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Welcome to the HPRC Blog. We've got lots of information here, from quick tips to in-depth posts about detailed human performance optimization topics.

HPRC Fitness Arena: Environment

Aviation and hypoxia

HPRC Fitness Arena: Environment, Total Force Fitness
Filed under: Aviation, Flight, Hypoxia
Hypoxia in aviation is a real threat. Learn the signs and symptoms to recognize it.

Hypoxia, or insufficient oxygen supply to the body, is a stress factor associated with high altitude in aviation. It’s caused by low oxygen levels and decreases in partial pressure. Flight above 10,000 feet is dangerous and restricted without supplemental oxygen, and even the best oxygen and pressurization systems fail sometimes. Above 10,000 feet, an aviator’s “Time of Useful Consciousness” (TUC) begins; this means that you’re going to start having problems focusing, reacting, and making decisions. At 15,000 feet your TUC is around 30 minutes, at which point you’re more likely to be unconscious than not. At 22,000 feet it’s only 5–10 minutes, and by 28,000 feet it can be as fast as 3 minutes! Look out for these signs (what you can see in somebody else) and symptoms (what you can notice in your own body):

  • Cyanosis (bluing of the fingertips or lips)
  • Headache
  • Decreased reaction time
  • Impaired judgment
  • Unexplained happiness/euphoria
  • Visual impairment
  • Drowsiness
  • Lightheaded or dizzy sensation
  • Tingling in fingers and toes
  • Numbness

If you notice any of these signs or symptoms, remember to find the emergency oxygen, use it, and land safely!

Decompression sickness

HPRC Fitness Arena: Environment
Decompression sickness can happen at altitude with loss of pressure. Know the symptoms.

Decompression sickness (DCS), also known as “the bends,” is well known to occur in divers. However, it also can occur in aviation, especially when there is a sudden or unexpected loss of cabin pressure above 18,000 feet. DCS occurs when the dissolved gases inside the body come out of solution to form bubbles. As these bubbles move throughout the body, problems occur. There are different types of DCS, but here are some common symptoms to be aware of:

  • Localized or deep pain in the large joints
  • Itching or the sensation of insects crawling on your skin
  • Tingling
  • Numbness
  • Confusion
  • Memory loss
  • Dizziness
  • Visual abnormalities
  • Headache
  • Fatigue
  • Loss of balance or vertigo
  • Dry, persistent cough

If you suspect DCS, first land safely as soon as you can. Treatment may involve breathing oxygen or time in a hyperbaric chamber. If you ever experience these symptoms after a loss of pressurization above 18,000 feet, contact your doctor or emergency room as soon as possible and report your recent exposure.

The foundations of Total Force Fitness

Get back to basics with the foundations of Total Force Fitness: health, resilience, and performance optimization. What are they and how do they go together?

Have you heard the terms “resilience” and “Total Force Fitness,” but you’re not quite sure what they mean or where they fit into the health and performance picture? Read on.

Your health is the foundation. The 2010 article "Why Total Force Fitness?" states, “nothing works without health.” Health is not just physical and not just something to worry about when you’re sick. Health is a combination of physical, mental, spiritual, and social well-being and includes practices that promote wellness in addition to those that help you recover from sickness or injury.

Resilience is next. Resilience is the ability to bounce back—or even better, forward—and thrive after experiencing hardship. It is not the ability to completely withstand hardship but rather the ability to come back from it and grow stronger through the experience.

Next is human performance optimization (HPO). Unlike resilience, which typically requires the experience of hardship, HPO involves performing at your best for whatever goal or mission you have (whether that is your PT test, a combat mission, or raising children). It goes beyond simply resisting challenges; it means functioning at a new optimal level to face new challenges.

Health, resilience, and optimal performance are the foundations of Total Force Fitness, which is defined in the “Physical Fitness” chapter of “Total Force Fitness for the 21st Century” (see link above) as a “state in which the individual, family, and organization can sustain optimal well-being and performance under all conditions.” Being totally fit requires a holistic approach—that is, an approach that doesn’t focus on just one aspect alone such as nutrition or physical fitness, but on multiple domains of fitness. It means attending to your mind (including psychological, behavioral, spiritual, and social components) and your body (including physical, nutritional, medical and environmental components). In order to achieve Total Force Fitness, these factors come together to enhance your resilience and/or performance.

This is where HPRC can help you on your quest for total fitness. By visiting each of our domains—Physical Fitness, Environments, Nutrition, Dietary Supplements, Family & Relationships, and Mind Tactics—you can get evidence-based information on a variety of holistic topics to help you achieve and sustain total fitness. But remember that total fitness is a life-long process that will ebb and flow. And it isn’t just about you; your loved ones are an important piece of the picture, too.

