EXAM 2: Strength and conditioning

Respiratory adaptations to aerobic training

-Ventilatory adaptations are highly specific to activities that involve the type of exercise used in training. Training adaptations include increased tidal volume and breathing frequency with maximal exercise

oestoporosis

A bone mineral density below −2.5 SD of the young adult mean.

Mistakes that can lead to anaerobic overtraining

Chronic use of high intensity or high volume or a combination of the two Too rapid a rate of progression

Youth Resistance Training

Clinicians, coaches, and exercise scientists now agree that resistance exercise can be a safe and effective method of conditioning for children

Chronic changes in resting hormonal concentrations

Consistent chronic changes in resting hormonal concentrations are less likely.

chronic changes in the acute hormonal response

Consistent resistance training may improve the acute hormonal response to an anaerobic workout.

Fiber type transitions

Continuum of fiber types: I, Ic, IIc, IIac, IIa, IIax, IIx

Local Muscular Endurance

Cross-sectional data in anaerobic athletes have shown enhanced muscular endurance and subsequent muscular adaptations consistent with improved oxidative and buffering capacity. Skeletal muscle adaptations to anaerobic muscular endurance training include increased mitochondrial and capillary number, fiber type transitions, buffering capacity, resistance to fatigue, and metabolic enzyme activity.

•What are the markers of aerobic overtraining?

Decreased performance Decreased percentage of body fat Decreased maximal oxygen uptake Altered blood pressure Increased muscle soreness Decreased muscle glycogen Altered resting heart rate

hormonal changes in peripheral blood

large increases in hormone concentration indicate higher probabilities for interactions with receptors

Detraining

loss of accumulated physiological adaptations following the cessation of anaerobic training. •Can also occur when there is a substantial decrease in training frequency, volume, or intensity.

In terms of absolute strength, women are generally weaker than men because of

lower quantity of muscle.

The intensity of training is one of the most important factors in

improving and main-taining aerobic power.

catecholamine training adaptations

- Heavy resistance training has been shown to increase the ability of an athlete to secrete greater amounts of epinephrine during maximal exercise - Because epinephrine is involved in metabolic control, force production, and the response mechanisms of other hormones (such as testosterone, GHs, and IGFs), stimulation of catecholamine's is probably one of the first endocrine

Muscle Fiber Transitions

- Muscle fiber transitions occur during training. - This means that a shift of the type of myosin adenosine triphosphatase (ATPase) and heavy chains takes place during training. - Transformations from IIx to IIax to IIa can be seen, and then small percentages change to IIac and IIc. - Exercise activities that recruit motor units with Type IIx muscle fibers initiate a shift toward IIa fibers.

Program design considerations for children

- consider quality of instruction and rate of progression - focus on skill improvement, personal successes, and having fun.

Acute aerobic exercise results in

- increased cardiac output - increased oxygen uptake - increased systolic number in bp - decreased diastolic number in bp - increased blood flow to muscles - increased heart rate

Youth Resistance Training Guidelines

- static stretching exercises should be performed after resistance training. - carefully monitor each child's tolerance to the exercise stress. - begin with light loads - increase the resistance gradually (e.g., 5% to 10% os strength improves) - depending on needs and goals, one to three sets of 6 to 15 reps on a variety of exercises can be performed. - advanced multipoint exercises may be incorporated into the program if appropriate loads are used and the focus remains on proper from. - 2 or 3 nonconsecutive training sessions per week are recommended - adult spotters should be nearby to actively assist the child. - the resistance training program should be systematically carried throughout the year

endocrine adaptations to aerobic exercise

-Aerobic exercise leads to increases in hormonal circulation and changes at the receptor level. -High-intensity aerobic endurance training augments the absolute secretion rates of many hormones in response to maximal exercise. Trained athletes have blunted responses to submaximal exercise

respiratory responses to aerobic exercise

-Aerobic exercise provides for the greatest impact on both oxygen uptake and carbon dioxide production, as compared to other types of exercise. -Significant increases in oxygen delivered to the tissue, carbon dioxide returned to the lungs, and minute ventilation provide for appropriate levels of alveolar gas concentrations during aerobic exercise.

•What are the safety recommendations for resistance training for seniors?

-All participants should be prescreened. -Warm up for 5 to 10 minutes before each exercise session. -Perform static stretching exercises before or after,or both before and after, each resistance training session. -Use a resistance that does not overtax the musculoskeletal system. -Avoid performing the Valsalva maneuver. -Allow 48 to 72 hours of recovery between exercise sessions. -Perform all exercises within a range of motion thatis pain free. -Receive exercise instruction from qualified instructors.

