Presentation on theme: "Preadolescent Youth Refers to a period of time before the development of secondary sex characteristics and corresponds to ages: 6-11 in girls 6-13 in boys."— Presentation transcript:
1 Age and Sex Related Differences and Their Implications for Resistance Exercise
2 Preadolescent YouthRefers to a period of time before the development of secondary sex characteristics and corresponds to ages:6-11 in girls6-13 in boys
3 Chronological Age vs. Biological Age age in months and yearsBiological Age:skeletal age, physical maturity, or sexual maturationChildren do not grow at a constant rateIndividualize training based on the child’s maturity level, training age (length of time resistance training), and needs
4 Peak Height Velocity Peak Height Velocity Pubertal growth spurt About age 12 in females and age 14 in malesThere is weakness in the bonesMuscle imbalance between flexor and extensor groups around a jointBone growth is faster than the muscle tendon unit
5 Pubertal Growth SpurtDuring pubertal growth spurts personal trainer’s need to emphasize the following:FlexibilityCorrect muscle imbalancesDecrease volume and intensity of R.T.Risk Factors:overuse injuriesgrowing pain complaints (growing pains don't hurt around the bones or joints only in the muscles)
6 Pubertal Growth SpurtAs a trainer, if a young athlete complains of pain or discomfort during a growth spurt, you should be suspicious of an overuse injury rather than labeling the complaints as “growing pains”
7 Muscle and Bone Growth Peak muscle mass occurs between the ages of: 16-20 in females18-25 in males
8 Bone GrowthBone formation occurs in the diaphysis which is the central shaft of a long bone and in the growth cartilage
9 Bone Growth Growth cartilage is located at three sites in children: Epiphyseal plateJoint surfaceApophyseal insertions of muscle tendon units
10 Bone GrowthDamage to the growth cartilage may impair the growth and development of the affected bone
11 Children The Growing Child Muscle and Bone Growth Muscle mass steadily increases throughout the developing years.During puberty, a 10-fold increase in testosterone production in boys results 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.
12 Muscular Strength and Adolescence Muscle mass increases first then strengthThe development of the nervous system is related to the expression of muscular strengthPrimarily the development of the myelin sheathWhy?
13 If Myelination of Nerve Fibers is Absent or Incomplete Fast reactions and skilled movements cannot be successfully performedHigh levels of strength and power are impossible
14 Muscular Strength and Adolescence The myelination of motor nerves is incomplete until sexual maturationAs the nervous system develops, children improve their performance in skills that require balance, agility, strength, and power.Personal Trainers should not expect children to respond to training in the same way as adults until they reach neural maturity
15 Muscular Strength and Adolescence Physiological functions are more closely related to biological age than chronological ageWhat that means is that early-maturing children will probably have an advantage when it comes to measures of absolute strength when compared to later-maturing children of the same sexNervous system development is incomplete until sexual maturation
16 Muscular Strength and Adolescence 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.
17 Body Types Mesomorph muscular and broader shoulders Endomorph rounder and broader hipsEctomorphslender and tall
18 Recommendations for Personal Trainers Who Train Children Prior to participation, adolescents should be evaluated by a physician.Parents should be educated about the benefits and risks of physical activity.Parents should understand the importance of physical activity.Children and adolescents should be encouraged to participate in year-round physical activity.
19 Recommendations for Personal Trainers Who Train Children Provide close supervisionSpeak to children in a manner they can understandDesign activities that ensure enjoymentOffer a variety of exercises and avoid regimentation
20 Program Design Considerations for Children There is no minimal age requirement for R.T. in childrenAll children should be screened for any injury or illnessThere is no scientific evidence to suggest that supervised and well designed youth resistance training programs stunts growth of children
21 Program Design for Children Personal trainer’s should not expect children to exercise in the same manner as adultsIt is not recommended that children perform 30 minutes of continuous exercise with a predetermined THRR because prolonged activity will decrease their motivation to exercise
22 Program Design Considerations for Children Each child should understand the benefits and risks associated with resistance training.Competent and caring fitness professionals should supervise training sessions.The exercise environment should be safe and free of hazards.All equipment should be in good repair and properly sized to fit each child.Dynamic warm-up exercises should be performed before resistance training.
23 Program Design Considerations for Children 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%) as strength improves.Children should be encouraged to drink plenty of water before, during, and after exercise
24 Program Design Considerations for Children Children should be encouraged to drink plenty of water before, during, and after exerciseRegular participation in R.T. along with a calcium rich diet maximizes bone densityIt is better to underestimate than overestimate children’s abilities
25 Program Design for Children FrequencyDaily. Frequent activity sessions three or more each dayIntensityModerate to vigorous. Alternating bouts of activity with rest periodsDurationIt is recommended that children expend 6-8 cal/kg/day equal to a caloric expenditure of 60 minutes or more of active playExample:A girl who weighs 88 pounds (44 kg) should expend 264 calories per day ( 44 kg x 6 cal)
26 R.T. Program Design for Children Supervision and Instruction5-10 minute warm-up1-3 sets of 6-15 reps on multijoint and single joint exercisesIntensity should be increased gradually as strength improves (5-10%)2-3 nonconsecutive training sessions per week is recommended
27 R.T. Program Design for Children Advanced multijoint exercises (clean and jerk, snatch) can be used but the focus must be on appropriate loads and proper form
28 Program Design for Children Example of a Personal Training SessionCircuit of 8-12 stations that include:Jumping ropeJumping jacksPush-up’sBody weight squatsMedicine ball tossesBalancing drillsShuttle runsCone drills
29 Older AdultsOften debated, but a person over the age of 65 is defined as an older adultVarious medical conditions are common among older adultsHeart diseaseCancerDiabetesDepressionObesityLow back painFrailty
30 Older Adults 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.
31 Bone LossBone becomes fragile with age because of a decrease in bone mineral densityEveryday activities may cause bone fractures (especially hip, spine and wrist)
32 Osteopenia and Osteoporosis bone density at the spine or hip between -1.0 and -2.5 standard deviations below the average for healthy young adults can be a precursor to osteoporosisOsteoporosis:a disease in which the bones become extremely porous, are subject to fracture, and heal slowly, occurring especially in women following menopause and often leading to curvature of the spine from vertebral collapse.
