will be the detrimental effects of shivering thermogenesis, the body’s involuntary quivering of muscles to produce heat in an attempt to maintain core body temperature. To do this, the body must use fuel sources such as carbohydrate and fat. This also occurs at even relatively “mild” cold temperatures.

A study appearing in a 2005 issue of The Journal of Physiology exposed a group of men to a temperature of 41˚F (5˚C) for just 90 minutes and showed that utilization of glucose and glycogen increased five-fold from normal resting conditions (3). Muscle glycogen, our stored form of carbohydrate, contributed up to 60% of the total increase in heat production during just moderate-level shivering.

Exposure to Mars level cold would exacerbate these effects in runners and lead to a sacrifice of valuable fuel stores in an attempt to stay warm, leaving little for the marathon effort. In a race over 2 hours such as the marathon, fuel partitioning is key, and glycogen stores become important late into the race. Without fuel to provide energy for muscle contractions, performance will inevitably suffer, even if proper nutrition and “carbo-loading” are implemented.

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Solar particle events will lead to a destruction of valuable red blood cells in space.

Oxygen deprivation in the air

Given the vast difference in the composition of the air, breathing on Mars will also be difficult.  The atmosphere of Mars is 95% carbon dioxide (CO2), meaning there is very little oxygen. Normally, CO2 is produced during high intensity exercise such as marathon running, but is counteracted by expiration, preventing accumulation of acidifying ions and the ensuing unpleasant burning feeling in the lungs and legs. In this regard, Mar’s atmospheric gas composition presents an ideal situation for the lung-torching turmoil that all runners fear late into the end miles of a marathon, although now, this will occur from the start. Even the most rigorous altitude training regimen won’t prepare Martian runners for the low-oxygen conditions they will experience. Well-designed spacesuits will need to be implemented to allow runners to inhale a gas composition that resembles one on Earth, while simultaneously helping to expire CO2 at a higher rate than usual.

Wreaking havoc with red blood cells

Let’s not forget about the radiation. Mars’ atmosphere is less dense than the Earth (approximately 100-fold less so), and radiation from the sun is much more potent. Spontaneous and largely unpredictable solar flares that decide to pop up during the marathon will send charged helium nuclei, neutrons, protons, and other dangerous and highly energetic particles coursing through the runner’s bodies. Exposure to one of these solar particle events during the Mars marathon would lead to the destruction of red blood cells (hemolysis) and along with it, the all-important, oxygen carrying hemoglobin molecules, oxidative stress, and damage to muscle fibers.

Runners will likely fall victim to a condition we might call “space anemia”. A study in Physiological Reports from 2017 investigated the response of the circulation to a head down tilt bed rest condition – used to simulate microgravity encountered in space – and found that it resulted in a loss of hemoglobin  (4)! Hemoglobin is necessary to carry oxygen to sites of active muscle during running, and a reduction  is associated with a lower exercise capacity.

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Aerobic capacity and power will both decline after just 15 days in space.

Reduced circulation

Circulatory changes may be further exacerbated by the well-known detrimental effects that microgravity has on aerobic capacity. Indeed, researchers have used a model of sustained bed rest further compounded by low-oxygen space environments such as Mars, to investigate the effects on cardiovascular capacity.

Keramidas et al. demonstrated in a 2017 Experimental Physiology paper that just 10 days in this space-simulating condition impaired whole-body peak oxygen uptake (VO2peak) by 8% with an accompanying reduction in peak power output during an exercise test (5).

Furthermore, in 2018, Salvadego et al demonstrated in The Journal of Physiology that 21 days of hypoxic bed rest led to an 8% reduction in V02peak, a reduction in thigh muscle volume, and impairments in the body’s production of energy (mitochondrial respiration and aerobic metabolism) and an ability to match oxygen supply to demand during leg exercise (6).

These changes lead to a reduction in aerobic performance – and Mars runners will fight against all of these pathological changes as they try and complete the race as they find themselves starved of the ability to get crucial, oxygen rich blood to their working muscles during the race. This means that runners will be less capable of performing at their max capacity on race day.

So far, the prospects are looking quite grim for the runners. Will nutrition or protective suits be their saving grace? Find out on Friday in the final blog of our series.

References

  1. Weller et al. Physiological responses to moderate cold stress in man and the influence of prior prolonged exhaustive exercise. Experimental Physiology. 83 (1998); 679-695
  2. Tipton M.J. Environmental extremes: origins, consequences, and amelioration in humans. Experimental Physiology 101.1 (2016); 1-4
  3. Haman et al. Partitioning oxidative fuels during cold exposure in humans: muscle glycogen becomes dominant as shivering intensifies. The Journal of Physiology 566.1 (2005); 247-256
  4. Trudel et al. Hemolysis during and after 21 days of head-down-tilt bed rest. Physiological Reports. 5.24 (2017)
  5. Keramidas et al. LunHab: interactive effects of a 10-day sustained exposure to hypoxia and bedrest on aerobic exercise capacity in male lowlanders. Experimental Physiology 102.6 (2017); 694-710
  6. Salvadego et al. PlanHab: hypoxia does not worsen the impairment of skeletal muscle oxidative function induced by bed rest alone. The Journal of Physiology 000.00 (2018); 1-15