ArticlePDF Available

Resistance training for kids: Right from the Start

September 2016
ACSMʼs Health & Fitness Journal 20(5):16-22

DOI:10.1249/FIT.0000000000000236

Authors:

Avery Faigenbaum

The College of New Jersey

James Mcfarland

Hillsborough Township Public Schools

Learning Objectives 1. Understand the importance of enhancing muscular fitness early in life. 2. Dispel the myths associated with youth resistance training. 3. Describe the PROCESS [Progression, Regularity, Overload, Creativity, Enjoyment, Socialization, and Supervision] of developing a youth resistance training program.

Content uploaded by James Mcfarland

Content may be subject to copyright.

RESISTANCE TRAINING FOR KIDS

Right from the Start

by Avery D. Faigenbaum, Ed.D., CSCS, FACSM and James E. McFarland, Ed.M., CSCS

Learning Objectives

1. Understand the importance of

enhancing muscular fitness

early in life.

2. Dispel the myths associated

with youth resistance training.

3. Describe the PROCESS [Pro-

gression, Regularity, Overload,

Creativity, Enjoyment, Socializa-

tion, and Supervision] of develop-

ing a youth resistance training

program.

Key words: Children, Motor Skills,

Strength Training, Physical

Development, Youth Fitness

Global recommendations on youth physical activity suggest that children

and adolescents should accumulate at least 60 minutes of moderate to

vigorous physical activity (MVPA) daily in the context of family, school,

and community activities (33). In addition to active games and aerobic

exercise, regular participation in strength-building activities also should

be incorporated into the weekly routine of school-aged youth (21,33). Despite traditional

fears and misinformed concerns associated with youth resistance training, a compelling

body of evidence has found that participation in a supervised resistance training program

can be a safe, effective, and worthwhile method of conditioning for children and adoles-

cents (5,14,21). Nowadays, a growing number of fitness centers and sport training clubs

offer youth fitness programs that include various forms of resistance exercise.

Many of the benefits associated with adult resistance training programs are attainable

by children and adolescents (21,29). However, youth resistance training programs should

be supervised by qualified fitness professionals and consistent with the needs, interests,

and abilities of younger populations. This is where the art of youth resistance training

comes into play because the physical demands of training need to be balanced with ef-

fective instructional strategies that maximize enjoyment, foster socialization, and spark

an ongoing interest in daily MVPA. That is, the most effective youth fitness professionals

are able to use different pedagogical approaches to address individual learning styles

and developmental needs. Notwithstanding the importance of improving muscular fit-

ness (i.e., muscular strength, muscular power, and muscular endurance), youth fitness

professionals should provide an opportunity for all participants to have fun, make

friends, and learn something new.

In this article, a review of troubling trends in muscular fitness among modern-day

youth will highlight the need for planned resistance training early in life. Myths associated

with youth resistance training will be addressed and the potential benefits of integrating

strength-building exercises into youth fitness programs will be discussed. Ideas for enhanc-

ing resistance training skill competency will provide fitness professionals with information

that can be used to design training programs that are safe, effective, and progressive. For

Photo courtesy of Avery D. Faigenbaum.

16 ACSM’sHealth & Fitness Journal

September/October 2016

ease of discussion, the terms youth and young athletes refer to both

children and adolescents.

TROUBLING TRENDS IN MUSCULAR FITNESS

Although the enduring impact of daily MVPA on the health and

well-being of youth continues to be advanced in the literature

(33), these benefits will be realized only if youth have developed

adequate levels of muscular fitness and movement skill compe-

tency (4,6,16). A certain level of force production and force at-

tenuation is needed to perform movement skills, and therefore,

the importance of enhancing muscular fitness should be consid-

ered foundational to long-term physical development (12,20).

Youth who do not become proficient movers early in life will be

less likely to participate in diverse physical activities as adults

(27,30). This idea relates to Seefeldt’soriginalnotionofaprofi-

ciency barrier whereby children who do not surpass a critical

threshold of motor skill proficiency early in life will be less likely

to engage in sports and physical activities later in life (28). Just

like the skills of reading and writing, interest and aptitude in

physical activity should begin early in life with a strong focus

on movement skills and physical abilities.

Epidemiological findings from an international sample of

children indicate that a growing number of youth are not meet-

ing physical activity recommendations (31), and those with

lower levels of MVPA are at increased risk of obesity (18). With-

out opportunities to develop the prerequisite levels of muscular

fitness and motor skill proficiency early in life, youth are less

likely to participate in games and activities with confidence

and vigor later in life (16,22). Secular trends in measures of mus-

cular fitness in English children indicate declines in bent arm

hang, sit-up performance, and hand grip strength during a

10-year period (7). Similar observations were reported in se-

lected measures of muscular power (e.g., long jump and vertical

jump) in Spanish adolescents (23) and fundamental movement

skills (e.g., jumping and kicking) in Australian youth (17). Al-

though many factors influence time spent in MVPA during

the growing years (18), the global pandemic of physical inactivity

may be due, at least in part, to a deficiency of muscular fitness

and motor skill performance in modern-day youth.

In support of this view a 2-year study of children between 6

and 10 years ofage found that those with low motorcompetency

participated less in sports and had fewer opportunities for devel-

oping motor abilities and physical fitness (16). Other re-

searchers noted an increasingly widening gap in gross motor

coordination between normal-weight and overweight children

(10). Unfortunately, the divergence in performance between

children with low and high levels of muscular fitness seems

to persist across developmental time in the absence of targeted

interventions. Without regular opportunities to enhance their

muscular strength and motor skill abilities early in life, youth will

be less likely to engage in the recommended amount of daily

MVPA and more likely to experience negative health outcomes

(12). Of note, recent increases in the waist circumference of ad-

olescents during periods of bodyweight stabilization suggest that

modern-day youth have more fat and less muscle than previous

generations (15).

TRAIN THE DEVELOPING BRAIN

The first few years of life are characterized by rapid changes in

the myelination of the central nervous system, and the effects of

a well-designed resistance training program can be long lasting

(24). Similar to learning a new language or playing a musical in-

strument, there is a unique opportunity to target strength devel-

opment early in life to set the stage for greater gains in physical

fitness later in life. Research findings indicate that children show

greater training-induced gains in various motor performance

skills (e.g., jumping, running, and throwing) after resistance train-

ing than adolescents (4). Furthermore, training programs that

target sports-related injuries to the anterior cruciate ligament are

more effective if they start earlier in life before the onset of neuro-

muscular deficits that may increase injury risk (25). Collectively,

these observations underscore a potential synergist adaptation

whereby participation in strength-building activities early in life

compliments naturally occurring changes in muscular fitness (11).

New insights into the design of long-term physical develop-

ment programs have highlighted the importance of enhancing

muscular strength during childhood and continuing participa-

tion in resistance training activities throughout adolescence

(12,20,21). Indeed, resistance training should be a priority in

youth fitness programs because muscular strength is the driving

force toward performance enhancement and injury prevention

(11,21). Although the need for individualization should not be

overlooked when designing programs for youth of different

sex, maturity status, and training experience, the formation of

a long-term plan that maximizes strength development is critical

for the promotion of daily physical activity as an ongoing life-

style choice. As such, the concept of long-term physical devel-

opment should be viewed as a structured, progressive, and

informed approach for enhancing health, fitness, and perfor-

mance in children and adolescents (20).

