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
Face paint has been used for many decades to blend the appearance of Warfighters’ exposed skin into their environments and protect them from the enemy. The American Chemical Society is taking a new approach to the traditional camouflage face paint by making it from a material that also can provide some protection from the heat wave of roadside bombs, IEDs, and other explosions on the battlefield. Thermal blasts last only a few seconds, but can cook the face, hands, and other exposed skin. The new face paint will protect exposed skin against temperatures reaching around 600 degrees Fahrenheit, for up to 60 seconds. The paint even incorporates the insect repellent DEET in a form that will not catch fire.
This new face paint is still in the testing stages, but already there are plans for a colorless form for use by men and women in other occupations—such as firefighters and other emergency responders—who are at risk of extreme heat exposure.
Heat illness is a hot topic for the military. Did you know there is a spectrum of conditions that fall under the term “heat illness,” some more severe than others? HPRC has great resources on how to prepare for exposure to hot environments and how to prevent heat illness. Read HPRC’s Answer to “What IS heat illness?” for more about what heat illness is and how to identify the signs that you might be developing more serious conditions.
On September 11, join an online webinar, Can You Hear Me? An Introduction to Hearing Loss Prevention, sponsored by the CDC, to discuss the primary causes of hearing loss, and learn how to prevent it. This educational event is free; however, there are a limited number of open lines, so log in early.
Although the military does not allow women to take part in direct combat, they routinely face the dangers of war. The Pentagon was recently pressed to develop better-fitting body armor for female soldiers, recognizing that men and women have different body shapes. Women have more curves, shorter torsos, and narrower shoulders than most of their male counterparts. The current male-based body armor creates gaps and additional pressure points that leaves service women vulnerable and reduces their performance (aiming a weapon, entering and exiting vehicles, etc).
Engineers are looking to create plates that conform to the female body, similar to the armor worn by TV’s popular Xena: Warrior Princess. There are some concerns regarding weight and protection, but so far the Army has tested eight sizes, with positive feedback from women Warfighters.
In 2004, the U.S. Army digitized its former camouflage pattern on standard issue uniforms. It was termed “Universal Camouflage Pattern,” or UCP, with the hope that it would serve as a one-print-fits-all for any environment. The theory behind the digital print was not the result of a fashion craze; it started in the late 1970s with two psychology professors at West Point. Neuroscientists divided the human visual system into two parallel circuits. One circuit told us where objects were located, the other what objects were. Officially called the “Dual Texture Gradient,” the idea was that the pixelated pattern would interfere with those circuits and make it difficult to identify objects. More research, based on how our brains processed MRI scans as boxes and rectangles, led camouflage experts to similar conclusions, that this pattern was smart camo. Initially, the Marines adopted the pattern from the Canadians. However, the pattern failed early trials in the U.S. Army, and troops reported that it performed poorly in combat.
In 2009, after a camo detection study, the Army revised the design for ground troops in Afghanistan to the current “MultiCam” pattern as a temporary solution. Currently, four designs from non-government vendors are in a bid to become the next camo pattern. Submissions required that designs include a woodland variant, a desert variant, and a transitional variant for every environment in between. The goal of extensive field tests will be to optimize performance range from 35-400 meters in a woodland environment and 35-500 meters in a transitional and desert environment. Testing of the first pattern, which resembles reptile skin, began in June. Testing of the other patterns could last up to nine months, and production of the new uniforms could begin as early as 2013.
More than two million new cases of skin cancer are diagnosed each year, and the number is growing. Skin cancer is a major public health issue, and with proper precautions you can decrease your risk considerably. Hopefully this information on sun safety will help you, whether you are a Warfighter or dependent, stay safe during all outdoor activities!
Ultraviolet radiation (UVR) has been identified as the most important risk factor for both melanoma and non-melanoma skin cancer. Exposure to UVR weakens the skin’s elasticity and can result in sagging cheeks, deeper facial wrinkles, skin discoloration, burn, skin aging, photosensitivity, and cancer. Taking steps to safeguard yourself is crucial, especially when participating in outdoor activities or exercising.
