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: Physical Fitness
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.
Personal trainers can help you safely start and maintain an exercise routine. They can keep you motivated and accountable when it comes to reaching your fitness goals. Finding the right trainer can be challenging but important. Think of it like a date: get to know your potential trainer to find out if you’re compatible. Here are a few things to look for:
- Education/Certifications. These days, anyone can become a personal trainer with a few mouse clicks. Is this person certified through one of the National Commission for Certifying Agencies (NCCA) such as National Federation of Personal Trainers (NFPT), American Council on Exercise (ACE), American College of Sports Medicine (ACSM), or National Academy of Sports Medicine (NASM)? These are widely accepted certifications. Better yet, does the trainer have a 4-year degree in kinesiology or exercise science? Is he/she certified in CPR and first aid?
- Experience. We all have to start somewhere, but experience is helpful. How long has this person been a certified personal trainer? What types of clients does the trainer usually work with? Does he/she have expertise in sports conditioning, pre-natal fitness, or post-rehabilitation? If possible, ask clients (past and/or present) about their personal experiences.
- Personality. You have to enjoy spending time with your trainer so that you’re fully committed to your training routine. Do you prefer a female or a male trainer? Someone close to your age? Choose somebody you like—someone who can motivate you.
- Business practices/Liability. Before you begin, make sure you understand all payment policies and procedures. Are your schedules compatible? What’s the cancellation policy? Does the trainer carry professional liability insurance?
- Fees. Personal trainers can be worth the money, but make sure you understand what you’re paying for. What are the costs? How long is each session? How often will you meet? Is it cheaper if you buy more sessions up front? Will you need to purchase a gym membership?
Heart disease is the #1 cause of death among adults in the U.S.—deadlier than any form of cancer. Risk factors for heart disease include high blood pressure, high cholesterol, diabetes, overweight/obesity, family history, and smoking.
So what can you do to protect yourself protect yourself and your loved ones? First, know your risk factors. There are some things that you can’t change, such as your family history, sex, and age. But there are many things you CAN change through lifestyle choices.
Regular exercise can help you manage many risk factors such as weight, blood pressure, and cholesterol. By now, you’ve probably forgotten about your New Year’s fitness resolutions! Get back on track: commit to at least 30 minutes of moderate to vigorous activity at least 5 days a week. You can even stay active at work!
Remember to make healthy food choices and manage your stress too. Check out the newest Dietary Guidelines for the latest recommendations on eating right. Reboot those fitness and nutrition resolutions to stay ready, resilient, and fit.
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.
Proper running form can help improve your overall efficiency and reduce your risk for injury. We’ve all seen awkward running forms—you can’t help but wince because it looks challenging and sometimes painful to run that way. Following a few simple reminders can keep you injury-free as you reach peak performance.