Faigenbaum, AD, Kraemer, WJ, Blimkie, CJR, Jeffreys, I, Micheli, LJ, Nitka, M, and Rowland, TW. Youth resistance training: Updated position statement paper from the National Strength and Conditioning Association. J Strength Cond Res 23(5): S60-S79, 2009-Current recommendations suggest that school-aged youth should participate daily in 60 minutes or more of moderate to vigorous physical activity that is developmentally appropriate and enjoyable and involves a variety of activities (). Not only is regular physical activity essential for normal growth and development, but also a physically active lifestyle during the pediatric years may help to reduce the risk of developing some chronic diseases later in life (). In addition to aerobic activities such as swimming and bicycling, research increasingly indicates that resistance training can offer unique benefits for children and adolescents when appropriately prescribed and supervised (). The qualified acceptance of youth resistance training by medical, fitness, and sport organizations is becoming universal ().Nowadays, comprehensive school-based programs are specifically designed to enhance health-related components of physical fitness, which include muscular strength (). In addition, the health club and sport conditioning industry is getting more involved in the youth fitness market. In the U.S.A., the number of health club members between the ages of 6 and 17 years continues to increase () and a growing number of private sport conditioning centers now cater to young athletes. Thus, as more children and adolescents resistance train in schools, health clubs, and sport training centers, it is imperative to determine safe, effective, and enjoyable practices by which resistance training can improve the health, fitness, and sports performance of younger populations.The National Strength and Conditioning Association (NSCA) recognizes and supports the premise that many of the benefits associated with adult resistance training programs are attainable by children and adolescents who follow age-specific resistance training guidelines. The NSCA published the first position statement paper on youth resistance training in 1985 () and revised this statement in 1996 (). The purpose of the present report is to update and clarify the 1996 recommendations on 4 major areas of importance. These topics include (a) the potential risks and concerns associated with youth resistance training, (b) the potential health and fitness benefits of youth resistance training, (c) the types and amount of resistance training needed by healthy children and adolescents, and (d) program design considerations for optimizing long-term training adaptations. The NSCA based this position statement paper on a comprehensive analysis of the pertinent scientific evidence regarding the anatomical, physiological, and psychosocial effects of youth resistance training. An expert panel of exercise scientists, physicians, and health/physical education teachers with clinical, practical, and research expertise regarding issues related to pediatric exercise science, sports medicine, and resistance training contributed to this statement. The NSCA Research Committee reviewed this report before the formal endorsement by the NSCA.For the purpose of this article, the term children refers to boys and girls who have not yet developed secondary sex characteristics (approximately up to the age of 11 years in girls and 13 years in boys; Tanner stages 1 and 2 of sexual maturation). This period of development is referred to as preadolescence. The term adolescence refers to a period between childhood and adulthood and includes girls aged 12-18 years and boys aged 14-18 years (Tanner stages 3 and 4 of sexual maturation). The terms youth and young athletes are broadly defined in this report to include both children and adolescents.By definition, the term resistance training refers to a specialized method of conditioning, which involves the progressive use of a wide range of resistive loads and a variety of training modalities designed to enhance health, fitness, and sports performance. Although the term resistance training, strength training, and weight training are sometimes used synonymously, the term resistance training encompasses a broader range of training modalities and a wider variety of training goals. The term weightlifting refers to a competitive sport that involves the performance of the snatch and clean and jerk lifts.This article builds on previous recommendations from the NSCA and should serve as the prevailing statement regarding youth resistance training. It is the current position of the NSCA that:

Youth resistance training: updated position statement paper from the national strength and conditioning association.

https://www.archives-pmr.org/article/S0003-9993(03)00030-3/pdf

Analysis of impairments influencing gait velocity and asymmetry of hemiplegic patients after mild to moderate stroke

The current manuscript has been adapted from the official position statement of the UK Strength and Conditioning Association on youth resistance training. It has subsequently been reviewed and endorsed by leading professional organisations within the fields of sports medicine, exercise science and paediatrics. The authorship team for this article was selected from the fields of paediatric exercise science, paediatric medicine, physical education, strength and conditioning and sports medicine.