Years ago, some observers had concerns that resistance train-

ing would be unsafe or ineffective for youth (see side bar). How-

ever, a compelling body of research indicates that a systematic

approach to long-term physical development grounded in resis-

tance training offers observable health and fitness value to chil-

dren and adolescents (21,29). In addition to enhancing muscular

fitness and motor skill performance, various forms of resistance

training can increase bone mineral density, improve cardiovas-

cular risk factors, facilitate weight control, and prepare inactive

youth for the demands of physical activity and sport (11,21,29).

The American College of Sports Medicine suggests that in the

early stages of an exercise program, muscle-strengthening exer-

cises may need to precede aerobic training activities in frail se-

niors (1). In the same light, targeted interventions that include

strength-building exercises and directed-movement practice

may be needed to activate inactive youth right from the start.

Volume 20 | Number 5 www.acsm-healthfitness.org 17

LEARN TO MOVE

Education and instruction on proper resistance training tech-

niques and procedures should begin early in life to optimize

training adaptations and spark an ongoing interest in resistance

exercise. Although there is no minimum age for participation in

a supervised resistance training program, most healthy 7- and

8-year-olds are ready to follow instructions and adhere to safety

rules (11). Well-designed resistance training programs provide a

needed opportunity for boys and girls toenhance their muscular

fitness while improving their resistance training skill competency

(RTSC). The construct of RTSC refers to the technical ability of

performing a resistance exercise and involves the evaluation of

movement patterns that are considered essential for the mastery

of a particular exercise (2). Notwithstanding the importance of

prescribing the right dose (i.e., intensity and volume) of resistance

training, it is equally important to provide meaningful feedback

on the quality of the exercise performance. Consequently, RTSC

relates to one’s physical development as well as one’sabilityto

focus, follow instructions, and execute a task properly.

To improve RTSC, fitness professionals should provide con-

sistent feedback on the technical performance of every exercise.

Because most youth have limited experience in resistance train-

ing, the importance of assessing exercise technique using accepted

commonalities of resistance exercise performance should not be

overlooked. The perception of RTSC as opposed to the amount

of weight lifted may help to reinforce the importance of main-

taining proper exercise technique and illustrates the significance

of movement pattern efficiency as the criterion measure (13). In

addition, by assessing performance and recording component

scores, fitness professionals can identify skills that need more in-

structional time, and youth can monitor their own progress as

they work toward clearly defined goals.

An example of an RTSC checklist for the back squat exercise

is outlined in the Table. During training sessions, youth are

given specific feedback related to their technical performance

and general demeanor. Consequently, they become aware of

their strengths and weaknesses and address areas in need of im-

provement. The four levels used to assess RTSC performance

are advanced (3 points), basic (2 points), capable (1 point), and

developing (0 point). The advanced level is indicative of skilled

lifting performance and a genuine interest in improving per-

sonal fitness. The developing level indicates that the participant

performed a skill improperly or displayed behavior that was

disrespectful or uncooperative. By recording the component

scores and tallying up the total points for all phases of a spe-

cific exercise, fitness professionals can identify skills that need

Sidebar: Myths That Won’tQuit

Myth: Resistance training will stunt the growth of children

No scientific evidence indicatesthat participation in a supervised resistance training program will stunt the growth of children or damage

developing growth plates (21). Childhood may actually be the opportune time to engage in weight-bearing activities that enhance bone

mineral content and density (3). In all likelihood, regular participation in a well-designed resistance training program during the growing

years will have a favorable influence on bone growth and development.

Myth: Resistance training is unsafe for children

The risks associated with youth resistance training are not greater than other recreational and sport activities in which youth regularly

participate (14,21). Although accidents can happen, the key is to provide qualified instruction in a safe training environment and sensibly

progress the program based on resistance training skill competency. In addition, basic education on weight training room etiquette, in-

dividual goals, and realistic outcomes should be part of youth resistance training programs.

Myth: Youth need to be at least 12 years old to life weights

Although there is no evidence-based minimum age for participation in a youth resistance training program, all participants should be

able to accept directions and follow safety rules. Boys and girls younger than 12 years old have participated safely in supervised resis-

tance training programs (14). Generally, when youth are ready for sport participation, approximately ages 7 or 8, they are ready for some

type of resistance training as part of a well-rounded fitness program.

Myth: Girls will develop bulky muscles if they lift weights

Training-induced gains in muscular strength during childhood are primarily due to neuromuscular adaptations and skill develop-

ment. Although boys may develop bigger muscles during the growing years because the effects of anabolic hormones would be op-

erant, girls can get stronger throughout childhood and adolescence while gaining all the benefits from resistance training without

developing bulky muscles (21).

Myth: Resistance training is only for young athletes

Regular participation in a well-designed resistance training program offers observable health and fitness value for all children and ado-

lescents (21). In addition to performance enhancement and injury reduction, resistance training can improve musculoskeletal health,

enhance metabolic function, and increase daily physical activity. Resistance training may be particularly beneficial for overweight youth

who often are unwilling and unable to perform prolonged periods of aerobic exercise (29).

RESISTANCE TRAINING FOR KIDS

18 ACSM’sHealth & Fitness Journal

September/October 2016

more instructional time and effort. The back squat RTSC check-

list can be used as a framework for developing rubrics for

other exercises.

The ability to perform multijoint resistance exercises with

proper technique requires adequate levels of muscular strength

along with the coordinated integration of different physical,

emotional, and cognitive abilities that evolve during the growing

years (24). With regular exposure to resistance training early in

life, children will have an opportunity to enhance their RTSC

and muscular strength on a variety of exercises. Although youth

with poor muscular strength and low RTSC may have difficulty

performing basic resistance exercises, those with higher levels of

muscular strength and skill competency will be better prepared

to learn more advanced skills because they can use developing

pathways that influence motor control and movement profi-

ciency (11,24).