Acute cardiovascular responses to anaerobic exercise

-An acute bout of anaerobic exercise significantly increases the cardiovascular responses, especially if the individual uses the Valsalva maneuver.

motor performance

-Anaerobic training enhances motor performance; the magnitude of change is based on the specificity of the exercises or modalities performed. -Resistance training has been shown to increase •Running economy •Vertical jump •Sprint speed •Tennis serve velocity •Swinging and throwing velocity Kicking performance

Flexibility

-Anaerobic training potentially can have a positive impact on flexibility, primarily if the individual has poor flexibility to begin with. -The combination of resistance training and stretching appears to be the most effective method to improve flexibility with increasing muscle mass.

How can we reduce the risk of overuse injuries in youth?

-Before sport participation, young athletes should be evaluated by a sports medicine physician. -Parents should be educated about the benefits and risks of competitive sports. -Parents should understand the importance of preparatory conditioning. -Children and adolescents should be encouraged to participate in year-round physical activity.

blood doping

-Can improve aerobic exercise performance and may enhance tolerance to certain environmental conditions -Is unethical and poses serious health risks

Altitude adaptations

-Changes begin to occur at elevations greater than 3,900 feet (1,200 m): •Increased pulmonary ventilation (hyperventilation) •Increased cardiac output at rest and during submaximal exercise due to increases in heart rate -Values begin to return to normal within 2 weeks. Several chronic physiological and metabolic adjustments occur during prolonged altitude exposure.

aerobic capacity

-Heavy resistance training does not significantly affect aerobic capacity unless the individual is initially deconditioned. -The exception is in relatively untrained people, who can experience increases in VO2max ranging from 5% to 8% as a result of resistance training. -Circuit training and programs using high volume and short rest periods (i.e., 30 seconds or less) have been shown to improve VO2max.

Power

-Heavy resistance training with slow velocities of movement leads primarily to improvements in maximal strength. Power training increases force output at higher velocities and rate of force development.

Heavy Resistance Exercise and Hormonal Increases

-Hormones are secreted before, during, and after the resistance exercise bout due to the physiological stress of resistance exercise - As a few as one or two heavy resistance exercise sessions can increase the number of androgen receptors in the muscle

developmental changes in muscular strength

-In boys, peak gains in strength typically occur about 1.2 years after peak height velocity and 0.8 years after peak weight velocity. -In girls, peak gains in strength also typically occur after peak height velocity, although there is more individual variation in the relationship of strength to height and body weight. -On average, peak strength is usually attained by age 20 in untrained women and between the ages of 20 and 30 in untrained men.

cardiovascular adaptations

-Increases in maximal cardiac output, stroke volume, and fiber capillary density -Increased parasympathetic tone leads to decreases in resting and submaximal exercise heart rates -

Testosterone

-Interacts with receptors on neurons -Increases the amount of neurotransmitters -Influences structural protein changes -Interact directly with skeletal muscle itself -Protein synthesis -Increased calcium release

testosterone in men

-Levels are higher during the day compared to night. Exercise later in the day is more effective for increasing overall testosterone concentrations over an entire day.

•Age-related changes in musculoskeletal health

-Loss of bone and muscle with age increases the risk for falls, hip fractures, and long-term disability. -Bones become fragile with age because of a decrease in bone mineral content that causes an increase in bone porosity. -After age 30 there is a decrease in the cross-sectional areas of individual muscles, along with a decrease in muscle density and an increase in intramuscular fat.

components of mechanical load that stimulate bone growth:

-Magnitude of the load (intensity) -Rate (speed) of loading -Direction of the forces -Volume of loading (number of repetitions)

age and sex

-Maximal aerobic power decreases with age in adults. -Aerobic power values of women range from 73% to 85% of the values of men. The general physiological response to training is similar in men and women

anaerobic training and bone growth

-Muscle strength and hypertrophy gains increasethe force exerted on the bones, which may result ina corresponding increase in bone mineral density (BMD) or the quantity of mineral deposited in agiven area of bone.

muscular adaptations to aerobic training

-One of the fundamental adaptive responses to aerobic endurance training is an increase in the aerobic capacity of the trained musculature. -This adaptation allows the athlete to perform a given absolute intensity of exercise with greater ease after aerobic endurance training.

what are markers of overtraining

-Psychological effects: decreased desire to train, decreased joy from training -Acute epinephrine and norepinephrine increases beyond normal exercise-induced levels (sympathetic overtraining syndrome) -Performance decrements, although these occur too late to be a good predictor