To learn more, check out HPRC’s "What is 'Total Force Fitness'?" and for in-depth information, visit the Total Force Fitness Articles section of HPRC’s website.

Remembering on Memorial Day

Filed under: Memorial Day
Memorial Day is not only a time to remember those who have served but to remember how to serve those who do.

Today is Memorial Day. Memorial Day began as “Decoration Day” after the Civil War. In 1882, Decoration Day became widely known as Memorial Day, and after WWII it became a day to remember all our fallen heroes, not just those from the Civil War. In 1967, Congress passed the law making it an official holiday to be celebrated on May 30, subsequently changed to the last Monday of May. We at HPRC extend our greatest appreciation to those who have perished for our nation and offer our sincere sympathy for the families left behind. There are many ways people choose to remember those who gave their lives as a supreme sacrifice to our country and its ideals. HPRC is dedicated to providing our Warfighters and their families the information they need to build resilience to prevent injury and illness and carry out their missions as safely and effectively as possible. Our desire is to reduce the level of sacrifice our warriors have to make as they fulfill their future missions for us and for our nation.

Too loud for you to hear?

There are some tips you can use to prevent exposure to hazardous noise levels recreationally and occupationally.

A staggering number of Americans (approximately 36 million) have hearing loss, and one-third of those probably could have been prevented. Hearing loss continues to be a safety hazard for Warfighters at home and in the field. So how do we combat this not-so-silent epidemic?  Here are a few tips to help you protect your hearing.

  • Wear a hearing protective device (HPD). HPDs should be worn for noise levels at or above 85dB. Not sure what 85dB really means? Check out this guide to occupational noise levels.  Also check out “How Loud is Too Loud?,” a graphic designed to inform Warfighters about how and when to choose the proper HPD for their jobs.
  • Learn how to wear your HPD correctly. Even if you have the correct protection, it may not be effective if you’re not wearing it correctly.
  • Always have disposable HPDs handy. Disposable HPDs are lightweight and easily portable. Make them a part of your everyday gear.

For more information about how to protect yourself against or to seek help for hearing loss check out the DoD Hearing Center of Excellence website or make an appointment with your local hearing loss treatment center.

Computer Vision Syndrome

Learn how to recognize and prevent eye problems associated with extended computer monitor use.

As you read this article right now, your eyes are working harder than they would if you were reading a book or even watching TV. Attention, desk warriors! If you stare at a computer for most of the day, you could leave work experiencing dry eyes, headaches, and blurred vision. 90% of people who work on a computer experience symptoms of Computer Vision Syndrome, or CVS. Symptoms include blurred vision, dry eyes, headaches, eye strain, irritation, redness, and any number of other ocular symptoms.

Computers have become a necessity in our world, so monitors are here to stay. Here are some of the causes of CVS and some tips to help you protect your eyes from the screen:

  • Blinking. One of the main symptoms of CVS is eye dryness. This occurs for two reasons: First, your eyes are focusing on the same depth of field for an extended period of time; second, unlike the non-stop action on a TV screen, there may be little movement happening on your computer screen. The lack of movement and constant field depth leads to less blinking and, therefore, eye dryness.
    Fix it
    by spending 30 seconds every hour or so adjusting your eyes to something far away. If you work in a small office, put up a picture and focus on something small in the background. This change in depth of field will exercise your eyes, and you’ll blink more!
  • Monitors. The pixels on a computer screen can cause some problems. Because they are not all the same brightness, they don’t produce the same contrast. And they can cause words or pictures on the screen to look fuzzy, straining your eyes and contributing to CVS.
    Fix it
    by investing in a good LCD monitor if you have not done so already. LCD monitors reduce glare and contrast, as compared with older types of monitors. If you already have an LCD monitor, then talk to an ophthalmologist about getting some reading glasses to help reduce eye strain. Adjusting the lighting in the room and/or on your computer screen can also help soften the symptoms of CVS.
  • Existing vision problems. You may already have a vision problem that went undiagnosed until you started staring at a computer. Extended computer use can exaggerate already existing eye conditions and lead to some of the symptoms of CVS.
    Fix it
    by talking to a physician about corrective lenses. The Vision Center of Excellence has excellent resources from the VA and DoD for vision support.

In summary: Protect your eyes from CVS by taking frequent breaks from the computer, by blinking more often, and by making sure you work in an ergonomically efficient office setup. If you want to more information about CVS, check out “A Survival Guide to Computer Workstations.”

Spring forward, but don't miss out on sleep!

HPRC Fitness Arena: Environment, Mind Tactics
Don’t lose sleep when you spring forward. Get ready to change to Daylight Saving Time.

