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: Total Force Fitness
Following in the wake of the Food and Drug Administration’s warning letters to manufacturers and distributors of dietary supplements containing DMAA, the Army announced that its own study on the effects of DMAA on soldiers will continue. Read about the announcement and more in the recent Stars and Stripes article. For more information about the FDA’s action, you can read HPRC’s post, which also includes a link to the FDA news release.
When you begin a resistance training program, how do you know how much weight you should be lifting? Most muscular fitness programs are designed around lifting a percentage of your maximum strength.
The first step in this process is to determine what your maximum strength is. A popular technique for assessing muscular strength is the one-repetition maximum test (1RM), or the maximum amount of weight you can press once but not twice. Alternatively, multiple repetition tests can be performed as a reliable estimate of maximum strength. One study found that a five- repetition test was the most accurate, but no more than 10 reps should be used to estimate strength. This instructional video will demonstrate the ACSM protocol for a 1RM test. This protocol can also be applied to a multiple-repetition test. For example, determine the maximum amount of weight you are able to lift five times, but not six times, for a five-rep max test. If you have doubts about whether this is the right test for you, be sure to consult your doctor.
The second step is to determine what percentage of your 1RM, in weight, you should use to improve your muscular strength and endurance. Typically, improvements in muscular strength are seen when using 60-80% of your 1RM. Increased muscular endurance is achieved using about 50% of your 1RM. Read more on muscular fitness and more details on how to train for each here. Once you have assessed your maximum strength, use this conversion chart from the National Academy of Sports Medicine (NASM) to determine percentages of your 1RM.
The Food and Drug Administration (FDA) sent warning letters to manufacturers and distributors of dietary supplements containing 1,3-dimethylamylamine (DMAA) due to lack of safety evidence provided before marketing. The FDA states that information about the safety of DMAA as a dietary supplement ingredient has not been identified. For more information, see the FDA News Release and HPRC’s latest on Dietary Supplement Products Containing DMAA.
Federal food safety information from the U.S. Food and Drug Administration (FDA) and the U.S. Department of Agriculture (USDA) is now provided on HPRC’s Nutrition domain page via a new “widget” (app) from the U.S. Department of Health and Human Services. Recent food safety alerts and recalls are automatically displayed and updated as new recalls, etc., are added. Please see this new feature by visiting HPRC’s nutrition section.
A recent article in the New York Times looks at the combination of neuroscience and exercise. A new theory suggests that your brain, not your hormones, increases or decreases your appetite after a workout. Researchers at California Polytechnic State University studied different areas of the brain that control whether we want and like food and how these areas are affected by exercise or sitting still.
Scientists found that “responsiveness to food cues was significantly reduced after exercise.” Compared to sitting for an hour, exercisers were much less interested in food, even ice cream sundaes. The subjects in the study were in their 20s and fit enough to sustain strenuous exercise for an hour. This is in contrast to a study that found the same areas in the brain were excited in an overweight and sedentary population after exercise, causing them to want and eat more food.
While the effect is still unclear and more variables need to be tested, researchers conclude that exercise has a definite impact on how your brain responds to food.
PsychCentral’s March 2012 "Ask the Therapist" article addresses how mindfulness relates to military performance—especially important now that the military has been incorporating mindfulness tactics for enhancing Warfighter mental and physical resilience. Of particular note is a study from the Journal of Clinical Psychology that demonstrated significant improvements in PTSD symptoms, depression, etc. in veterans after completing a Mindfulness-Based Stress Reduction (MBSR) program. The article also noted other studies that showed long-term stress-reduction, well-being, and positive experiences. Simply put, acknowledging emotional pain helps you overcome it. You are then able to focus and communicate with loved ones more effectively.
If you’d like to learn more about meditation and mindfulness, check out the Mind Tactics section of the HPRC website, which contains many resources related to meditation and mindfulness, as well as resources related to mental fitness, mental toughness, and resilience.
Good cholesterol, or high-density lipoprotein (HDL), helps prevent fat and cholesterol from clogging your arteries. A higher HDL number (> 60 mg/dl of blood) is better. Low-density lipoprotein (LDL) is considered bad cholesterol. It carries cholesterol to your arteries and can cause them to become blocked. A lower LDL number (< 100 mg/dl) is better. High-LDL or low-HDL cholesterol levels are major risk factors for heart disease and stroke. Visit this American Hearth Association web page for more information.