Other Muscular Adaptations

-Reduced mitochondrial density -Decreased capillary density -Increased buffering capacity (acid-base balance) -Changes in muscle substrate content and enzyme activity

body composition

-Resistance training can increase fat-free mass and reduce body fat by 1% to 9%. -Increases in lean tissue mass, daily metabolic rate, and energy expenditure during exercise are outcomes of resistance training.

growth hromone (GH)

-Secreted by the pituitary gland -Interacts directly with target tissues, which include bone, immune cells, skeletal muscle, fat cells, and liver tissue -GH release patterns altered by age, gender, sleep, nutrition, alcohol consumption, and exercise

•Age-related changes in neuromotor function

-Seniors are at increased risk of falling. •Factors include decreased muscle strength and power, decreased reaction time, and impaired balance and postural stability. -Research shows that physical activity interventions can be effective in improving neuromotor function and preventing falls.

•Responsiveness to resistance training in older adults

-Seniors who participate in progressive resistance training programs show significant improvements in •Muscular strength and power •Muscle mass •Bone mineral density •Functional capabilities

Tapering

-The planned reduction of volume in training that occurs before an athletic competition or a planned recovery microcycle.

Adaptations of tendons, ligaments, and fascia to anaerobic training

-The primary stimulus for growth of tendons, ligaments, and fascia is the insult from mechanical forces created during exercise. -The degree of tissue adaptation is proportional to the intensity of exercise. -Consistent anaerobic exercise that exceeds the threshold of strain stimulates connective tissue changes.

General bone physiology

-Trabecular bone responds more rapidly to stimuli than does cortical bone. -Minimal essential strain (MES) is the threshold stimulus that initiates new bone formation. -The MES is approximately 1/10 of the force required to fracture bone.

Main physiological roles of GH

-decreases glucose utilization -inc protein syn -inc collagen syn -stim cartilage growth -enhances immune cell fxn -inc lipolysis (fat breakdown)

Roles of catecholamines

-inc force production -inc muscle contraction rate -inc bp -inc energy availability -inc muscle blood flow -augment secretion rates of other hormones

Hyperplaisa

-increase in the number of muscle fibers via longitudinal fiber splitting.

Cortisol exerts its major catabolic effects by

-stimulating the conversion of amino acids to carbohydrates, -increasing the level of proteolytic enzymes (enzymes that break down proteins), -inhibiting protein synthesis -suppressing many glucose-dependent processes such as glycogenesis and immune cell function. Has a greater effect on Type II fibers than Type I fibers

How can athletes stimulate bone formation?

1. Use exercises that directly load particular regions of the skeleton. 2. Use structural exercises to direct force vectors through the spine and hip and allow the use of greater absolute loads in training. 3. Overload the musculoskeletal system and progressively increase the load as the tissues become accustomed to the stimulus. 4. Vary exercise selection to change the distribution of the force vectors to continually present a unique stimulus.

hormonal markers of anaerobic overtraining

Acute epinephrine and norepinephrine increases beyond normal exercise induced level

tidal volume

Amount of air that moves in and out of the lungs during a normal breath

Adaptations in Endocrine System

Amount of synthesis and storage of hormones Duration of liver and other tissue clearance Number of receptors in tissue Degree of interaction with the cell nucleus

anaerobic training and electromyography studies

An increase in EMG indicates greater neural activation. Studies have shown strength and power increases of up to 73%. Advancement in training contributes to further gains in strength and power. Dramatic increases in neural adaptations take place early in the training program

Chronic cardiovascular adaptations at rest

Anaerobic training leads to decreases or no change in resting HR and BP. Resistance training alters cardiac dimensions.

Neuromuscular reflex potentiation

Anaerobic training may enhance the reflex response, thereby enhancing the magnitude and rate of force development.

hyperoxic breathing

Breathing oxygen enriched gas mixtures during rest periods or following exercise may positively affect exercise performance

Acute anaerobic exercise results in increased

Cardiac output Stroke volume Heart rate Oxygen uptake Systolic blood pressure Blood flow to active muscles

Hormones

Chemical messengers that are synthesized, stored, and released into the blood by endocrine glands and certain other cells.