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Position statement on youth resistance training: the 2014 International Consensus

Within the UK, the “Long Term Athlete Development” (LTAD) model has been proposed by a variety of national governing bodies to offer a first step to considering the approach to talent development. ...

https://www.tandfonline.com/doi/pdf/10.1080/02640414.2010.536849

The Long-Term Athlete Development model: Physiological evidence and application

Many position stands and review papers have refuted the myths associated with resistance training (RT) in chil- dren and adolescents. With proper training methods, RT for children and adolescents can be relatively safe and improve overall health. The objective of this position paper and review is to highlight research and provide recommendations in as- pects of RT that have not been extensively reported in the pediatric literature. In addition to the well-documented increases in muscular strength and endurance, RT has been used to improve function in pediatric patients with cystic fibrosis and cerebral palsy, as well as pediatric burn victims. Increases in children's muscular strength have been attributed primarily to neurological adaptations due to the disproportionately higher increase in muscle strength than in muscle size. Although most studies using anthropometric measures have not shown significant muscle hypertrophy in children, more sensitive measures such as magnetic resonance imaging and ultrasound have suggested hypertrophy may occur. There is no mini- mum age for RT for children. However, the training and instruction must be appropriate for children and adolescents, in- volving a proper warm-up, cool-down, and appropriate choice of exercises. It is recommended that low- to moderate- intensity resistance exercise should be done 2-3 times/week on non-consecutive days, with 1-2 sets initially, progressing to 4 sets of 8-15 repetitions for 8-12 exercises. These exercises can include more advanced movements such as Olympic- style lifting, plyometrics, and balance training, which can enhance strength, power, co-ordination, and balance. However, specific guidelines for these more advanced techniques need to be established for youth. In conclusion, an RT program that is within a child's or adolescent's capacity and involves gradual progression under qualified instruction and supervi- sion with appropriately sized equipment can involve more advanced or intense RT exercises, which can lead to functional (i.e., muscular strength, endurance, power, balance, and co-ordination) and health benefits.

/pdf/canadian-society-for-exercise-physiology-position-paper-4ionq4vbl9.pdf

Canadian Society for Exercise Physiology position paper: resistance training in children and adolescents

Background and Purpose. Computerized 3-dimensional (3-D) motion measurement systems are used by those interested in human motion. The purposes of this study were (1) to determine the limits of accuracy in determining intersegmental angles during pendular motion at varying speeds and (2) to determine changes in accuracy introduced by autodigitization and digitization by experienced manual raters. Methods. Angular speed of a T-shaped pendulum was systematically increased by releasing the pendulum from 4 angles (0° [no movement], 45°, 90°, and 120°). Twelve reference angles calculated from markers placed on the pendulum were estimated over 20 frames for 10 trials at each release position. Results. Mean errors across trials and frames for intersegmental angles reconstructed by a 3-D motion measurement system were within ±1 degree across all release positions. An analysis of variance and a post hoc Tukey test revealed that the mean error for the autodigitized trials was larger than that for the manually digitized trials. For the autodigitized trials, the static trials (release position=0°) produced less mean error than the trials with movement produced. The ICCs showed a high degree of consistency among all raters, ranging from .707 to .999. Conclusion and Discussion. Our findings support the conclusion that under carefully controlled conditions, a 3-D motion measurement system can produce clinically acceptable measurements of accuracy across a range of angular speeds. Furthermore, acceptable accuracy is possible regardless of the digitization method.

/pdf/accuracy-of-digitization-using-automated-and-manual-methods-e3o96tcxlv.pdf

Accuracy of digitization using automated and manual methods

OBJECTIVE To determine the effect of local anesthesia of the palmar digital nerves on forelimb kinematics in Quarter Horses with and without navicular disease. ANIMALS 12 adult Quarter Horses; 5 clinically normal (sound) and 7 with navicular disease. PROCEDURE Kinematic measurements were made on adult horses trotting on a treadmill, before and after palmar digital nerve block (PDNB). Twenty-three displacement, joint angle, and temporal gait measurements of the right forelimb and head were made for 5 strides in each horse. Initial (before local anesthesia) right forelimb measurements were obtained after a left forelimb PDNB. Kinematic measurements were compared before and after PDNB of the right forelimb by multiple ANOVA with an alpha = 0.05, adjusted for posthoc comparisons by Bonferroni correction. RESULTS In sound horses, the only significant change in kinematic measurements after PDNB nerve block was in the maximum extension of the metacarpophalangeal joint at mid-stance, which was decreased by an angle of 2 degrees. In horses with navicular disease, mean maximum extension of the metacarpophalangeal joint during stance phase and maximum flexion of the carpal joint during swing phase were significantly increased after PDNB. Also, total stance phase, cranial stance phase, and break-over durations were significantly shorter. In horses with navicular disease, differences between minimum head heights during stance phase of each forelimb and total vertical head excursion during a complete stride were significantly smaller after PDNB. CONCLUSION Several kinematic measurements of gait can be used to determine improvement of lameness in horses with navicular disease after PDNB block while trotting on a treadmill.