If qualified fitness professionals assess movement mechanics

and provide constructive feedback during training sessions,

youth will have a unique opportunity to learn task-related activ-

ities and enhance their RTSC. If participants are beginners (low

muscle strength and low RTSC), fitness professionals should

prescribe a range of basic resistance exercises (e.g., squatting,

pushing, or pulling movements) that enhance muscular strength

while improving one’s competence to perform a variety of exer-

cises. As youth gain competence and confidence in their ability

to perform basic exercises, their capacity for resistance exercise

can be improved with more advanced training programs

(Figure 1). For technically competent youth with high levels of

muscular strength, more advanced programs will be needed to

optimize training adaptations (11,19). An example of a youth re-

sistance training program with exercise progressions will be pro-

vided in a future issue of ACSM’s Health & Fitness Journal

UNDERSTAND THE PROCESS

Youth resistance training programs need to be evidence-based

and carefully prescribed to optimize training outcomes,

TABLE: Back Squat Resistance Training Skill Competency Checklist

Phase Desired Action Common Breakdown

Points*

Max Earned

Check point 1. Safe exercise area Inadequate space 3

2. Correct starting weight Incorrect weight selection

3. Collars on bar (if plates are used), and well-positioned

safety rails

Lack of collars & poorly positioned

safety rails

Ready position 4. Bar on shoulders and upper back Bar positioned on neck 3

5. Head neutral & eyes forward Head facing downward

6. Feet wider than shoulder width Feet position too narrow

Downward phase 7. Flex hips and knees Thighs not at proper depth 3

8. Thighs parallel to floor Trunk begins to flex forward

9. Elbows under bar, knees over feet & behind toes,

torso erect, and feet flat

Knees inward or forward

Heels rise

Upward phase 10. Extend hips and knees Trunk begins to round forward 3

11. Torso upright, elbows under bar, knees over feet

& behind toes

Elbows drift behind bar, knees move

inward/forward

12. Maintain bar control with firm grip until bar is racked Firm grip is not maintained

General demeanor 13. Responsibility Does not follow safety rules 3

14. Resourcefulness Unwilling to solve simple problems

15. Respect Does not cooperate with others

Tota l Po int s 15

The back squat resistance training skill competency checklist can be used to assess exercise performance and communicate the specific actions and behaviors that are

required for this exercise.

*3 points, advanced; 2 points, basic; 1 point, capable; and 0 point, developing.

Volume 20 | Number 5 www.acsm-healthfitness.org 19

maximize exercise adherence, and reduce the risk of unto-

ward events. Although factors such as heredity, training expe-

rience, and health habits (e.g., nutrition and sleep) will

influence the rate and magnitude of adaptation that occurs,

seven fundamental principles that determine the effectiveness

of youth resistance training programs are the principles of

(a) the Progression, (b) Regularity, (c) Overload, (d) Creativity,

(e) Enjoyment, (f) Socialization, and (g) Supervision. These basic

principles can be remembered as the PROCESS of youth resis-

tance training. Although the principles of progression, regularity,

and overload are well-established tenets of resistance training (26),

the concepts of creativity, enjoyment, socialization, and super-

vision are particularly applicable to the design of sustainable

youth fitness programs. When working with children and ado-

lescents, it is important to remember that the goal of the program

should not be limited to increasing muscular strength. Improving

motor skills, fostering new social networks, and promoting healthy

behaviors in a supportive environment are equally important.

This is where the art and science of youth resistance training

come into play because the principles of pediatric exercise

science need to be balanced with effective teaching and ongoing

instruction that is developmentally appropriate for children

and adolescents.

Principle of Progression

The principle of progression refers to the fact that the demands

placed on the growing body must be increased gradually

through time to achieve long-term gains in muscular fitness.

This does not mean that heavier weights should be used every

workout, but rather, that through time, the stress placed on

the body should progressively become more challenging to con-

tinually stimulate adaptations and maintain interest in the pro-

gram. Without a more challenging stimulus that is consistent

with each individual’s needs and abilities, additional training-

induced adaptations are unlikely. Although increasing the train-

ing load or performing additional sets are common methods of

progression, performing novel exercises or more complex move-

ment patters also are beneficial.

Principle of Regularity

Although the optimal resistance training frequency may depend

on each participant’s training goals, two to three training ses-

sions per week on nonconsecutive days are reasonable for most

youth (21). Inconsistent training will result in only modest train-

ing adaptations, and periods of inactivity will result in a loss

of muscular strength and power. The adage “use it or lose it”

is appropriate for resistance exercise because training-induced

adaptations in muscular fitness cannot be stored. The principle

of regularity states that long-term gains in physical development

will be realized only if the program is performed on a consistent

basis throughout childhood and adolescence.

Principle of Overload

The overload principle is a fundamental tenet of all resistance

training programs. The overload principle simply states that to

enhance muscular fitness, the body must exercise at a level be-

yond that at which itis normally stressed. Otherwise, if the train-

ing stimulus is not increased beyond the level to which the

muscles are accustomed, the participant will not maximize

Figure 1. Youth resistance training guidelines with progression based on each participant's resistance training skill

competency and muscular strength.

Photo courtesy of Avery D. Faigenbaum.

RESISTANCE TRAINING FOR KIDS

20 ACSM’sHealth & Fitness Journal

September/October 2016

training adaptations. Training overload can be manipulated by

changing the intensity, volume, frequency, or choice of exercise.

Principle of Creativity

The creativity principle refers to the imagination and ingenuity

that can help to optimize training-induced adaptations and en-

hance exercise adherence. By sensibly incorporating novel exer-

cises and new training equipment into the program, fitness

professionals can help youth overcome barriers and maintain in-

terest in resistance exercise. Creative thinking is particularly

valuable when designing resistance training programs for youth

with special needs or those with high levels of RTSC. The fun-

damental principles related to the prescription of sets and repe-

titions should be balanced with imagination and creativity. For

example, youth can create new resistance exercises with light-

weight medicine balls or find a solution on their own to a chal-

lenging task that requires balance and coordination.

Principle of Enjoyment

Enjoyment is an important determinant of participation in

youth fitness and sport programs (32). The principle of enjoy-

ment states that participants who enjoy the experience of partic-

ipating in exercise or sports activities are more likely to adhere to

the program and achieve training goals. Although encourage-

ment from fitness professionals and support from family and

friends can influence exercise adherence, the enjoyment a child

feels during and after an exercise session can facilitate the sus-

tainability of the desired behavior. Enjoyment can be defined as

a balance between skill and challenge (9). If the resistance train-

ing program is too advanced, youth may become anxious and

lose interest. Conversely, if the training program is too easy, then

youth may become bored. Youth resistance training programs

should be matched with the physical abilities of the participants

for the training experience to be enjoyable.

Principle of Socialization

Participation in a resistance training program can help youth in-

teract with others in a positive and supportive manner. The

principle of socialization states that gains in muscular fitness will

be optimized if participants make new friends, meet other peo-

ple, and work together toward a common goal. Participating

in a resistance training program can help youth feel connected to

other participants as they gain confidence and competence in

their physical abilities and work toward a common goal. By pay-

ing more attention to the importance of socialization, fitness

professionals will likely boost participants’exercise performance

and enjoyment of the training experience.

Principle of Supervision

The principle of supervision states that the safety and efficacy of

exercise programs are maximized when qualified fitness profes-

sionals supervise activities and provide meaningful feedback

throughout the training session. Not only does supervised resis-

tance training reduce the risk of injury, but youth who partici-

pate in supervised resistance training programs are likely to

make greater gains in muscular fitness (8). Indeed, qualified su-

pervision is a critical component of any youth resistance training

program, particularly for beginners who need to develop com-

petence on basic exercises before progressing to more complex

movements. Youth fitness specialists should be well versed in the

principles of pediatric exercise science and should know how

to teach, progress, and modify skill-based exercises (Figure 2).

SUMMARY

Troubling trends in muscular fitness among modern-day youth

have created an immediate need to implement safe, effective,

and enjoyable resistance training programs for children and

adolescents. New insights into the design of long-term physical

development programs have highlighted the importance of en-

hancing muscular fitness and resistance training skill compe-

tency early in life to set the stage for more advanced training

later in life. Fitness professionals who genuinely appreciate the

uniqueness of younger populations and who understand the

PROCESS of youth resistance training are best prepared to de-

sign, supervise, and instruct sustainable programs that spark an

ongoing interest in health and fitness.