Remember to adjust your clocks one hour ahead on Sunday, March 9, to switch to Daylight Saving Time (DST). Sleep is important to your overall performance; losing just one hour can affect it. You don’t have to feel that loss if you prepare to spring forward:

  • Adjust your bedtime. This can help you accommodate losing an hour of sleep. For example, if your bedtime is 10 p.m., try going to sleep earlier the week before so that you can handle the time change when it arrives. You can do this gradually by adjusting your bedtime in 15-minute increments each day leading up to the time change.
  • Take a nap. Naps can help make up for sleep debt. If you are not fully adjusted when Sunday arrives, remember that it’s okay to use naps to adapt to your new schedule.
  • Re-set your sleep habits. If you’ve thought about improving the quality of your sleep, this may be a great time to re-set your sleeping habits.
  • Check DST observances. If you are travelling or deployed, remember to check if the state or country you’re in observes DST or if they do so on a different day. Arizona, Hawaii, and some other U.S. territories do not.

Maintain optimal performance and make the transition smoother with these tips. For more information on sleep and performance, visit our Sleep Optimization page.

“Winter is coming...”

HPRC Fitness Arena: Environment, Total Force Fitness
Filed under: Cold, Environment, Winter
Well, winter may actually already be here, depending where you are, so make sure you’re prepared in case of a winter weather emergency.

Winter’s not over yet. The next month or more can bring anything from ice and sleet to “Snowmageddons” and polar vortexes. Winter weather can be dangerous for you, your family, and even your pets if you’re not prepared. In the event of an emergency you should know what to do to protect yourself and your loved ones. The National Center for Disaster Medicine and Public Health has compiled a list of resources that offer information, tips, and checklists for winter-weather emergencies and general cold-weather health. Stay warm, safe, and resilient!

Assistive technology for total fitness

Returning injured service members to their highest level of function sometimes requires the use of “assistive technology.” Read about the many options available to today’s Warfighters.

For some injured Warfighters, achieving total fitness may include assistive technology (AT). Assistive technology is any physical equipment or system used to improve or help maintain the functional abilities of an individual. There are assistive technologies for almost every disability or injury, such as communication boards, both manual and electronic; technology for vision and hearing impairments (magnifiers, talking watches, hearing aids); tools to assist daily tasks (shower chair, adapted eating utensils); adaptive sports equipment (sit-skis, sport wheelchairs, recumbent tricycles); and technologies that enable mobility (from a cane or walker to sophisticated prosthetic legs and powered wheelchairs). Driving aids and fully equipped vans are other important assistive mobile technologies. Mobile assistive technology can promote independence and increased quality of life. Even phones and apps can be used as memory aids and organization- and time-management tools for helping with traumatic brain injury and psychological health. If you’re an injured Warfighter looking at the possibility of AT (or if you just want to know more), there are many things to consider when choosing the right AT for you, including:

  • First and foremost, understand your own goals, priorities, and preferences and discuss them with your healthcare team. A person’s reaction to AT is both personal and complex. You must be closely involved in the choice of your assistive technology to ensure a “good match.”
  • Consider where you will be using your assistive technology (indoors or outdoors).
  • Consider how you will feel about using your equipment. AT equipment shouldn’t be embarrassing, inconvenient, or cumbersome.
  • Have you accepted your challenge, and are you ready to move forward? Finding a "new normal" to accomplish your goals may include using assistive technology, but you must first embrace this concept.

For those who can benefit, AT can be a big piece of Human Performance Optimization (HPO), part of HPRC’s Total Force Fitness mission.

Running indoors versus outdoors—does it matter?

Have you ever wondered whether it’s better to run on a treadmill or outdoors? You’re not alone. Read on to learn the answer.

Training on a treadmill versus running outside – is there a difference, besides the scenery? Is one better than the other? These are frequently asked questions in the running world, especially when the weather makes outdoor running a challenge. Researchers provide a short answer: Training on the treadmill and “overground” running are not the same.

If you’ve experienced treadmill running and find yourself more tired afterwards than you would on an outdoor run, you’re not alone. Studies have found that athletes actually run slower on a treadmill than their normal pace outside, although they perceive treadmill running as being more exhausting. In other words, even though it feels more difficult, treadmill running is usually less intense and less physically challenging than running outdoors.

However, running indoors can be helpful if you’re recovering from an injury since running on a treadmill is easier on your joints than running outside on concrete or even grass.

Bottom line up front, you do run differently on a treadmill than you do outside, even if you don’t realize it. If you’re training for an outdoor race, ideally you should run most of your training miles outside. When you want to or need to run indoors on a treadmill, set the incline at 1–2% to increase your exertion level to more closely replicate your outdoor runs.

If you do decide to run outside during a cold spell, take a look at our article with tips for staying safe and the many resources where you can find more ways to keep warm and hydrated even in frigid weather. Remember: Whether you stay in or venture out, any exercise is better than none!

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