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
Sneezing, runny nose, watery and/or itchy eyes, and fatigue? Both colds and seasonal allergies make you feel miserable, but you can take steps to avoid or at least take the edge off them. To do so, though, you need to understand which is which. The causes are distinctly different: Colds are caused by viruses, which means they’re contagious. Allergies come from sensitivity to “allergens” such as seasonal pollen, and they’re not contagious.
You can avoid colds through hygiene such as washing your hands thoroughly, especially after touching public surfaces such as handrails. You can avoid “sharing” a cold by covering your mouth or nose when you cough or sneeze or simply by staying home when you’re sick.
To avert seasonal allergies, on the other hand, you must avoid the allergens (mostly airborne) that cause your symptoms. Common allergens in spring include grass and tree pollen. It can be a challenge to exercise and enjoy the outdoors if you have allergies, but it’s not impossible. Here are some tips to help you manage your allergies:
- Know and avoid your allergy triggers. If you aren’t sure what you’re allergic to, have tests done by a healthcare specialist to help you narrow it down. Your doctor also might suggest an antihistamine, inhaler, or medication to help prevent flare-ups.
- Check the air quality in your area every day. If the pollen count (app available!) is high, avoid spending too much time outside, mowing the grass, or exercising outdoors.
- If you must be outside during high-pollen/pollutant times, wear a filter mask to keep particles out of your nose and mouth. If you have to go somewhere, keep your car windows shut.
- Shower when you come back indoors to wash pollen off your skin, hair, and eyelashes.
- Rinse out your nose with a saline spray or solution to help wash away allergens after you’ve been outside.
Many service members exposed to bomb blasts in the field walk away unscathed—or so it would seem. However, there could be some damage they’re not “seeing.”
High-pressure shockwaves from explosive blasts can cause serious eye trauma. In fact, up to 10% of all blast survivors experience significant eye injuries from projectiles thrown into their eyes, eye perforations caused by the high-pressure blast waves, or effects on the eyes associated with traumatic brain injury (TBI). If you were exposed to a blast while in the field but weren’t otherwise injured, don’t wait to set up an appointment with your eye doctor. Prompt medical attention could prevent permanent injury.
Most eye injuries are preventable if you wear protective eyewear on-duty and off-duty. There are many options to choose from the Department of Defense’s (DoD) approved Authorized Protective Eyewear List (APEL). Your vision is extremely important! For more information on protecting your eyesight, visit the Vision Center of Excellence.
Winter isn’t over yet, so here’s a reminder: You can get dehydrated in cold weather. And it isn’t always easy to hydrate, especially when you’re on a mission. If you’re active outside for less than 2 hours, it isn’t likely to be a problem. But if you’re out in the cold for hours or even days for a field deployment, the combination of heavy clothing and high-intensity exercise can lead to sweating, which contributes to dehydration.
You might not even feel as thirsty in cold weather as in the heat, because your cold-weather body chemistry could affect your brain’s ability to tell you when you need liquid. Cold weather also tends to move body fluids from your extremities to your core, increasing your urine output and adding to dehydration.
So when you’re in a cold climate, don’t rely on thirst to tell you when you need to drink. Drink often and before you’re thirsty. One way to determine your hydration status is to check the color and volume of your urine. (Snow makes a good test spot.) Dark, scanty urine indicates dehydration. Ideally, urine should be light yellow.
Water and sports drinks are the best fluids to maintain hydration, even in cold weather conditions. Carbonated and caffeinated beverages (including energy drinks) have a dehydrating effect because they increase urine flow. Also avoid consuming alcohol in cold weather. It might make you feel warm initially, but it can reduce your body’s ability to retain heat.
Enjoy exercising in the cold weather, but be sure to keep your water bottle in tow.
Is it safe to exercise when you’re sick? Those who have strict workout schedules aren’t likely to let the sniffles get in the way of their physical fitness. Exercise benefits include better weight control, improved mood, more energy, and healthier sleep. What’s more, just 30 minutes of regular exercise 5 times each week can improve your heart health and boost your immune system too.
Moderately exercising while you’re sick can be safe and, in certain cases, might actually improve symptoms such as congestion and low-energy. First, you need to determine “how sick is sick.” You can figure this out by using the “neck rule.” If you have symptoms above the neck—including sore throat, nasal congestion, sneezing, or watery eyes—then moderate workouts can continue. If your symptoms are below the neck—including cough, fever, fatigue, or body aches—then rest until the symptoms are gone. You can also use your temperature to determine whether exercising is okay. If you have a temperature of 101°F or higher, moderate or vigorous exercise isn’t safe due to risks of heat-related illnesses and dehydration.
Ultimately, the decision to exercise when you’re sick is up to you. If you’re too weak and fatigued to get out of bed, exercising might not be the best choice. If you have symptoms of a cold and your temperature is below 101°F, light to moderate exercise could be good for you. Make sure to see a doctor if your symptoms don’t improve or get worse.
Don’t let cold weather freeze your exercise routine. Use these tips to stay motivated, safe, and warm.
- Dress in layers. Choose synthetic materials such as polyester or polypropylene that stay close to the skin. Avoid cotton since it soaks up sweat! You can always remove layers as you get warmer.
- Protect your extremities—especially your fingers, toes, and ears. Circulation to these areas decreases in cold weather.
- Check the forecast. Wind chill, snow, and rain can make your body more vulnerable to the outside temperatures. Plan an indoor workout when the wind chill is extreme or the temperature drops below 0°F.
- Apply sunblock. You can still get sunburned in the winter so don’t forget the sunscreen!