1. American College of Sports Medicine. ACSM’s Guidelines for Exercise Testing and

Prescription. Baltimore (MD): Lippincott, Williams and Wilkins; 2013.

2. Barnett L, Reynolds J, Faigenbaum A, Smith J, Harries S, Lubans D. Rater

agreement of a test battery designed to assess adolescents’resistance training

skill competency. J Sci Med Sport. 2015;18(1):72–6.

3. Behringer M, Gruetzner S, McCourt M, Mester J. Effects of weight-bearing

activities on bone mineral content and density in children and adolescents: a

meta-analysis. J Bone Miner Res. 2014;29(2):467–78.

4. Behringer M, Vom Heede A, Matthews M, Mester J. Effects of strength training on

motor performance skills in children and adolescents: a meta-analysis. Pediatr

Exerc Sci. 2011;23(2):186–206.

5. Behringer M, Vom Heede A, Yue Z, Mester J. Effects of resistance training in

childrenand adolescents: a meta-analysis.Pediatrics. 2010;126(5) :e1199–210.

6. Cattuzzo M, Dos Santos HR, Ré A, et al. Motor competence and health related

physical fitness in youth: a systematic review. JSciMedSport. 2016;19(2):123–9.

Figure 2. Youth fitness professionals are most important in

terms of education, motivation, socialization, and gratification.

Photo courtesy of Avery Faigenbaum.

Volume 20 | Number 5 www.acsm-healthfitness.org 21

7. Cohen DD, Voss C, Taylor MJ, Delextrat A, Ogunleye AA, Sandercock GR. Ten-year

secular changes in muscular fitness in English children. Acta Paediatr.2011;

100(10):e175–7.

8. Coutts AJ, Murphy AJ, Dascombe BJ. Effect of direct supervision of a strength

coach on measures of muscular strength and power in young rugby league

players. JStrengthCondRes. 2004;18(2):316–23.

9. Csikszentmihalyi M, Abuhamdeh S, Nakamura J. Flow. In: Elliot A, editor. Handbook

of Competence and Motivation. New York (NY): The Guilford Press; 2005. p. 598–698.

10. D’Hondt E, Deforche B, Gentier I, et al. A longitudinal analysis of gross motor

coordination in overweight and obese children versus normal-weight peers.

Int J Obes (Lond). 2013;37(1):61–7.

11. Faigenbaum AD, Lloyd RS, MacDonald J, Myer GD. Citius, Altius, Fortius:

beneficial effects of resistance training for young athletes: narrative review.

Br J Sports Med. 2016;50(1):3–7.

12. Faigenbaum AD, Lloyd RS, Myer GD. Youth resistance training: past practices,

new perspectives and future directions. Pediatr Exerc Sci. 2013;25(4):591–604.

13. Faigenbaum AD, McFarland JE. Criterion repetition maximum testing. Strength

Cond J. 2014;36(1):88–91.

14. Faigenbaum A, Myer G. Resistance training among young athletes: safety,

efficacy and injury prevention effects. Br J Sports Med. 2010;44(1):56–63.

15. Fernández JR, Bohan Brown M, López-Alarcón M, et al. Changes in pedia tric waist

circumference percentiles despite reported pediatric weight stabilization in the

United States. Pediatr Obes. 2016. [Epub ahead of print].

16. Fransen J, Deprez D, Pion J, et al. Changes in physical fitness and sports

participation among children with different levels of motor competence: a 2-year

longitudinal study. Pediatr Exerc Sci. 2014;26(1):1–21.

17. Hardy L, Barnett L, Espinel P, OkelyA. Thirteen-year trends in childand adolescent

fundamental movement skills: 1997-2010. Med Sci Sports Exerc. 2013;45(10):

1965–70.

18. Katzmarzyk P, Barreira T, Broyles S, et al. Physical activity, sedentary time, and

obesity in an international sample of children. Med Sci Sports Exerc. 2015;

47(10):2062–9.

19. Lesinski M, Prieske O, Granacher U. Effects and dose-response relationships of

resistancetraining on physical performance inyouth athletes: a systematic review

and meta-analysis. Br J Sports Med. 2016;50(13):781–95.

20. Lloyd RS, Cronin JB, Faigenbaum AD, et al. The National Strength and

Conditioning Association position statement on long-term athletic development.

J Strength Cond Res. 2016;30(6):1491–509.

21. Lloyd RS, Faigenbaum AD, Stone MH, et al. Position statement on youth resistance

training: the 2014 International Consensus. Br J Sports Med. 2014;48(7):498–505.

22. Lopes V, Rodriques L, Maia A, Malina R. Motor coordination as a predictor of

physical activity in childhood. Scand J Med Sci Sports. 2011;21(5):663–9.

23. Moliner-Urdiales D, Ruiz JR, Ortega FB, et al; AVENA and HELENA Study Groups.

Secular trends in health-related physical fitness in Spanish adolescents: the

AVENA and HELENA studies. J Sci Med Sport. 2010;13(6):584–8.

24. Myer GD, Faigenbaum AD, Edwards NM, Clark JF, Best TM, Sallis RE. Sixty

minutes of what? A developing brain perspective for activating children with an

integrative approach. Br J Sports Med. 2015;49(23):1510–6.

25. Myer GD, Sugimoto D, Thomas S, Hewett TE. The influence of age on the

effectiveness of neuromuscular training to reduce anterior cruciate ligament injuries

in female athletes: a meta-analysis. Am J Sports Med. 2013;41(1):203–15.

26. Ratamess N. ACSM’s Foundations of Strength Training and Conditioning.

Philadelphia (PA): Lippincott, Williams and Wilkins; 2012. 500 p.

27. Robinson LE, Stodden DF, Barnett LM, et al. Motor competence and its effect on

positive developmental trajectories of health. Sports Med. 2015;45(9):1273–84.

28. Seefeldt V. Developmental motor patterns: implications for elementary school

physical education. In: Nadeau K, Newell K, Roberts G, editors. Psychology of Motor

Behavior and Sport. Champaign (IL): Human Kinetics; 1980. p. 314–23.

29. Smith JJ, Eather N, Morgan PJ, Plotnikoff RC, Faigenbaum AD, Lubans DR. The

health benefits of muscular fitness for children and adolescents: a systematic

review and meta-analysis. Sports Med. 2014;44(9):1209–23.

30. Stodden D, Langendorfer S, Roberton MA. The association between motor skill

competence and physical fitness in young adults. Res Q Exerc Spo rt. 2009;80(2):223–9.

31. Tremblay MS, Gray CE, Akinroye K, et al. Physical activity of children: a global matrix of

grades comparing 15 countries. JPhysActHealth. 2014;11 suppl 1:S113–25.

32. Visek A, Achrati S, Manning H, McDonnell K, Harris B, Dipietro L. The fun

integration theory: toward sustaining children and adolescents sport

participation. J Phys Act Health. 2015;12(3):424–33.

33. World Health Organization. Global Recommendations on Physical Activity for

Health. Geneva: WHO Press; 2010. 58 p.

