semper fit

The body prepares for and performs exercise - that is the answer the course key expects. More precisely, exercise physiology is the study of how the body's systems respond to a bout of exercise and adapt to repeated training: exercise raises the demand for energy, the sympathetic nervous system drives an integrated cardiovascular, respiratory, metabolic and muscular response to meet it, and repeated training produces lasting adaptations.

Optimal fitness. Those events are the physical and motor fitness components the Marine Corps measures: FM 21-20 groups speed, agility, muscle power and coordination as "motor" fitness and ties them to survivability on the battlefield, and MCO 6100.13A scores the PFT and CFT as collective measures of general fitness.

Timed runs - that is the answer the course key expects, and it is true as far as it goes: the timed three-mile run is one of the three scored PFT events. Note that no single event measures a Marine's fitness on its own. Under MCO 6100.13A the PFT is scored on three events (pull-ups or push-ups, crunches or plank, and the three-mile run) and the CFT adds three combat-task events, so a full fitness picture takes both tests, not the run alone. The original answer options for this item were not captured, so treat the single-word key with care.

Right; right. Oxygen-poor blood returns through the superior and inferior vena cava into the right atrium, passes the tricuspid valve into the right ventricle, and is pumped through the pulmonary artery to the lungs.

Blood pressure decreases. Consistent aerobic training lowers both systolic and diastolic pressure, acutely after a single session and chronically with continued training, through changes in autonomic balance, nitric oxide availability, the renin-angiotensin system and vascular remodeling.

VO2 - specifically VO2 max, the maximal oxygen consumption, which is calculated from expired-gas data during cardiopulmonary exercise testing and expresses how much oxygen the body can take up and use per minute.

Adenosine triphosphate (ATP). ATP is the cell's energy currency; hydrolysis of its terminal phosphate bond releases the energy used for muscle contraction, ion transport and nerve impulse propagation.

It breaks down sugar molecules called glucose (carbohydrates) to produce energy. Anaerobic glycolysis splits glucose to pyruvate in the cytoplasm without oxygen, yielding only about 2 ATP per glucose versus about 32 by oxidative phosphorylation - fast power, small capacity.

Aerobic. Oxidative (aerobic) metabolism is the pathway used for sustained exercise such as jogging or running; the anaerobic pathways produce ATP faster but can generate far less of it in total.

5 to 15 - that is the answer the course key expects. Note that FM 21-20 specifies a shorter warm-up: five to seven minutes of running in place or slow jogging, stretching and calisthenics performed immediately before the conditioning portion of the workout. Treat five to seven minutes as the doctrinal figure and the course's 5-to-15 range as the number the exam scores.

Improve the joint's range of motion. Flexibility is defined as the ability to move a joint, or any group of joints, through an entire normal range of motion, so flexibility training exists to develop and maintain that range.

Holding a stretch for 30 seconds - that is the answer the course key expects, and 30 seconds is the top of the recommended band. Note that the ACSM 1998 position stand prescribes holding a static stretch for 10 to 30 seconds, at least four repetitions per muscle group, 2-3 days per week; the 2011 ACSM position stand instead prescribes a total of 60 seconds per exercise. Any hold from 10 to 30 seconds is correct practice.

Ballistic. Ballistic stretching uses repetitive bouncing or bobbing motions that rapidly stretch and immediately release the muscle-tendon unit; FM 21-20 adds that it often forces a muscle to stretch too far and directs that individuals and units not use it.

A repetition - one complete cycle of the movement through the full range of motion and back to the starting position. A series of repetitions performed without rest is a set.

Exercise order, exercise selection, frequency, intensity and volume, and rest. These are the resistance-training program variables the ACSM position stand names - choice of resistance (intensity), exercise selection and order, number of sets and repetitions (volume), frequency, and rest period length - and manipulating them is what limits training plateaus.

48. Note that FM 21-20 applies the 48-hour rest to ANY given muscle group, not only small ones, and caps recovery at 96 hours; the same paragraph directs strength training three times a week with 48 hours of rest between workouts for a muscle group.

4 or more. The ACSM position stand on progression models recommends 4-5 days per week for advanced training (2-3 for novice, 3-4 for intermediate), and the full text recommends 4-6 days per week for advanced lifters.