Sweating increases the skin’s sensitivity to the sun’s rays, magnifying the risk of sunburn and skin damage. Athletes who practice outdoor sports have been found to be at increased risk for skin cancer. Remember—the weather does not have to be sunny and hot for you to get sun damage. Ultraviolet rays penetrate clouds, exposing you to 80% of the UVR. Even skiers and mountain climbers are at risk for sun exposure and skin cancer because of the stronger UVR at altitude.
Follow these precautions from the Occupational Safety and Health Administration (OSHA) whether training for the PRT, patrolling, road marching, or participating in a summer league softball game:
Avoid burning. Avoid sun tanning. Also, try to avoid sun exposure during midday (11 a.m. to 3 p.m.) when the rays are the strongest.
Seek shade. When possible, especially during midday, seek shade under a tree or tent.
Cover up. Wear protective clothing, including hats, long-sleeved shirts, and pants when going outdoors. Keep in mind protection decreases when clothes are wet.
Use extra caution near water, snow, and sand. Ultraviolet rays can reflect off of these surfaces, which can increase your chance of sun exposure and skin damage.
Apply sunscreen. Use water-resistant sunscreen and apply 15-30 minutes prior to sun exposure to allow for it to absorb. Also, reapply after swimming, sweating, or toweling off. Be sure to take a look at the new FDA regulations regarding sunscreens and their effectiveness.
Wear sunglasses. Protect your eyes when working, driving, participating in sports, taking a walk, or running an errand. Solar ultraviolet B radiation can cause an increased risk of cataracts and cancer of the skin around the eye without proper cover.
It’s always important to remember hydration when engaging in outdoor activities as well! HPRC has useful tips on hydration and the consumption of sports drinks and caffeine during exercise in the heat.
Our bodies know when to sleep thanks to “circadian rhythms,” which are regulated by our brains on a 24-hour cycle. Circadian rhythms are linked to core body temperature, so ideally you should always sleep between 0300 and 0500, when your core body temperature is lowest and your performance abilities are at their lowest. Keep in mind that your individual circadian schedule is based on where you are and takes cue from environmental factors such as the sun and from social patterns. When crossing time zones, your internal clock needs time to adjust, which can take several days. Factors that influence this adaptation are:
- how many time zones are crossed, and
- whether you fly eastward or westward—the former takes longer to adjust.
Keep in mind that, in order to make up sleep or to adjust to a new zone, the best times to sleep are between 0300-0500 or 1300-1500.
For tips on how to improve your quality or length of sleep check out HPRC’s Sleep Optimization section, and for information on how sleep loss impacts all of the areas of Total Fitness check out HPRC’s Overview on sleep loss.
It’s always a good idea to replace old sunscreen, but next summer you’ll have even more reason to do so. Sunscreen companies have until December 2012 to revise their labels to abide by FDA’s new guidelines. The new labels will prevent manufacturers from false advertising with respect to the level of protection they provide. Sunscreens also will have to go through FDA’s testing to determine their effectiveness.
The new guidelines are summarized below:
Broad-spectrum designation: Sunscreens will have to pass FDA’s broad-spectrum test to be labeled as such. This confirms the sunscreen protects against both ultraviolet A and B rays, both of which contribute to skin cancer and early skin aging.
Use claim: Only broad-spectrum sunscreens with an SPF of 15 or higher can claim to reduce skin cancer risk and early skin aging if used as directed. Sunscreens with SPFs between 2 and 14 can claim only to help prevent sunburn.
Waterproof, sweatproof, and sunblock claims: Sunscreens will no longer be able to claim they are waterproof, sweat-proof, or “sunblock,” since those claims over-exaggerate their effectiveness. No sunscreen is waterproof or sweat-proof without the proper reapplication. Also, sunscreens do not “block” the sun; they reduce the penetration of the ultraviolet rays.