The latest news on DMAA includes the New Zealand government’s ban just placed on DMAA-containing products. DMAA has already been declared a drug in Canada and is banned by the World Anti-Doping Agency, the United States Anti-doping Agency (USADA), collegiate sports teams, and most professional sports teams.
HPRC has again updated its list of DMAA-containing dietary supplements, including a number of additions as well as some products that have been discontinued or reformulated. The additions mostly represent lesser-known products that have been around a while, but surprisingly there are a couple new products too. And we have added two new “aliases” to the list of other names for DMAA. To download the list, click on this link to “Dietary Supplement Products Containing DMAA.”
In a recent study investigating risk factors for discharge from Army Basic Combat Training (BCT), researchers concluded that increased risk for both men and women was associated with failure on the initial two-mile run test. The current Physical Fitness Tests (PFT) or Physical Readiness Test (PRT) use a one and a half to two-mile run test to assess cardiovascular, or aerobic, fitness.
When mapping out a fitness program, learn the components of the FITT principle and apply them for each type of training. FITT stands for “frequency,” or how often; “intensity,” or how hard; “type,” or the kind of activity; and “time,” or how long. Progression (see below) is also an important part of an exercise plan. Using the FITT Principle, here are some guidelines to help optimize your cardiovascular fitness.
Frequency. The U.S. Surgeon General and other U.S. government agencies recommend physical activity on three or more days a week.
Intensity. According to updated guidelines The American College of Sports Medicine (ACSM) recommends adults engage in moderate-intensity exercise (i.e., at 40-60% Heart Rate Reserve (HRR)) five days a week or vigorous-intensity exercise training (i.e., at ≥ 60% HRR) three or more days a week. They also recommend a combination of moderate- and vigorous-intensity exercise. You can use this calculator from Kirtland AFB to determine your HRR.
Type. ACSM defines aerobic activities as being continuous, rhythmic, and using large muscle groups, such as your lower and upper body muscles. Examples of these kinds of activities are running, biking, swimming, rowing, and jump roping.
Time. The Surgeon General, ACSM, and American Heart Association recommend expending at least 1,000 calories per week through exercise (i.e., in addition to calories burned through normal everyday activities). This can be achieved through moderate-intensity exercise, as described above, and should last about ≥ 30 minutes per day for a total of ≥ 150 minutes per week; or with vigorous-intensity exercise for ≥20 minutes per day for a total of ≥75 minutes per week. The maximum safe duration is unknown, but exercise lasting more than an hour and a half increases risk of overtraining and/or overuse injuries such as stress fractures.
Progression. During the initial phase of an exercise program, ACSM recommends increasing duration (minutes per session) gradually. Increasing 5-10 minutes every one or two weeks over the first four to six weeks of an exercise program is reasonable for healthy adults. After an exercise routine has been maintained for one month or longer, it is reasonable to gradually increase frequency, intensity, and/or time over the next four to eight months. As a general rule of thumb, though not scientifically backed, increasing your workloads or volume by 10% will also help you gradually progress your exercise program.
Due to the repetitive and rhythmic nature of aerobic exercise, overuse injuries can occur as a result of your training. Cross training—training with a variety of aerobic exercises—is recommended. Examples of this would be alternating running, swimming, and rowing exercise sessions.
Part two of this series (upcoming) will address the muscular strength component of PFT/PRT.
It’s normal for relationships to go through ups and downs, and at times it can be difficult to know whether to work through things alone or seek help from a professional. The Navy and Marine Corps Public Health Center's website has a list of questions to help you assess your relationship. Given your responses, they suggest whether you should see a counselor or doctor or try self-help strategies. Common issues that couples face include communication difficulties, power struggles, money conflicts, and differences in parenting styles. You'll find self-help tips in the following areas:
- Communication. Learn how to communicate more effectively with “I”-statements, perspective taking, timing, omitting distractions, and sharing issues.
- Jealousy. Learn how to handle jealousy, with tips such as focusing on the importance of the relationship, expressing your emotions, communicating, being supportive, and helping to solve problems together.
- Sex. Talk to one another about your needs so you can work together on areas where your desires are compatible.
- Money. More tips help you handle money matters such as budgeting, credit history, and credit card advice.
For additional information, you can also visit the Relationship Skills section of HPRC’s website.