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
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.”
Before 2013 comes to a close, the Navy will begin distributing Flame Resistant Variant (FRV) coveralls to all Sailors assigned to surface ships and aircraft carriers. Previously, only Sailors working in engineering departments, on flight decks, and in other high-risk areas were issued flame-resistant clothing. However, a recent review found that the highest risk of severe injury from flames was from major fires or explosions, which puts any Sailor at risk. Tests revealed that the Navy Working Uniforms (NWU) type I, made of a polyester cotton blend, are susceptible to melting in a fire, which could cause even greater injury to the wearer. The new FRV coveralls are 100% cotton with a fire-resistant coating, which is self-extinguishing. The Navy plans to improve and standardize all coveralls over the next couple years by combining the protective effects of flame resistance, arc-flash protection, and low-lint specifications into one safe and effective uniform.
Veterans who served in the U.S. and abroad between September 2001 and March 2010 were four times more likely than civilians to suffer from severe hearing loss. In fact, two of the most common disabilities affecting service members today are hearing loss and tinnitus, says the Hearing Center of Excellence (HCoE). Hearing loss and tinnitus seriously impact force readiness as well as the emotional and social well-being of those affected.
However, not all hearing loss results from the noise pollution Warfighters experience in the field. Many everyday exposures, such as your MP3 player or loud music in your car, can be just as damaging as firearms or helicopters. To maintain good hearing and operational readiness, Warfighters must use safe listening practices at all times. HCoE recommends these safe listening practices:
- Never listen to your MP3 player at maximum volume.
- Following the “60:60” rule: 60 percent maximum volume on your MP3 player for no more than 60 minutes a day.
- Take periodic breaks of 15–20 minutes when listening to loud music to allow your ears to recover.
- Select headphones or earbuds designed to remove background noise.
- Exercise caution when listening to music in the car. Listening in a confined space increases the risk of hearing damage.
- Wear hearing-protection devices such as earplugs at concerts, sporting events, parades, and other high-noise situations.
For more information on how to protect your hearing, as well as treatment and rehabilitation for hearing loss, please read this article from HPRC and visit HCoE.
You’ve heard of “Army Strong?” As part of the Ready and Resilient campaign, the Army is rolling out its new Performance Triad as a “pathway to a fit and healthy force.” The triad consists of sleep, physical activity, and nutrition and provides online tools and information such as the Performance Triad Training Sessions (videos and websites packed with details to help you do everything from preventing injuries to choosing dietary supplements), cards with practical tips to become healthier and stronger, and a whole lot more. The Soldier's Guide is a good place to start; it includes numerous links to HPRC and other sources of information. Go ahead and start optimizing your health and performance today!
For more information on integrative practices and programs, check out HPRC’s Total Force Fitness domain.
Getting an extra hour of sleep is a dream come true for many of us. For others, the end of Daylight Savings Time means an extra hour on the town or time to catch up on a to-do list. No matter how you choose to spend your extra hour, the amount of sunlight typically decreases over the following weeks, depending on where you are in the world. The change in daylight may influence your outdoors activities, so take this time to make a plan for how to remain active in the upcoming “dark days” of Standard Time.
Plan ahead for outdoor activities in the dark:
- If you jog or hike outdoors in the morning or evening hours, wear reflective or light-colored clothing to be easily visible.
- Plan your route ahead of time and let someone know when and where you will be exercising.
- Have a cell phone handy in case of emergencies.
- Be vigilant. A head-mounted flashlight can help you see holes and debris in your path to avoid sprains and injuries. Also beware of animals that might spook as you pass them in the dark.
- If you must wear earphones, only use one ear bud.
- Bring a buddy or pet!
Plan fun activities indoors:
- Move your exercise routine indoors. Whether in the gym or at home, there are plenty of ways to stay active. Try High Intensity Tactical Training (HITT) for a vigorous workout. Or take this time to give yoga a try or deepen your practice.
- Plan activities that get the entire family involved. Even if you don’t have a gaming console, you can try dancing, hula hoop, or a jump-rope contest. HPRC has more family fitness ideas you can try.
- Finally, think about how much sleep you usually get. Do you get the recommended seven to eight hours every night? This extra hour might be the jumpstart you need to begin prioritizing sleep. For more information on sleep tips, check out HPRC’s Sleep Optimization section.
Compression garments are becoming more and more popular in the sports world. Back in 2001, NBA All-Star Allen Iverson began wearing a sleeve on his arm to help with bursitis in his elbow, helping to increase blood circulation and reduce swelling in his arm. Similar sleeves are used for clinical conditions such as lymphedema, where blood circulation is poor, or to prevent blood clots.
You can find compression garments as sleeves, socks, shorts, or even full-body suits. There are various levels of compression for garments, but they all have gradient pressure, which means they’re a little tighter at the bottom of the garment and a little looser at the top to help push blood toward your heart and prevent blood from ‘pooling’ or remaining in the compressed areas. Most garments need simple measurements around your arms or legs to make sure you have the correct size.