Recommended Reading:

•Faigenbaum AD,Westcott W.YouthStrengthTraining. Hum an Kinetics: Champ aign

(IL); 2009.

•Lloyd RS, Oliver JL. Strength and Conditioning for Young Athletes: Science and

Application. New York (NY): Routledge; 2014. 232 p.

•Mediate P, Faigenbaum AD. Medicine Ball for All Kids. Monterey (CA): Health

Learning; 2007.

Disclosure: The authors declare no conflict of interest and do not have any

financial disclosures.

Avery D. Faigenbaum, Ed.D., CSCS, FACSM, is a

full professor in the Department of Health and Exer-

cise Science at The College of New Jersey. His re-

search interests focus on pediatric exercise science,

resistance training, and preventive medicine.

James E. McFarland, Ed.M., CSCS, is a health and

physical education teacher at Hillsborough High School

in New Jersey. He is a USA Weightlifting Senior Level

Coach and has presented on youth strength and condition-

ing at national conferences. He also is an adjunct instruc-

tor in the Department of Health and Exercise Science at

The College of New Jersey.

BRIDGING THE GAP

Despite traditional fears and misinformed concerns

associated with youth resistance training, new insights

into the designof youth fitness programs have highlighted

the importance of enhancing muscular fitness during

childhood and continuing participation in strength-building

activities throughout adolescence. Although factors such as

heredity, training experience, and health habits (e.g., nutrition

and sleep) will influence the rate and magnitude of adaptation,

seven principles that determine the effectiveness of youth

resistance training are the principles of (a) Progression,

(b) Regularity, (c) Overload, (d) Creativity, (e) Enjoyment, (f)

Socialization, and (g) Supervision. These basic principles can

be remembered as the PROCESS of youth resistance training.

RESISTANCE TRAINING FOR KIDS

22 ACSM’sHealth & Fitness Journal

September/October 2016

Treinamento pliométrico e melhora da força explosiva: Estudo experimental em crianças e jovens de Maputo, Moçambique

Article

Full-text available

Aug 2023

As principais controvérsias relacionadas à participação de crianças e jovens em programas de treinamento de força estão relacionadas à falta de adaptação desses programas de treinamento, supervisão qualificada e ensino correto das técnicas. Essa lacuna científica refere-se ao uso do modelo pliométrico de iniciação esportiva. Para o contexto de Maputo, Moçambique; e com o objetivo de buscar modelos de intervenção que influenciem o desenvolvimento da força explosiva: analisa-se o efeito do programa de treinamento pliométrico de 8 semanas no desenvolvimento da força explosiva em crianças púberes. O estudo envolveu 60 crianças púberes, divididas em dois grupos com base na faixa etária e sexo. Essas crianças foram submetidas a testes antropométricos. A força explosiva foi avaliada usando baterias de testes de salto horizontal, testes anaeróbicos baseados em corrida e salto vertical; com o método de salto de contramovimento. Os dados foram analisados com o programa estatístico SPSS, 21.0, com nível de significância de 5%. Adicionalmente, testes t de Student inferenciais de medidas pareadas e Análise de Variância foram aplicados para avaliar os resultados das variáveis somáticas e parâmetros de força explosiva, no Pré e Pós-teste. Como resultado, observou-se efeito significativo do programa de treinamento pliométrico, com resultados estatisticamente significativos em todos os parâmetros de avaliação de força no grupo experimental. Ao mesmo tempo, proporcionou uma melhora nas variáveis de aptidão somática, sem expor crianças pequenas a lesões. Palavras-chave: treino pliométrico, força explosiva, Maputo-Moçambique.

Biophysics of ACL injuries

Article

Full-text available

Nov 2024
Mol Cell Biomech

Anterior Cruciate Ligament (ACL) injuries rank among the most prevalent and severe types of injuries, significantly impacting both athletes and non-athletes alike. These injuries not only result in immediate physical impairment, such as intense pain, substantial swelling, and a marked loss of mobility, but also carry long-term health consequences that can alter a person’s quality of life. Chronic pain, persistent instability, and an increased risk of developing osteoarthritis are among the lasting effects that can follow an ACL injury. An in-depth understanding of the biophysics behind ACL injuries is paramount for devising effective prevention and treatment protocols. Biophysics, which combines principles from physics with biological systems, provides crucial insights into the mechanical and structural integrity of the ACL and its susceptibility to injury under various conditions. This systematic review aims to collate and synthesize the current knowledge surrounding the biophysical mechanisms that underlie ACL injuries. The review encompasses a range of factors, including the biomechanical forces that place stress on the ligament, anatomical structures that may predispose individuals to injury, and physiological conditions that affect ligament health and resilience. Each of these factors plays a crucial role in the incidence and severity of ACL injuries. Biomechanical forces, for example, can involve sudden changes in direction or impact during physical activity, leading to excessive stress on the ACL. Anatomical factors might include variations in bone structure or ligament alignment that inherently increase the risk of injury. Additionally, physiological conditions such as muscle strength, flexibility, and overall ligament health can influence the likelihood and extent of an ACL injury. The findings of this review underscore the necessity of adopting integrated approaches in both injury prevention and rehabilitation. Such approaches must consider the multifaceted nature of ACL injuries, involving not only mechanical and anatomical aspects but also physiological and possibly even genetic factors. By emphasizing a multi-faceted understanding, interventions can be more effectively tailored to address the complex interplay of elements that contribute to ACL injuries. This holistic approach can lead to better outcomes for those at risk of or recovering from ACL injuries, enhancing the efficacy of prevention strategies and rehabilitation protocols.

Biophysics of ACL Injuries

Preprint

Full-text available

Oct 2024

Anterior Cruciate Ligament (ACL) injuries rank among the most prevalent and severe types of injuries, significantly impacting both athletes and non-athletes alike. These injuries not only result in immediate physical impairment, such as intense pain, substantial swelling, and a marked loss of mobility, but also carry long-term health consequences that can alter a person's quality of life. Chronic pain, persistent instability, and an increased risk of developing osteoarthritis are among the lasting effects that can follow an ACL injury. An in-depth understanding of the biophysics behind ACL injuries is paramount for devising effective prevention and treatment protocols. Biophysics, which combines principles from physics with biological systems, provides crucial insights into the mechanical and structural integrity of the ACL and its susceptibility to injury under various conditions. This systematic review aims to collate and synthesize the current knowledge surrounding the biophysical mechanisms that underlie ACL injuries. The review encompasses a range of factors, including the biomechanical forces that place stress on the ligament, anatomical structures that may predispose individuals to injury, and physiological conditions that affect ligament health and resilience. Each of these factors plays a crucial role in the incidence and severity of ACL injuries. Biomechanical forces, for example, can involve sudden changes in direction or impact during physical activity, leading to excessive stress on the ACL. Anatomical factors might include variations in bone structure or ligament alignment that inherently increase the risk of injury. Additionally, physiological conditions such as muscle strength, flexibility, and overall ligament health can influence the likelihood and extent of an ACL injury. The findings of this review underscore the necessity of adopting integrated approaches in both injury prevention and rehabilitation. Such approaches must consider the multifaceted nature of ACL injuries, involving not only mechanical and anatomical aspects but also physiological and possibly even genetic factors. By emphasizing a multi-faceted understanding, interventions can be more effectively tailored to address the complex interplay of elements that contribute to ACL injuries. This holistic approach can lead to better outcomes for those at risk of or recovering from ACL injuries, enhancing the efficacy of prevention strategies and rehabilitation protocols.