- Stay hydrated. When exercising in cold climates, don’t rely on thirst to indicate hydration since you usually don’t feel as thirsty in cold temperatures. You need to stay just as hydrated in cold weather as you do when it’s hot outside.
- Ask your doctor. Certain symptoms might worsen in cold weather if you have asthma, heart issues, or Raynaud’s disease (when specific body parts feel numb due to to cold temperatures or stress). Talk to a healthcare professional about your concerns before heading outside for your cold-weather workout.
Using your military Pro Mask or other commercial mask device as a method of respiratory muscle training (RMT) isn’t going to prepare you for higher elevations. Increasing the strength of your respiratory muscles which help you breathe—your diaphragm and the muscles between your ribs—will improve aerobic fitness, especially for long-duration tasks.
RMT can be achieved through whole-body aerobic exercise, upper-body strength conditioning, and some commercial RMT devices. Studies show that RMT slightly improves performance in those who are already aerobically fit (e.g., military personnel). It offers somewhat more benefit for those less fit or with chronic conditions.
Your Pro Mask was made to protect your lungs, eyes, and face from chemical and biological agents, radioactive particles, and battlefield contaminants. It doesn’t create enough airflow resistance to help improve aerobic capacity. In addition, it wasn’t designed as exercise equipment. There is no scientific evidence that suggests using commercial masks at normal altitudes will improve your performance at high altitudes. Read more about the U.S. Army Research Institute of Environmental Medicine’s (USARIEM) review of Pro Masks and commercial products for exercise training. Check out HPRC’s take on using high-altitude masks and improving work performance at higher elevations.
Blue light is a type of light emitted from all electronic devices and energy-efficient light bulbs. It can give you an energy boost equal to or better than 2 cups of coffee. Blue light may even enhance athletic performance. Sounds great, right? But what if the missing piece of your performance puzzle is sleep? An energy boost during the day may be welcome, but using electronic gadgets at night can be detrimental to your sleep health. The blue light they emit can suppress the secretion of melatonin, a powerful sleep hormone, and disrupt your natural circadian rhythm. Try to manage your exposure to blue light with these tips:
- During the day, take advantage of the bonus your electronic devices give you to boost your attention, reaction times, and mood.
- Shut off all electronic devices at least 2 hours before you need to go to sleep.
- Consider wearing blue-blocking glasses when you need to sleep but can’t avoid blue light.
- If you like having a nightlight, use dim, red bulbs. Red light has less impact on your melatonin levels. (Parents take note for the nightlight in your child’s bedroom.)
One last tip: During the day, get plenty of bright daylight. It makes you feel better during the day, and it will help you sleep better at night.
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. It seems athletes actually run slower on a treadmill than their normal pace outside, yet 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.
If you’re training for an outdoor race, ideally you should run most of your training miles outside. 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. When you want 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 decide to run outside during a cold spell, take a look at our article with tips for staying safe in cold weather and the many resources on cold environments 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!
Exposure to a natural green environment can help reduce your stress levels and improve your health and well-being. So, feeling blue? Go green! Some of nature’s restorative benefits include improved positive mood, energy, and vitality; decreased anxiety, depressive thoughts, perceived stress, and hostility; as well as improved recovery times after surgery and less need for pain meds.
Exposure to nature can also reduce your heart rate, blood pressure, blood sugar, and stress hormones, as well as improve your sleep, immune function, and brain activity. Interestingly, people who live in neighborhoods where streets have more trees report feeling healthier, with fewer symptoms of poor health such as heart attack, stroke, obesity, and diabetes. Neighborhood greenness has also been tied to longer life expectancy.
Depending on where you live, finding a natural environment can be tricky. You can find state and national parks online or look for local parks and gardens in your area. Even walking along a neighborhood street with lots of trees, spending more time viewing nature (through a window), or having indoor plants within view can make you feel better. You may want to experience nature on your own, with a buddy, or with a group of fellow service members or veterans. For group outdoor recreational activities, check out the Sierra Club Outdoors program (or, specifically, their Military Outdoors program). So if you’re feeling stressed, down, or not your usual self, get outside and go green!
Noise-related hearing loss is a tactical risk for individual warriors and unit effectiveness. Being able to hear well is crucial for effective communication and—perhaps more important—for survival. While the military has done extensive research and established standards regarding noise and noise exposure, there are a few things you can do to help minimize your risk of this occupational hazard.
- Wear hearing protectors when firing weapons or traveling in noisy vehicles or aircraft.
- Make sure that earplugs such combat arms earplugs (CAE) fit properly to protect your hearing but still communicate effectively.
- Replace lost or damaged hearing protectors as soon as possible.
- Limit exposure to “annoying noise” during normal daily activities. Trying to ignore noise can increase your heart rate and blood pressure and cause sleep problems and other negative health effects.
- Report any signs of hearing loss as soon as possible.
Hearing loss, including tinnitus, has become an "invisible" injury and an accepted outcome of military service. Blast injuries from improvised explosive devices (IEDs), RPGs, and mortar rounds are the largest cause of hearing loss for forces in Iraq. Compensation payments for hearing loss as the primary disability increased 319% between 2001 and 2006. While there is currently no cure for tinnitus, there are treatments available.
The DoD Hearing Center of Excellence is committed to preventing, treating, and rehabilitating hearing loss and auditory injury for service members and veterans. HCE offers evidence-based clinical care in collaboration with other organizations and Centers of Excellence to improve quality of life for hearing-impaired service members and raise awareness about noise pollution and occupational safety.
Noise pollution may be an inevitable part of serving in the military, but it doesn’t have to leave you with a permanent reminder. Do what you can to help hold on to your hearing.