But can these garments also impact your performance and recovery? It’s been found that compression garments do actually help with blood flow and increase oxygen to working muscles. But whether that translates into improved performance is another question altogether.
Most performance-related studies have looked at the effects of compression sleeves or socks on running. Some participants said they didn’t feel they were working as hard when wearing compression garments on their legs. While the relationship between compression garments and performance is still not clear, some researchers have suggested that this psychological benefit of lower perceived exertion might help athletes train at higher intensity. However, more research is needed to show if this ultimately leads to actual performance improvements.
In terms of recovery, more research is needed too. The effects of compression garments on muscle soreness after exercise have been mixed, but there have been no studies on the use of compression socks or sleeves for shin splints and other leg pain. They are sometimes effective at reducing the muscle soreness that occurs 24-48 hours after exercise. Relief of symptoms from wearing these garments varies from person to person, sometimes with no benefit. And it isn’t clear whether wearing these garments during recovery will improve your performance next time.
The Human Performance Resource Center is here to serve Warfighters and their families, commanders, and healthcare providers. If you’ve visited before, you probably know that we focus on “total force fitness.” But do you really know what that means—or how HPRC got started? If you’re curious, check out this PDF that describes HPRC, what we do, and the vast amount of information we cover. In addition, you may have noticed that we use the term “human performance optimization” throughout our site; this article also explains what that means.
Prosthetic limbs have come a long way in a short amount of time, mostly because of the number of service members coming back from deployments with traumatic injuries and with the demand for better technology. Advancements in prosthetic arms now include devices that can move and bend individual fingers and joints. However, a sense of touch is one remaining obstacle—but one that researchers are close to conquering.
Many patients with arm prosthetics describe the difficulty with grabbing objects because there is no feedback to the brain. For example, breaking dishes, bruising fruit by grabbing it too hard, and dropping slippery cans are all too likely without any sense of feeling in the hand.
Researchers are now developing a prosthetic limb—called the Modular Prosthetic Limb—that will close the loop between the brain and the prosthetic hand by adding various sensors to contact points such as the fingertips and joints. This will allow sensory feedback to the brain that gives the user enough “feeling” to distinguish between a wool sweater and a cold beverage, for example.
The Department of Defense is working with various universities such as Johns Hopkins and the University of Pittsburgh to develop this unique device and make it available to wounded warriors.
Walk into any fitness center on base or take note of a group of soldiers training, and you’ll probably notice at least a few people in form-fitting synthetic t-shirts. The sports apparel industry has exploded in popularity over the past decade, with numerous manufacturers now competing to develop, market, and sell the newest pieces of clothing (shirts, shorts, underwear, socks), all geared to keep athletes cool while competing or training in hot environments. Is there any science behind these claims? Does tight-fitting clothing made of “high-tech” materials actually help with heat regulation and enhance athletic performance?
You heat up when you exercise, and sweating is the primary method your body uses to stay cool. Sweat evaporating off your skin is the most important method your body has to cool itself during exercise. High-tech materials are supposed to enhance “wicking”—the delivery of sweat away from the skin surface toward the clothing, which allows for evaporation—and limit the absorption of sweat by the clothing itself. Cotton, by contrast, absorbs moisture, so it’s not considered a good choice for exercise.
To date, there’s no evidence that this high-tech clothing improves thermoregulation when worn during exercise in hot environments. Specifically, researchers found no differences in heart rate or body and skin temperatures when subjects performed repeated 20–30 minute bouts of running outfitted in shorts, sneakers, and either a form-fitting compression or traditional cotton t-shirt. Research has also found that wicking sportswear had no effect on cooling when worn under a bulletproof vest or on a cycling sprint when worn under full ice hockey protective equipment. As of now, the best advice for staying cool during exercise in the heat is to wear lightweight clothing, stay properly hydrated, and listen to your body for signs of potential heat illness. For more information on performing in hot environments, please visit the “Heat” section of HPRC’s Environment domain.
Performing physical activity—whether exercise or mission demands—at moderate (4,000–7,900 ft or 1,200–2,400 m) and high (7,900–13,000 ft or 2,400–4,000 m) altitudes can be challenging. At high altitude, oxygen pressure is lower, which results in less oxygen in the blood and muscle tissues. And as altitude increases, there’s a decrease in air temperature (about 2°F for every 500 ft or 150 m), less moisture (resulting in drier air), and increased solar radiation. Use sunscreen, drink plenty of water, and watch out for the signs of acute mountain sickness: headache, nausea, shortness of breath, and impaired cognition and balance.
To learn more about altitude sickness, read the article “The Invisible Enemy of the Afghanistan Mountains” on the United States Army Research Institute of Environmental Medicine (USARIEM) website. And learn more about performance at altitude in the Altitude section of HPRC's Environment domain.