Prescripción de ejercicios de fuerza para niños y adolescentesPrescription of strength training in children and adolescents

Article

Full-text available

Jan 2022

Juan Francisco Félix Saavedra

En la última década, se ha observado un importante incremento de la implementación de programas de entrenamiento de la fuerza en la práctica deportiva en niños y adolescentes. En esta revisión del entrenamiento de la fuerza, se incluyen los potenciales beneficios en la salud, en el acondicionamiento físico, los riesgos y recomendaciones para la población sana, con sobrepeso, obesidad o sedentaria en niños de 7 a 19 años. Las pautas corrientes envuelven la supervisión, la planificación y el correcto aprendizaje de la técnica. Los resultados revelaron que el niño es, desde el punto de vista metabólico, un organismo no especializado, donde las adaptaciones ocurren sin necesidad de un alto nivel de estimulación. La evidencia científica y la experiencia clínica del entrenamiento de la fuerza en niños y adolescentes, como parte de un programa de entrenamiento, manifiestan que es útil, eficaz y seguro si está prescrito y supervisado adecuadamente, con beneficios potenciales para la salud a nivel físico, psicológico y social. Datos recientes indican que los programas de entrenamiento de fuerza, bien estructurados y adecuadamente supervisados por especialistas capacitados, son seguros para los jóvenes y ofrecen beneficios únicos para niños y adolescentes, como aumento de la fuerza y potencia muscular, disminución del riesgo cardiovascular, ayuda al control de peso, fortalece los huesos, aumenta el bienestar psicosocial, mejora las habilidades de rendimiento motor y reduce el riesgo de lesiones en atletas jóvenes.

Influence of Strength Training Variables on Neuromuscular and Morphological Adaptations in Prepubertal Children: A Systematic Review

Article

Full-text available

Mar 2023
Int J Environ Res Publ Health

Strength training in prepubertal children is one of the topics that has aroused the most interest and controversy among training professionals in recent years. Therefore, the aim of the present study was to analyze the available scientific evidence on the influence of strength training variables on morphological and/or neuromuscular adaptations in healthy prepubertal populations with no previous experience in this type of training according to the descriptive sample characteristics. According to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis, 22 studies were selected after a systematic search and selection process using four electronic databases: Google Scholar, PubMed, Scopus, and SPORT Discus. Furthermore, the internal validity of the studies included was assessed using the modified PEDro scale. The sample consisted of 604 prepubertal children (age, 10.02 ± 0.75 years), of whom 473 were boys and 131 were girls, with 104 strength training programs recorded. Strength training resulted in a significant increase in jumping (n = 29) and sprinting (n = 13) abilities. Moreover, muscle strength was increased in 100% of the cases. Morphologically, strength training resulted in a decrease in body fat percentage (n = 19) and an increase in lean body mass (n = 17). With regard to gender, increases in general sport skills and basic physical abilities were significant in males but not in females. Thus, the results are more heterogeneous in girls due to the small number of studies carried out. Therefore, this research provides practical applications for coaches to design and implement more effective training programs to maximize adaptations, enhance physical performance, and reduce injury risk.

CHRONOLOGICAL AGE EFFECTS ON FUCTIONAL MOVEMENT SCREENTM SCORE IN PREADOLESCENTS: A COHORT STUDY

Article

May 2022

Introduction: There is a high prevalence of "motor illiteracy" among the pediatric population. This situation can exert a negative influence on the amount and quality of physical activity, as well as the development of subsequent physical condition. The quality of movement can be known by applying the Functional Movement Screen (FMSTM). However, there are few studies using FMSTM in preadolescent population. Objective: Therefore, the objective of the present study was to examine the scores obtained with the FMSTM by subgroups in preadolescents. Methods: FMSTM was administered according to standard procedures which consist in seven movements and scores (0-3) of each exercise were recorded in 213 preadolescents (13.47±1.9 years). The sample was divided by quartiles of age for analysis [(Q1 N = 53, from 0 to 11.79 years); (Q2 N = 54, from 11.79 to 13.59 years); (Q3 N = 53, from 13.59 to 14.91 years); (Q4 N = 53 over 14 years old). Results: There are differences in the final score between Q1 vs Q3 and Q1 vs Q4 (p <0.05). In the in line lunge the score differences obtained by Q4 are higher than Q1 (-0.58, p≤ 0.001) and Q2 (-0.65, p≤ 0.001). In trunk stability Q4 gets a score higher than Q1 (-0.88) (p≤ 0.001). In leg raising, Q1 scored lower (p <0.05) than Q4 (-0.45). Conclusions: Chronological age can influence the ability to move and the scores on in line lunge, trunk stability and leg raising tests in preadolescents. In addition, Q4 scores better than Q1 and could be associated with the maturational status.

PE teachers' perceived expertise and professional development requirements in the delivery of muscular fitness activity: PE Teacher EmPOWERment Survey

Article

Full-text available

Nov 2022
Phys Educ Sport Pedagog

Muscular fitness (MF) is an important modifiable factor to improve overall health. Schools offer a unique opportunity to deliver MF activity during physical education (PE) and develop competence to engage in various activities across the life course. However, the implementation of school-based MF activity may be impaired by some teachers reporting a lack of expertise and low confidence in the delivery of MF activity. Understanding teachers' thoughts and perceptions regarding the delivery of MF in schools may help guide future research and policy to support MF delivery in UK schools. Following ethical approval, a survey of secondary school PE teachers across the UK was distributed via Twitter. Survey responses were analysed and reported descriptively and thematically. Completed surveys were returned by 194 teachers (61.9% male) from England, Scotland, Wales, and Northern Ireland. Relative to less experienced teachers, those with at least five years' service were 2.2 times more likely to have completed continued professional development (CPD) in MF activity (OR = 2.16; ß = 0.77; 95% CI: 1.25-3.74; p < 0.01), and 1.8 times more likely to use assessments of MF to inform PE programme decision-making (OR = 1.83; ß = 0.60; 95% CI: 1.18-2.82; p < 0.01). Despite the promising contribution school-based PE may have to developing MF, we report a poor understanding of MF activity amongst UK-based PE teachers. CPD is warranted to deliver successful MF interventions in a school setting.