34 Muscle Loss (Atrophy) Sarcopenia: decreased muscle mass Adults lose about one-half pound (.2 kg) of muscle per year in their 30’s and 40’sAdults 50 and older lose about 1 pound of muscle per yearThe average aging American adds 10 pounds of body weight each decade of adult lifeLoss of muscle may be responsible for fat gain
35 Causes of Bone and Muscle Loss Lack of regular physical activityChange in protein metabolismEndocrine system changes (hormones)Loss of neuromuscular functionAltered genetic expressionApoptosis (cell death)Inadequate nutrition
36 Resistance Training and Sarcopenia Recent studies show that resistance training improves the balance of protein within the muscle, allowing more muscle protein synthesis than breakdown, allowing muscle maintenance or even hypertrophy. Chronic resistance training increases both muscle protein synthesis and breakdown, but synthesis at a greater magnitude. This creates a positive protein balance, restoring protein in those who’ve lost mass as well as preventing muscle mass loss in those not already sarcopenic.
37 Resistance Training and Sarcopenia Exercise enhances insulin sensitivity, which stimulates protein synthesis, contributing to the positive protein balance.Protein building cells called satellite cells aid in muscle repair and hypertrophy increase in response to resistance training.
38 Lack of Physical Activity and Sarcopenia Lack of physical activity, especially resistive training, allows the balance of protein synthesis with breakdown to become negative, breakdown outrunning synthesis. If more protein is destroyed than manufactured in the muscle, muscle wasting occurs.Low muscle mass before old age predisposes one to sarcopenia. The more lean muscle mass one has to begin with, the more one can afford to lose before becoming sarcopenic.
39 Age Related Changes Female age: 20 30 40 50 BW 126 136 146 156 Muscle Weight4535Fat Weight29445974Percent Fat233247
40 Health Benefits of Older Adult Exercise Aerobic endurance exercise such as walking, cycling, and jogging is effective for:Increasing calorie utilizationReducing body weightLessening the risk of high blood pressureImproving sleepImproving digestionReduces the risk of osteoporosis
41 Benefits of Resistance Training in Older Adults Lowers the risk of cardiovascular diseaseDecreases resting blood pressureTwo months of R.T. may reduce blood pressure by up to 7 mm HgImproves cholesterolReduces the risk of colon cancer (running and R.T. have been shown to speed up Gastrointestinal emptying)
42 Benefits of Resistance Training in Older Adults Lowers the risk of type II diabetesImproves insulin response and glucose utilization by the cellsReduces low back painMay improve joint functionEases the pain of arthritis
43 Benefits of Resistance Training in Older Adults Maintain muscle tissueR.T. is the only type of exercise that can maintain muscle and metabolism as people age
45 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.
46 What Are the Safety Recommendations for Resistance Training for Seniors? Avoid performing the Valsalva maneuver.Allow 48 to 72 hours of recovery between exercise sessions.Perform all exercises within a range of motion that is pain free.Receive exercise instruction from qualified personal trainers.
47 R.T. Guidelines for Older Adults Frequency2-3 nonconsecutive sessions per weekRecovery48-72 hoursIntensity40-80% of maximumRepetition6-12 repsSets1-3
48 Aerobic Endurance Guidelines for Older Adults Frequency2-5 times per weekDuration20-60 minutes per sessionIntensity60-90% of MHR (75% of MHR is recommended)Maximal heart rate decreases with age (10 beats per decade)Taking beta-blockers (heart medications) lowers maximum heart rateMonitor exercise by heart rate, RPE scale or talk test
49 Resistance Training for Females Men and women respond to R.T. in similar waysWomen can increase their strength at the same rateAbsolute gains in strength (amount of weight lifted) are greater in malesHigh volume and high intensity training will lead to hypertrophy
50 Resistance Training for Females In terms of strength, females have about two thirds the strength of menLower body strength is closer to male valuesUpper body strength is generally weaker often due to broad shoulders in males
51 Resistance Training for Females R.T. programs for females can be the same as malesTraining should incorporate upper body strength (push-up, pull-up…)
52 Knee Injuries in Female Athletes Studies report that female college aged basketball players are 6 times more likely to incur an ACL tear than male playersHow Can Female Athletes Reduce Their Risk of Injury?Begin with a preparticipation screening by a sports medicine physician.Participate in a year-round conditioning program that includes resistance training, plyometric training, agility training, and flexibility training.
53 Knee Injuries in Female Athletes Every exercise session should be preceded by a general dynamic warm-up and a specific warm-up using movements that resemble those involved in the activity.Athletes should wear appropriate clothing and footwear during practice and games.Athletes should be encouraged to maximize their athletic potential by optimizing their dietary intake.