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HPRC Fitness Arena: Physical Fitness
This is the third and final article in HPRC’s series about training for Physical Fitness (PFT) and Physical Readiness Tests (PRT). The last basic component involves keeping your body fit for movement, especially your joints and the surrounding muscles, tendons, and ligaments. For coordinated and efficient movements, you need give-and-take between the mobility and stability of these parts.
Preventing injuries also requires mobility and stability of your musculoskeletal system. To improve and maintain your mobility, you need to incorporate stretching into your regular training regimen, along with your aerobic and muscular-strength exercises. The addition of muscular-strength exercises to flexibility exercises addresses your joint-stability needs. Read more...
Another basic component of Physical Fitness (PFT) and Physical Readiness Tests (PRT) training involves muscular strength and endurance, but as with aerobic conditioning, you need to develop it over time, not just before your fitness tests. Whether you’re training or in the field, and even when you’re not thinking about it—such as moving ammunition boxes into a transport—your muscular strength and endurance are essential components of your overall fitness.
But training to improve muscular strength is not the same as training for muscular endurance. Muscular strength is the amount of force that a muscle can produce with a single maximum effort. Muscular endurance is the ability to sustain a muscle contraction over a period of time, or to repeatedly contract a muscle over a period of time.
Learn how to use the FITT principle to develop a muscular fitness routine that will build both strength and endurance to prepare for PFT/PRT and beyond. Read more...
Preparation for your Physical Fitness (PFT) and Physical Readiness Tests (PRT) takes time and discipline. Training for the test isn’t something you should start the month before the test, and the habits you develop leading up to the test should be ones you continue even after the test. Weekend warriors and procrastinators are at greater risk for injury, and it’s likely that your performance will be less than optimal when it comes time for the test.
If you’re just getting back into shape, be sure to do it gradually. Once you’ve resumed a regular exercise routine, you might notice some aches and pains. Listen to your body. Watch out for symptoms of common athletic injuries such as overuse injuries and knee pain. It’s important to address these issues early to minimize any damage and get you back in action as soon as possible. Maintaining your exercise routine after the PFT/PRT and challenging yourself along the way will keep you in warrior-athlete shape year round and prevent deconditioning.
HPRC provides a series of articles with guidelines to help you prepare for the PFT/PRT, beginning with this one on aerobic conditioning. Read more...
On a daily basis, girls’ physical activity levels are lower than boys’ of the same age. They need extra support from their parents to get moving and find opportunities for physical fitness. A lack of physical activity can have negative consequences in the long term, such as poorer hand-eye coordination and worse overall health. But exercise isn’t just good for your child’s body; it’s also linked to better academic achievement.
One reason girls get less exercise is because they may not be offered opportunities to engage in physical fitness. Parents might assume their daughters don’t like sports and then don’t suggest they participate. Encouragement from parents matters. Don’t assume your daughter isn’t interested in physical fitness, even if she sometimes says she isn’t! Break up the times your daughter is just sitting around by getting her to go for a walk or move around the house. Ask her to help with tasks at home that require some physical activity. Encourage your daughter to enroll and stay involved in organized sports from a young age. Brainstorm physical activities she might enjoy. There’s trampoline, fencing, hip-hop dance, lacrosse, martial arts, soccer, ice hockey, skateboarding, rowing, swimming, yoga, or tennis, to name a few.
Remember that kids take their cues from their parents. Set an example by being physically active yourself, and your children will likely follow suit. All kids—boys and girls—need at least 60 minutes if physical activity a day. Not sure what type of exercises your children should be doing? Check out HPRC’s “Put some fun in your children’s fitness” for some great ideas.
How do you know how much weight to lift when you start a resistance-training program? Most programs are designed around lifting a percentage of your maximum strength.
First, you need to find out what your maximum strength is. A popular method is the one-repetition maximum test (1RM): the most weight you can press once but not twice. You can also do multiple-repetition tests for a reliable estimate of maximum strength. A 5-repetition test seems to be accurate, but more than 10 reps is unreliable.