Provision of online information and resources for resistance training in Australian youth sports: A scoping review

Article

Nov 2024

Objectives This study aimed to identify and synthesize online information/resources related to resistance training provided by governing bodies of the ten most popular youth sports in Australia. Design A scoping review. Methods The top 10 organised out-of-school sports were eligible for the review. A systematic search of national sporting organisation and associated websites was conducted, using key search terms. Data were extracted regarding information and/or resources aligning with current international youth muscle-and-bone strengthening activity guidelines (i.e., 5–17 years, three days per week). Results For all ten sports, information/resources on resistance training were provided for athletes or coaches, however the type of information and level of detail varied. There was lack of consistency between guidelines and information provided by sports. Age of commencement recommendations ranged from four years (athletics) to 14 years (Australian football), whilst others suggested resistance training for all ages (gymnastics) or did not provide an explicit age range (tennis and cricket). Regarding frequency, few sports organisations provided a recommendation for how many days per week resistance training should be performed. Some sports alluded to the need for youth to develop muscular fitness to enhance fitness and performance, whilst others focused primarily on the need for resistance training as an injury prevention tool. Conclusions Our findings highlight the gap that exists in the provision of information in relation to resistance training in Australian sports. It is important that national sporting organisations look to educate athletes and coaches (and parents) from grassroots levels on the need for muscular fitness.

How Can Muscle-Strengthening Activities Be Promoted in School Settings?

Chapter

Aug 2024

Ashley Cox

This chapter examines the decline in muscular fitness among youth, highlighting its importance for physical and mental health. Over the last five decades, developed countries have seen a worrying decrease in children’s muscular fitness levels associated with poor motor skills, functional limitations, and adverse health outcomes. Despite its significance in overall physical activity (PA), muscular fitness, which includes muscle strength, endurance, and power, is often neglected in PA guidelines. We discuss muscular fitness dimensions, assessment methods suitable for schools, and the challenges of integrating muscular fitness activities into educational settings. These challenges stem from unclear terminology and guidelines, complicating teachers’ efforts to implement muscular fitness activities. The synergy between muscular fitness and aerobic activity is crucial for addressing exercise deficit disorders in youth. The chapter stresses the need for specific muscular fitness assessment methods and the role of schools in muscular fitness interventions. It highlights the potential benefits of muscular fitness activities on psychosocial health, motor skills, and lifelong PA habits, advocating for better implementation in school curriculums. Additionally, it outlines the obstacles teachers face, such as a lack of confidence and resources, underscoring the importance of professional development to enhance muscular fitness activity integration into whole school and physical education programs.

Efectos del entrenamiento de fuerza sobre el perfil lipídico en niños y adolescentes con sobrepeso y obesidad. Una revisión sistemática

Article

Full-text available

Jan 2024

El desarrollo de enfermedades cardiovasculares (ECV) ateroscleróticas comienza en edades tempranas y está influenciado por factores genéticos y ambientales. La literatura actual propone el entrenamiento de fuerza (EF) como un medio para reducir el riesgo de ECV y mejorar el perfil lipídico en niños y adolescentes con sobrepeso y obesidad. Con el objetivo de examinar los efectos de un programa de EF en este grupo de población, se realizó una revisión sistemática utilizando el protocolo PRISMA y se buscaron estudios en cinco bases de datos (Pubmed, Scopus, the Cochrane Library, Embase y Web of Science). Un total de 11 estudios cumplieron los criterios finales de inclusión. Los resultados de esta revisión indicaron que las intervenciones de EF supervisadas y realizadas al menos 3 días a la semana con una duración de 8 semanas, mejoraron significativamente los parámetros lipídicos del colesterol (CT) y las lipoproteínas de baja densidad (LDL). Los programas de EF pueden ser considerados como un tratamiento no farmacológico adecuado para mejorar el perfil lipídico y la salud cardiovascular de niños y adolescentes con sobrepeso y obesidad.

Physical Activity of Children: A Global Matrix of Grades Comparing 15 Countries

Article

Full-text available

May 2014

The National Strength And Conditioning Association Position Statement On Long-Term Athletic Development

Article

Full-text available

Feb 2016

There has recently been a growing interest in long-term athletic development for youth. Due to their unique physical, psychological and social differences, children and adolescents should engage in appropriately prescribed exercise programs that promote physical development to prevent injury and enhance fitness behaviours that can be retained later in life. Irrespective of whether a child is involved in organized sport or engages in recreational physical activity, there remains a need to adopt a structured, logical and evidence-based approach to the long-term development of athleticism. This is of particular importance considering the alarmingly high number of youth who fail to meet global physical activity recommendations and consequently present with negative health profiles. However, appropriate exercise prescription is also crucial for those young athletes that are physically underprepared and at risk of overuse injury due to high volumes of competition and an absence of preparatory conditioning. Whether the child accumulates insufficient or excessive amounts of exercise, or falls somewhere between these opposing ends of the spectrum, it is generally accepted that the young bodies of modern day youth are often ill-prepared to tolerate the rigors of sports or physical activity. All youth should engage in regular physical activity and thus should be viewed as 'athletes' and afforded the opportunity to enhance athleticism in an individualized, holistic and child-centred manner. Due to the emerging interest in long-term athletic development, an authorship team was tasked on behalf of the National Strength and Conditioning Association (NSCA) to critically synthesize existing literature and current practices within the field and to compose a relevant position statement. This document was subsequently reviewed and formally ratified by the NSCA Board of Directors. Figure 1 provides a list of the 10 pillars of successful long-term athletic development, which summarize the key recommendations detailed within the consensus statement. With these pillars in place, it is believed that the NSCA can (i) help foster a more unified and holistic approach to youth physical development, (ii) promote the benefits of a lifetime of healthy physical activity, and (iii) prevent and/or minimize injuries from sports participation for all boys and girls. Copyright (C) 2016 by the National Strength & Conditioning Association.

Effects and dose-response relationships of resistance training on physical performance in youth athletes: A systematic review and meta-analysis

Article

Full-text available

Jul 2016

Objectives To quantify age, sex, sport and training type-specific effects of resistance training on physical performance, and to characterise dose–response relationships of resistance training parameters that could maximise gains in physical performance in youth athletes. Design Systematic review and meta-analysis of intervention studies. Data sources Studies were identified by systematic literature search in the databases PubMed and Web of Science (1985–2015). Weighted mean standardised mean differences (SMDwm) were calculated using random-effects models. Eligibility criteria for selecting studies Only studies with an active control group were included if these investigated the effects of resistance training in youth athletes (6–18 years) and tested at least one physical performance measure. Results 43 studies met the inclusion criteria. Our analyses revealed moderate effects of resistance training on muscle strength and vertical jump performance (SMDwm 0.8–1.09), and small effects on linear sprint, agility and sport-specific performance (SMDwm 0.58–0.75). Effects were moderated by sex and resistance training type. Independently computed dose–response relationships for resistance training parameters revealed that a training period of >23 weeks, 5 sets/exercise, 6–8 repetitions/set, a training intensity of 80–89% of 1 repetition maximum (RM), and 3–4 min rest between sets were most effective to improve muscle strength (SMDwm 2.09–3.40). Summary/conclusions Resistance training is an effective method to enhance muscle strength and jump performance in youth athletes, moderated by sex and resistance training type. Dose–response relationships for key training parameters indicate that youth coaches should primarily implement resistance training programmes with fewer repetitions and higher intensities to improve physical performance measures of youth athletes.