Large muscle, small muscle. Sequencing large muscle groups before small ones (and multiple-joint before single-joint, higher-intensity before lower-intensity) preserves training intensity - if the small assisting muscles are fatigued first they cannot support the heavier large-muscle lift.

Aerobic. The federal Physical Activity Guidelines use the terms interchangeably: aerobic activity is also called endurance or cardio activity - rhythmic movement of the large muscles sustained over time.

Improve the ability of the body to produce energy. Aerobic training increases the number and size of mitochondria in skeletal muscle, expanding the capacity to generate ATP oxidatively - alongside the cardiovascular changes that deliver the oxygen needed to do it.

Decrease in heart rate, measurable increase in stroke volume, and improvement in cardiac output - that is the answer the course key expects. Note the word "immediate" is misleading: DURING an acute bout of exercise heart rate RISES, and it is the trained state that lowers heart rate. Aerobic training lowers resting and submaximal heart rate, raises stroke volume, and preserves or improves cardiac output.

Increased plasma volume of the blood. Endurance exercise and endurance training expand plasma volume (hypervolemia), which raises stroke volume and improves oxygen delivery and thermoregulation.

Maximum; resting. Heart rate reserve is the difference between maximal heart rate and resting heart rate; a training heart rate is then the chosen percentage of that reserve added back to the resting heart rate (the Karvonen method).

20 to 60 minutes of continuous or intermittent aerobic activity, with intermittent bouts of at least 10 minutes accumulated through the day counting toward the total. Duration trades off against intensity - the harder the session, the less time is needed.

Rating of perceived exertion scale, pace, and heart rate. Heart rate is the common standard for estimating training intensity and RPE is a validated adjunct to it - once an individual's heart-rate-to-RPE relationship is known, RPE can substitute for heart rate.

Somewhat hard - roughly 12 to 14 on the 6-20 Borg scale, the exertion adults settle at when training for a cardiorespiratory effect.

50 to 85 percent of heart rate reserve. The ACSM band is 40/50%-85% of heart rate reserve; the 40-49% floor applies only to people who are quite unfit, so 50-85% is the working range for a healthy trained population. (FM 21-20 uses a narrower Army band of 60-90% HRR.)

30 seconds to a few minutes - that is the answer the course key expects. FM 21-20 describes the work interval only as running at a pace slightly faster than race pace for short periods of time, and its worked example uses six to eight 440-yard repetitions at about 1 minute 56 seconds each with recovery periods twice as long as the work interval, which sits inside the course's range.

Get rest, listen to his body, eat a healthy diet, and monitor his resting heart rate. Recovery is one of the named principles of exercise: a hard training day for a component of fitness must be followed by an easier day or a rest day for that component or muscle group, and leaders are warned that injury risk rises with training intensity and duration.

4 to 8 weeks - that is the answer the course key expects, and it will be marked correct. WARNING: the literature does not support "completely detrained" at 4 to 8 weeks. The ACSM position stand reports a measurable drop in cardiorespiratory fitness after only 2 weeks of detraining, a loss of about 50% of the initial VO2max improvement after 4-12 weeks, and a return to near pretraining levels only after 10 weeks to 8 months. So 4-8 weeks is roughly when HALF the gain is gone, not all of it.

III. Grade 1 is a minor tear of a few fibers, grade 2 involves roughly 10% to 50% disruption of the muscle fibers, and grade 3 is a severe injury with 50% to 100% disruption - a palpable defect, complete loss of continuity and retraction.

The heel. The Achilles tendon runs from the gastrocnemius, soleus and plantaris aponeuroses to the calcaneus (heel bone); tendinopathy is typically felt 2 to 6 cm above that insertion, in the hypovascular zone at the back of the heel and lower calf.

Remodeling (the maturation/remodeling phase). It follows the inflammatory and proliferative phases, begins around week 3 and can run up to 12 months while excess collagen degrades and the tissue gains its final strength - about 80% of the original tensile strength.

Protection, rest, ice, compression, and elevation (PRICE). Current clinical sources most often use the four-letter form RICE - rest, ice, compression, elevation - with protection understood as the first step; either way ice and elevation in the first 48 hours reduce pain and swelling, and early controlled motion follows once pain and swelling subside.

Stride length - the ground distance covered by one complete stride. It is not fixed: slope and footing change it, and it shortens going up hills or down steep slopes. FM 21-20 gives a normal foot-march stride of 30 inches at 106 steps per minute.