This instructional video demonstrates the American College of Sports Medicine’s (ACSM) protocol for a 1RM test. ACSM’s protocol can also be applied to a multiple-repetition test. For example, determine the most weight you can lift 5 times, but not 6 times, for a 5-rep max test. If you have doubts about whether this is the right test for you, be sure to consult a healthcare professional.
The second step is to determine what amount of weight—as a percentage of your 1RM—you should use to improve your muscular strength and endurance. Typically, your muscular strength should improve if you use 60–80% of your 1RM. You should be able to improve your muscular endurance using about 50% of your 1RM. Once you’ve assessed your maximum strength, use this conversion chart from the National Academy of Sports Medicine (NASM) to determine your 1RM percentages.
An important thing to know about stress fractures is how to avoid them. A stress fracture is a tiny crack in a bone that happens when your muscles can’t absorb shock and transfer stresses to the bone. Most occur in the lower extremities, especially the lower leg and foot.
A stress fracture is usually an overuse injury that develops over a long period of time—from weeks to months. They’re especially common among military recruits, in about 3% of men and 9% of women. And since it can take several weeks to months for a stress fracture to heal, the best approach is to avoid getting one. Here are some tips for prevention:
- Use the progression principle of training: Gradually increase your training intensity, usually by no more than 10% weekly if you exercise 3 or more days a week. Slowly incorporate higher-stress activities such as jumping and interval training into your workout. Set incremental goals to help you develop your training routine step-by-step.
- Check your footwear and make sure it matches your training routine. Replace old or worn footwear.
- Check your form. Are you moving properly when you exercise or does your form put you at risk of injury?
- Pay attention to early signs of injury. Unusual muscle soreness and other aches and pains can be a sign of injury and/or imbalances that could worsen if they aren’t addressed early.
- Monitor your diet, specifically calcium and vitamin D intake. To learn more, read the National Institute of Health’s Dietary Supplement Fact Sheet on calcium and HPRC’s article on vitamin D.
It’s important to recognize a stress fracture and get medical help early, as described by the American Academy of Orthopaedic Surgeons. The Mayo Clinic provides more information on symptoms. And check out HPRC’s Injury Prevention section for more on how to avoid injury.
Since pull-ups are tough and require a lot of strength, HPRC just created a training program to help you meet the challenge. Achieving a pull-up might be easier for some, but more difficult for others, especially women. Other factors such as body fat, arm length, and height can affect your ability to achieve a pull-up too.
But what that means is—with the right training—you can do it! Check out HPRC’s Pull-up Progression Program for exercises aimed at increasing your strength and helping you achieve your first pull-up.
“Long slow-distance runs,” the coaching phrase goes, “make long slow-distance runners.” A leisurely long run isn’t bad for you—it just means that if you want to run faster, you have to train faster. Mix it up instead and incorporate speed workouts into your runs: interval, tempo, and fartlek.
Always include a warm-up and cooldown with your workout. Limit speed workouts to twice a week and get enough rest and recovery in between. Actively rest by going on a lighter run or bike ride, or even doing some yoga. Learn more about how speed workouts can ramp up your performance. Read more...
Between the growing epidemic of childhood obesity and the continuing popularity of video games among children, does exergaming actually count as physical activity? Exergaming, or exercise video gaming, is popular among children and adults because it offers entertainment and physical activity. Exergames include:
- Virtual cycling
- Interactive climbing machines
- Aerobics, dancing, and floor games for multiple video game platforms
- Mobile exercise games for smartphones and tablets
While it’s certainly fun, studies suggest that exergaming is not the best form of exercise for kids. It does increase energy expenditure (compared to rest), but it’s not necessarily enough to meet your children’s exercise needs. For example, when compared to a phys ed class, exergaming fell short. For the most part, kids who play exergames don’t burn enough calories or increase their heart rates enough to make up for exercising.
The good news about exergaming is that it can increase motivation and keep children engaged. It could be a great starting point for inactive children needing to begin a physical activity routine. It can be part of the daily-recommended doses of exercise and physical activity for kids and teens too. Families could find it as a fun alternative to sitting on the couch and watching a movie or TV show. Exergaming might be better than sitting and playing video games, but it shouldn’t replace more vigorous activities such as outside play. Save the exergaming for the next rainy or snowy day!
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.