Chronic adaptations of the acute cardiovascular response to anaerobic exercise:

Chronic resistance training reduces the cardio-vascular response to an acute bout of resistance exercise of a given absolute intensity or workload

neural adaptations to aerobic exercise

Efficiency is increased and fatigue of the contractile mechanisms is delayed.

resting oxygen uptake

Estimated at 3.5 ml of oxygen per kilogram of body weight per minute (ml·kg-1·min-1); this value is defined as 1 metabolic equivalent (MET).

Bilateral deficit in untrained individuals

Force produced when both limbs contract together is lower than sum of forces produce when contracting unilaterally

Free Testosterone and Sex Hormone-Binding Globulin

Free testosterone accounts for only 0.5% to 2% of total testosterone; thus higher total testosterone concentration allows for more free testosterone. Heavy resistance exercise (e.g., six sets of 10 repetitions at 80% of 1RM) can acutely increase free testosterone in men and women, although the increase is much smaller for women.

growth hormone responses to stress

GH responds to exercise stressors, including resistance exercise. GH response depends on load, rest, and volume of exercise.

Biochemical responses to overtraining

High training volume results in increased levels of creatine kinase, indicating muscle damage. Muscle glycogen decreases with prolonged periods of overtraining.

anaerobic training

High-intensity, intermittent bouts of exercise such as weight training; plyometric drills; and speed, agility, and interval training.

Process of Hypertrophy

Increase in synthesis of contractile proteins actin and myosin within myofibril and increase in number of myofibrils within a muscle fiber. New myofilaments added to external layers of myofibril resulting in increase in diameter

Endocrine responses to overtraining

Overtraining may result in a decreased testosterone-to-cortisol ratio, decreased secretion of GH, and changes in catecholamine levels.

potential benefits to youth resistance training

Participation in a youth resistance training program can influence many health- and fitness-related measures

Polypeptide Hormone Interactions

Made of chains of amino acids Examples: growth hormone and insulin

Cartilage adaptations to anaerobic training

Main functions of cartilage - Provide a smooth joint articulating surface - Act as a shock absorber for forces directed through the joint - Aid in the attachment of connective tissue to the skeleton - Cartilage lacks its own blood supply and must depend on diffusion of oxygen and nutrients from synovial fluid. - Therefore, joint mobility is linked with joint health. - Movement about a joint creates changes in pressure in the joint capsule that drive nutrients from the synovial fluid toward the articular cartilage of the joint.

adaptations of motor units

Maximal strength and power increases of agonist muscles result from an increase in recruitment, rate of firing, synchronization of firing, or a combination of these factors.

central adaptations

Motor cortex activity increases when the level of force developed increases and when new exercises or movements are being learned. Many neural changes with anaerobic training take place along the descending corticospinal tracts.

muscle and bone growth in children

Muscle mass steadily increases throughout the developing years. During puberty, increases in testosterone production in boys result in a marked increase in muscle mass, whereas in girls an increase in estrogen production causes increased body fat deposition, breast development, and widening of the hips. When the epiphyseal plate becomes completely ossified, the long bones stop growing.

combining resistance and aerobic endurance training may interfere with strength and power gains

Primarily if the aerobic endurance training is high in intensity, volume, and frequency.

psychological factors in overtraining

Psychological alterations are often observed before actual decrements in performance occur.

•Aerobic endurance training results in

Reduced body fat Increased maximal oxygen uptake Increased running economy Increased respiratory capacity Lower blood lactate concentrations at submaximal exercise Increased mitochondrial and capillary densities Improved enzyme activity

hormone receptor changes

Resistance training has been shown to upregulate androgen receptor content within 48 to 72 hours after the workout.

structural and architectural changes

Resistance training increases myofibrillar volume, cytoplasmic density, sarcoplasmic reticulum and T-tubule density, and sodium-potassium ATPase activity. Sprint training enhances calcium release. Resistance training increases angle of pennation.

Fiber size changes

Resistance training results in increases in both Type I and Type II muscle fiber area. Type II fibers have greater increases in size than Type I fibers

Cortisol resistance exercise responses

Responds to resistance exercise protocols that create a dramatic stimulus to anaerobic metabolism. Increases in cortisol might not have negative effects in men after a period of training to which the body has adapted; adaptation "disinhibits" cortisol at the level of the testis, thereby maintaining testosterone's primary influence on its nuclear receptors.

biological age

Skeletal age, physique maturity, sexual maturation

Muscular Adaptations

Skeletal muscle adapts to anaerobic training primarily by increasing its size, facilitating fiber type transitions, and enhancing its biochemical and ultra-structural components. These changes result in enhanced muscular strength, power, and muscular endurance.