Water-resistance claims: Any sunscreen with a “water-resistant” label must indicate whether it is effective for 40 or 80 minutes while swimming or sweating.
Drug facts: All sunscreens must include standard drug-facts information on the label.
With the summer weather here to stay for a few months, HPRC wants to remind you of the dangers of heat illness and the importance of staying hydrated. This information can relate to any outdoor activity such as exercising, hiking, bike riding, or playing in the park.
HPRC has tips on preventing heat-related illness and various guidelines for avoiding heat injuries. Hydration is an important factor for keeping you and your loved ones happy and healthy. Children need to be careful as well since they seem to have an infinite amount of energy while playing outside. In addition to water, sports drinks can also be beneficial. Keep this information in mind while you are out and about with your friends, family, and pets. Happy Summer!
Inhalation of major air pollutants has been found to decrease lung function and exacerbate symptoms of exercise-induced bronchospasms, including coughing, wheezing, and shortness of breath. In order to meet oxygen demands during light- to moderate-intensity exercise, you take in more air with each breath. And when you breathe through your mouth, you bypass the nose’s natural filtration of large particles and soluble vapors. As your exercise intensity increases, you breathe faster and deeper, which also increases the amount of pollution inhaled and the depth it travels into your respiratory system.
If you live in or near a busy city, you are exposed to even more combustion-related pollutants—such as nitrogen oxides (NOx), carbon monoxide (CO), particulate matter (PM), and ozone—that can inflame your airways and worsen asthmatic responses. Exposure to freshly generated emissions is most common near areas of high vehicular traffic.
While indoor exercise is often a good alternative to limit exposure to outdoor pollutants, some indoor conditions may be just as toxic. Nitrogen dioxide (NO2)—the more toxic NOx—is usually higher in gas-heated homes and indoor areas with poor ventilation. Carbon monoxide poisoning is also more likely to occur indoors. When carbon monoxide is in your system, the blood carries substantially less oxygen, reducing performance and eventually leading to carbon monoxide poisoning. Be sure to choose well-ventilated areas for indoor exercise.
Particulate matter and ozone are two significant pollutants you may be exposed to outdoors. Inhalation of high levels of particulates has been shown to reduce exercise performance as much as 24.4% during short-term, high-intensity cycling. Women may be more vulnerable than men to certain particulates, associated with greater decrements in performance. Ultrafine particle concentrations are highest in freshly generated automobile exhaust, and these small particles can be carried deep into the lungs. However, the further away you are from fresh exhaust, the less concentrated the particulates.
Bad ozone occurs lower in the atmosphere; it is not directly emitted into the air but is created from chemical reactions between NOx, volatile organic compounds (VOCs), heat, and sunlight. Ozone levels also are higher in summer than in winter; and especially in larger, hotter cities, concentrations tend to peak around midday when solar radiation is highest. Exposure to ozone during exercise has been found to increase resting blood pressure, reduce lung function, and decrease exercise capacity.
The risks associated with not exercising at all are far greater than the risks of exercising outdoors; it just takes a little more planning on days and in conditions when pollution is bad. When planning outdoor exercise activities, follow these tips to limit your exposure to pollutants:
- Avoid exercising in areas of heavy traffic, such as along highways and during rush hour.
- During summer, exercise earlier in the morning, when ozone levels and temperatures are not as high.
- Check the domestic or international air-quality ratings to determine if it’s safe to exercise outside. Limit your time outside on Code Red and Code Orange days. Environmental conditions on these days are not healthy, especially for children, the elderly, and people with existing respiratory conditions.
- Exercise indoors when the air quality indicates high ozone and particulate levels.
- Before any demanding physical activity, limit your carbon monoxide exposure by avoiding smoky areas and long car rides in congested traffic.