Cardiovascular system adapts and sweat is produced. Physiologically these are cutaneous vasodilation - opening arterioles and arteriovenous anastomoses so blood carries heat to the skin - and sweating, which removes heat by evaporation.

Communication. Incoherent speech is central nervous system dysfunction, the defining feature of heatstroke alongside a raised core temperature - confusion, ataxia, delirium or seizures. Treat it as a medical emergency, not a communication problem: cool the casualty and call for help.

Convulsions. Heatstroke requires central nervous system dysfunction - ataxia, delirium or seizures (convulsions) - together with a severe rise in core temperature, usually above 40 C. The CDC's public list for heatstroke names high body temperature; hot, red, dry or damp skin; a fast, strong pulse; headache; dizziness; nausea; confusion; and loss of consciousness.

Rubbery legs - that is the answer the course key expects. Clinically the sign is weakness: the CDC lists tiredness or weakness for heat exhaustion, along with heavy sweating; cold, pale, clammy skin; a fast, weak pulse; nausea or vomiting; muscle cramps; dizziness; headache; and fainting. Unlike heatstroke, mental status stays normal.

Wear insulated clothing while exercising - and this one checks out. The Army's Heat Acclimatization Guide tells personnel in cold or temperate climates to mimic the target climate by working out in a warm room wearing sweats, because acclimatization only happens if body temperature rises and profuse sweating is provoked. Note the dose: about two weeks of daily heat exposure, a minimum of roughly two hours a day, with endurance exercise (marching or jogging) rather than strength work - which fits comfortably inside Cpl Levy's 30 days.

Shivering, which decreases fine muscle coordination. Cold degrades motor skill in two ways: shivering itself, and cooling of the hands - manual dexterity falls once finger-skin temperature drops below about 60 F and tactile sensitivity is lost below about 43 F, even when core temperature is normal.

Mental impairment. Even in mild hypothermia (core 32-35 C / 90-95 F) the neurologic signs are cognitive decline, impaired memory and judgment, ataxia and slurred speech; as it deepens, lethargy and CNS depression follow and shivering stops.

Endurance. Aerobic work performance - the Army uses the two-mile run and the twelve-mile road march as examples - falls off above 1,200 m, while short efforts lasting under two minutes are only minimally impaired.

Difficulty in expressing thoughts. Hypoxia degrades a range of neuropsychological functions - mood, judgment, memory, and cognitive and psychomotor task performance - with significant changes generally emerging above 3,000 m and complex tasks affected before simple ones.

A cough producing pink froth. Pink, frothy sputum is a LATE sign - HAPE starts as exertional dyspnea, dry cough and falling exercise tolerance, and the hallmark is dyspnea at rest, especially at night. Descend before it reaches the frothy-sputum stage.

10 to 14 days - that is the answer the course key expects, and it is a fair working figure. Note the fuller picture from TB MED 505: about 70-80% of the respiratory component of acclimatization happens in a week to 10 days and 80-90% of overall acclimatization by 2 weeks to a month, but maximum or complete acclimatization can take months to years. Acclimatization is also elevation-specific and is lost within days to a week after returning to lower ground.

Cancer. The estimate comes from the American Cancer Society's nutrition and physical activity guidelines, which attributed about one third of U.S. cancer deaths to diet and physical activity habits combined. Note that this is an older figure and that diet is not isolated from physical activity or body weight in it; more recent ACS estimates put the share of cancer deaths attributable to excess body weight, alcohol, inactivity and unhealthy diet together at well under one third.

Diabetes - type 2 diabetes specifically. Eating patterns high in vegetables and fruits are associated with reduced risk of type 2 diabetes, and also of cardiovascular disease, certain cancers, overweight and obesity.

1 to 2 lbs per week. Gradual, steady loss at that rate is more likely to be kept off than rapid weight loss.

Sugar - that is the answer the course key expects, and it is right in the chemical sense: every carbohydrate is built from simple sugar units (monosaccharides such as glucose). Note the term is broader than table sugar. Carbohydrate is an umbrella term covering sugars, starches and fiber - monosaccharides, disaccharides, oligosaccharides and polysaccharides - so "sugars, starches and fiber" is the fuller answer, and dietary carbohydrate is not the same thing as added sugar.