Acute anabolic hormonal responses

The acute anabolic hormonal response to anaerobic exercise is critical for exercise performance and subsequent training adaptations. Upregulation of anabolic hormone receptors is important for mediating the hormonal effects.

stroke volume

The quantity of blood ejected with each beat.

what leads to muscle growth and strength changes

The specific force produced in activated fibers stimulates receptor and membrane sensitivities to anabolic factors, including hormones

genetic potential

The upper limit of an individual's genetic potential dictates the absolute magnitude of the training adaptation.

testosterone in women

There are lower concentrations and little variation during the day

•Program design considerations for women

Upper body strength development • Women tend to have less upper body strength than men • Adding one or two upper body exercises or additional sets may be beneficial for women. • The high caloric cost of performing large muscle mass, multijoint, upper body lifts may aid in maintaining a healthy body composition.

•Ventilatory response to anaerobic exercise:

Ventilation generally does not limit resistance exercise and is either unaffected or only moderately improved by anaerobic training.

A direct result of the reduction in muscle mass is

a loss of muscular strength and power.

chronological age

actual age

large muscle group exercise using an adequate volume of total work results in

acute increased total testosterone concentrations in men

endocrine glands

body structures specialized for releasing hormones into the blood

physiological mechanisms that contribute to changes in peripheral blood concentrations of hormones with exercise

circadian pattern fluid volume shifts tissue pooling of blood venous pooling of blood hormone interactions with binding proteins

Overtraining syndrome can lead to

dramatic performance decreases in all athletes; the most common cause is intensified training without adequate recovery.

Growth cartilage in children is located at

epiphyseal plate, joint surface, and apophyseal insertions

steroid hormone

fat soluble and passively diffuse across cell membrane

short rest period types of workouts result in

greater serum concentrations compared to long rest protocol of similar work

Damage to the growth cartilage may

impair the growth and development of the affected bone

Downregulation

inability of a hormone to interact with a receptor

Resistance exercise protocols that use high volume, large muscle groups, and short rest periods result in

increased serum cortisol values.

testosterone effect on muscle tissue

increased strength and size of skeletal muscle, increased force production potential and muscle mass

size principle

motor units with larger and larger fibers are recruited as stimulus intensity increases

muscle hypertrophy

muscular enlargement from an increase in the cross-sectional area of the existing fibers.

Forces that reach or exceed a threshold stimulus initiate

new bone formation in the area experiencing the mechanical strain

What are hormones involved in?

protein synthesis and degradation mechanisms that are part of muscle adaptations to resistance exercise

categories of hormones

steroid, polypeptide, amine

Muscular Strength

the amount of force a muscle can produce with a single maximum effort

maximal oxygen uptake

the greatest amount of oxygen that can be used at the cellular level for the entire body

•Resistance training for female athletes

women can increase their strength at the same rate as men or faster

osteopenia

•A bone mineral density between −1 and −2.5 standard deviations (SD) of the young adult mean.

specific tendinous changes that contribute to size and strength increases:

•An increase in collagen fibril diameter •A greater number of covalent cross-links within the hypertrophied fiber •An increase in the number of collagen fibrils •An increase in the packing density of collagen fibrils

potential risks and concerns to youth resistance training

•Appropriately prescribed youth resistance training programs are relatively safe. •Forces placed on the joints during sport participation are greater and more difficult to anticipate than resistance training

sites where connective tissues can increase strength and load-bearing capacity:

•At the junctions between the tendon (and ligament) and bone surface •Within the body of the tendon or ligament •In the network of fascia within skeletal muscle

sex differences to Body size and composition

•Before puberty there are essentially no differences in height, weight, and body size between boys and girls. •Adult women tend to have more body fat and less muscle and bone than adult males. •Women tend to be lighter in total body weight than men. •

program design considerations for older adults

•Both aerobic exercise and resistance training are recognized as important components of a well-rounded fitness program for older adults. •Attention should be given to preexisting medical ailments, prior training history, and nutritional status before starting a resistance training program. •Volume and intensity should be altered throughout the year to prevent overtraining and ensure that progress is made.

Cardiovascular responses to Control of local circulation

•During aerobic exercise, blood flow to active muscles is considerably increased by the dilation of local arterioles. •At the same time, blood flow to other organ systems is reduced by constriction of the arterioles.

Gas responses in aerobic training

•During high-intensity aerobic exercise, the pressure gradients of oxygen and carbon dioxide cause the movement of gases across cell membranes. •The diffusing capacities of oxygen and carbon dioxide increase dramatically with exercise, which facilitates their exchange.