Motor Competence and its Effect on Positive Developmental Trajectories of Health

Article

Full-text available

Jul 2015
SPORTS MED

In 2008, Stodden and colleagues took a unique developmental approach toward addressing the potential role of motor competence in promoting positive or negative trajectories of physical activity, health-related fitness, and weight status. The conceptual model proposed synergistic relationships among physical activity, motor competence, perceived motor competence, health-related physical fitness, and obesity with associations hypothesized to strengthen over time. At the time the model was proposed, limited evidence was available to support or refute the model hypotheses. Over the past 6 years, the number of investigations exploring these relationships has increased significantly. Thus, it is an appropriate time to examine published data that directly or indirectly relate to specific pathways noted in the conceptual model. Evidence indicates that motor competence is positively associated with perceived competence and multiple aspects of health (i.e., physical activity, cardiorespiratory fitness, muscular strength, muscular endurance, and a healthy weight status). However, questions related to the increased strength of associations across time and antecedent/consequent mechanisms remain. An individual's physical and psychological development is a complex and multifaceted process that synergistically evolves across time. Understanding the most salient factors that influence health and well-being and how relationships among these factors change across time is a critical need for future research in this area. This knowledge could aid in addressing the declining levels of physical activity and fitness along with the increasing rates of obesity across childhood and adolescence.

Sixty minutes of what? A developing brain perspective for activating children with an integrative exercise approach

Article

Full-text available

Jan 2015

Current recommendations for physical activity in children overlook the critical importance of motor skill acquisition early in life. Instead, they focus on the quantitative aspects of physical activity (eg, accumulate 60 min of daily moderate to vigorous physical activity) and selected health-related components of physical fitness (eg, aerobic fitness, muscular strength, muscular endurance, flexibility and body composition). This focus on exercise quantity in youth may limit considerations of qualitative aspects of programme design which include (1) skill development, (2) socialisation and (3) enjoyment of exercise. The timing of brain development and associated neuroplasticity for motor skill learning makes the preadolescence period a critical time to develop and reinforce fundamental movement skills in boys and girls. Children who do not participate regularly in structured motor skill-enriched activities during physical education classes or diverse youth sports programmes may never reach their genetic potential for motor skill control which underlies sustainable physical fitness later in life. The goals of this review are twofold: (1) challenge current dogma that is currently focused on the quantitative rather than qualitative aspects of physical activity recommendations for youth and (2) synthesise the latest evidence regarding the brain and motor control that will provide the foundation for integrative exercise programming that provide a framework sustainable activity for life. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

ACSM's foundations of strength training and conditioning

Book

Nov 2011

Nicholas Ratamess

Developed by the American College of Sports Medicine, this text offers a comprehensive introduction to the basics of strength training and conditioning based on the latest research findings. ACSM's Foundations of Strength Training and Conditioning is divided into four parts: Foundations, Physiological Responses and Adaptations, Strength Training and Conditioning Program Design, and Assessment. The text focuses on practical applications, enabling students to develop, implement, and assess the results of training programs that are designed to optimize strength, power, and athletic performance. Moreover, the text's clear, straightforward writing style makes it easy to grasp new concepts. © 2012 by American College of Sports Medicine. All rights reserved.

Changes in pediatric waist circumference percentiles despite reported pediatric weight stabilization in the United States: Pediatric waist circumference percentiles in the US

Article

Jun 2016

Background: Obesity is a global health concern but the United States has reported a leveling in obesity rates in the pediatric population. Objective: To provide updated waist circumference (WC) percentile values, identify differences across time and discuss differences within the context of reported weight stabilization in a nationally representative sample of American children. Methods: Percentiles for WC in self-identified African Americans (AA), European Americans (EA) and Mexican Americans (MA) were obtained from 2009-2014 National Health and Nutrition Examination Survey data (NHANES2014). Descriptive trends across time in 10th, 25th, 50th, 75th and 90th percentile WC distributions were identified by comparing NHANES2012 with previously reported NHANESIII (1988-1994). Results: WC increased in a monotonic fashion in AA, EA and MA boys and girls. When compared with NHANESIII data, a clear left shift of percentile categories was observed such that values that used to be in the 90th percentile are now in the 85th percentile. Differences in WC were observed in EA and MA boys during a reported period of weight stabilization. Conclusion and relevance: WC has changed in the US pediatric population across time, even during times of reported weight stabilization, particularly among children of diverse racial/ethnic backgrounds.

Physical Activity, Sedentary Time, and Obesity in an International Sample of Children

Article

Mar 2015

To determine the relationships between moderate-to-vigorous physical activity (MVPA), vigorous physical activity (VPA), sedentary time and obesity in children from 12 countries representing a wide range of human development. The sample included 6,539 children aged 9-11 years. Time in MVPA, VPA and sedentary behaviors were assessed by accelerometry. The body mass index (BMI; kg/m) was used to classify children as obese based on z-scores (>+2 SD) from World Health Organization reference data. The mean (SD) times spent in MVPA, VPA and sedentary behavior were 60 (25) min/day, 18 (11) min/day and 513 (69) min/day, respectively. The overall proportion of the sample that was obese ranged from 5.2% to 24.6% across sites. The odds ratios for obesity were significant for MVPA (0.49; 95% CI: 0.44 - 0.55), VPA (0.41; 0.37 - 0.46) and sedentary time (1.19; 1.08 - 1.30) in the overall sample. The associations of MVPA and VPA with obesity were significant in all 12 sites, whereas the association between sedentary time and obesity was significant in 5 of the 12 sites. There was a significant difference in BMI z-scores across tertiles of MVPA (P<0.001) but not across tertiles of sedentary time in a mutually adjusted model. The results of receiver operating characteristic curve analyses for obesity indicated that the optimal thresholds for MVPA (AUC = 0.64), VPA (AUC = 0.67) and sedentary behavior (AUC = 0.57) were 55 (95% CI: 50-64) min/day, 14 (11-16) min/day and 482 (455-535) min/day, respectively. Greater MVPA and VPA were both associated with lower odds of obesity, independent of sedentary behavior. Sedentary time was positively associated with obesity, but not independent of MVPA. Attaining at least 55 min/day of MVPA is associated with lower obesity in this multi-national sample of children, which supports current guidelines.

Criterion Repetition Maximum Testing

Article

Feb 2014

CRITERION REPETITION MAXIMUM TESTING IS A METHOD OF ASSESSING MUSCULAR STRENGTH THAT FOCUSES ON THE TECHNICAL PERFORMANCE OF A MAXIMAL OR NEAR-MAXIMAL LIFT. ACCEPTED COMMONALITIES OF RESISTANCE EXERCISE PERFORMANCE ARE USED AS PRIMARY CRITERIA FOR SAFELY AND EFFICACIOUSLY EVALUATING MUSCULAR STRENGTH.

The Handbook of Competence and Motivation

Book

Apr 2005

This important handbook provides a comprehensive, authoritative review of achievement motivation and establishes the concept of competence as an organizing framework for the field. The editors synthesize diverse perspectives on why and how individuals are motivated in school, work, sports, and other settings. Written by leading investigators, chapters reexamine central constructs in achievement motivation; explore the impact of developmental, contextual, and sociocultural factors; and analyze the role of self-regulatory processes. Focusing on the ways in which achievement is motivated by the desire to experience competence and avoid experiencing incompetence, the volume integrates disparate theories and findings and sets forth a coherent agenda for future research.