Cardiovascular responses to stroke volume

•End-diastolic volume is significantly increased. -Volume of blood available to be pumped by the left ventricle -Increased venous return •At onset of exercise, sympathetic stimulation increases stroke volume.

How can athletes stimulate connective tissue adaptations? Tendons, ligaments, fascia

•Exercise of low to moderate intensity does not markedly change the collagen content of connective tissue. •High-intensity loading results in a net growth of the involved connective tissues. •Forces should be exerted throughout the full range of motion of a joint.

Program design considerations for women. Anterior cruciate ligament injury

•Female athletes are up to six times more likely to incur an ACL injury than male players. •Joint laxity, ligament size, and neuromuscular deficiency leading to abnormal biomechanics may all be contributing factors. •Strength and conditioning professionals should ensure that females learn, and can repeatedly demonstrate, correct movement mechanics within a variety of environments.

cardiovascular responses to cardiac output

•From rest to steady-state aerobic exercise, cardiac output initially increases rapidly, then more gradually, and subsequently reaches a plateau. •With maximal exercise, cardiac output may increase to four times the resting level.

growth hormone responses in women

•Hormone concentrations and hormone responses to exercise vary with menstrual phase. •The mechanisms of this variation are unclear.

Sex differences to Strength and power output

•In terms of absolute strength, women generally have about two-thirds the strength of men. If comparisons are made relative to fat-free mass or muscle cross-sectional area, differences in strength between men and women tend to disappear

cross education

•Increased strength and neural activity in the contralateral resting muscle. -central nervous adaptation

oxygen uptake

•Increases during an acute bout of aerobic exercise •Is directly related to the mass of exercising muscle, metabolic efficiency, and exercise intensity

Preadolescents have more potential for an increase in strength owing to neural factors

•Increases in motor unit activation and synchronization •Enhanced motor unit recruitment and firing frequency •Improvements in motor skill performance •Coordination of the involved muscle groups

exercise responses of Insulin-like growth factors

•Insulin-like growth factor I (IGF-I) is most studied because of its role in protein anabolism. •Exercise results in acute increases in blood levels of IGF-I.

female athlete triad

•Interrelationships between energy availability, menstrual function, and bone mineral density •Caused by high training volumes or intensities with inadequate dietary intake •Increases the risk for osteoporosis and amenorrhea (the absence of a menstrual cycle for more than three months) •

Exercise variables that can increase serum testosterone concentrations

•Large muscle group exercises (deadlift, squats) •Heavy resistance (85-95% of 1RM) •Moderate to high volume of exercises •Short rest intervals (30 seconds to 1 minute) Two years or more of resistance training experience

during and after puberty training induced gains in strength are typically associated with gains in muscle hypertrophy

•Males - Increase in testosterone •Females - Increase in growth hormone and insulin-like growth factor

youth responsiveness to resistance training

•Strength gains of roughly 30% to 40% are typically observed in untrained preadolescent children following short-term (8-20 week) resistance training programs. •Data suggest that training-induced strength gains in children are impermanent and tend to return to untrained control group values during the detraining period. -Importance of continuous training to maintain the strength advantage of exercise induced adaptations -Changes in neuromuscular functioning are at least partly responsible

Cardiovascular responses to Blood pressure

•Systolic blood pressure estimates the pressure exerted against the arterial walls as blood is forcefully ejected during ventricular contraction. -Increases with aerobic exercise •Diastolic blood pressure is used to estimate the pressure exerted against the arterial walls when no blood is being forcefully ejected through the vessels. -Indication of peripheral resistance -Can decrease with aerobic exercise due to vasodilation •

cardiac output (or Q)

•The amount of blood pumped by the heart in liters per minute (SV × HR).

How can athletes stimulate connective tissue adaptations? cartilage

•Weight-bearing forces and complete movement throughout the range of motion seem to be essential to maintaining tissue viability. •Moderate aerobic exercise seems adequate for increasing cartilage thickness. •Strenuous exercise does not appear to cause degenerative joint disease.

testosterone responses in women

•Women have about 15- to 20-fold lower concentrations of circulating testosterone than men do. The testosterone concentration can vary substantially between individual women, as some women secrete higher concentrations of adrenal androgens

One of the most commonly measured adaptations to aerobic endurance training is

•an increase in maximal oxygen uptake associated with an increase in maximal cardiac output.

puberty

•period of time in which secondary sex characteristics develop and a child is transformed into a young adult. •During puberty, changes also occur in body composition and the performance of physical skills.