Effects of anesthesia of the palmar digital nerves on kinematic gait analysis in horses with and without navicular disease.

Background and Purpose. Three-dimensional computerized gait analysis continues to grow in use among physical therapists and other clinical specialists interested in quantitative data regarding human ambulation. This study documented the accuracy of reconstructed angular estimates under static and dynamic conditions using the Ariel Performance Analysis System™. Methods. Angular velocity was systematically increased by raising the release position of a T-shaped pendulum. Angular velocities were examined by releasing the pendulum from four angles (0°-static, 45°, 90°, and 120°). Twelve reference angles were estimated over 20 autodigitized frames for 10 trials at each release position. Intraclass correlation coefficients (ICCs) and analysis-of-variance (ANOVA) procedures were used to test the hypothesis that the error of angular estimates grows with increasing angular velocity. Results. Mean errors of the reconstructed angles were consistently within ±1.0 degree, regardless of angular velocity. An ANOVA revealed a statistically significant angular velocity effect, characterized by release position. The 90-degree release position produced the greatest error, followed by the 120-, 45-, and 0-degree release positions. The error was not significantly different between the 120- and 45-degree release positions. Intraclass correlation coefficients greater than .90 were found for all frame-to-frame angular velocities, except for the 90-degree release position. The angle estimates consistently underestimated the reference angles, regardless of release position. Conclusion and Discussion. The results suggest that clinically accurate angular estimates can be obtained across the range of angular velocities used in this study.

/pdf/accuracy-of-reconstructed-angular-estimates-obtained-with-42qo5xl1tf.pdf

Accuracy of Reconstructed Angular Estimates Obtained With the Ariel Performance Analysis System

Purpose: To review literature regarding clinical response to injections of botulinum toxin type A for a variety of painful disorders of involuntary muscular contraction Methods: A MEDLINE search for the headings 'botulinum toxin', 'myofascial pain' and 'pain' was performed for the period 1966 to September 1997 Results: Eighteen references including 463 subjects were generated Seven studies included 'pain' or 'myofascial pain' within the article title, while the remaining references reported pain response within the context of treatment for underlying spasticity, cervical dystonia, fibromyaJgia, focal dystonia, hemifacial spasm, painful dystonia of Parkinson's disease, pain of chronic pancreatitis, writer's cramp and masseteric hypertrophy Results of pain response in the cited studies were favorable in all except in fibromyalgia and chronic pancreatitis The authors discuss instruments to measure pain intensity and physical functioning for future research and introduce a new instrument that includes self-reported pain assessment linked to joint position Conclusion: Evidence suggests that BTX-A effectively reduces painful muscular contractions associated with a variety of neurologic conditions Further research is needed to define conditions in which injections will be most effective © 1998 Elsevier Science Ireland Ltd

Treatment of painful muscle syndromes with botulinum toxin: A review

The objectives of this study were to: (1) demonstrate the use of computerized, three-dimensional gait analysis as a functional assessment instrument following clinical intervention; and (2) objectively quantify the effects of focal muscle denervation via botulinum toxin type A (BTXA) injection in a hemiparetic patient with lower extremity spasticity following traumatic brain injury (TBI). A desired outcome of this intervention was to realize kinematics more closely resembling those reported for normal patients. The design was a single-subject case study. Ten trials of walking gait were analysed pre-injection (PI), 1 week post-injection (1PO) and 4 weeks post-injection (4PO). The PI and 1PO sessions were found to be appreciably different from the 4PO on the joint angles of the ankle and knee at each phase of the gait cycle. These differences resulted in a reduced asymmetry of ambulation. Stride time, stance time, percentage stance time, percentage swing time and walking speed improved, showing progress towards a more efficient gait pattern. Decreased stride time and increased walking speed supported improved functional ability. The inter-trial variability of the gait parameters showed the analysis to be a consistently reproducible protocol. Conclusions based on the results included encouraging findings for the efficacy of botulinum toxin A as a therapy for the reduction of spasticity.

Daniel J. Wilson

Papers

Accuracy of digitization using automated and manual methods

Effects of anesthesia of the palmar digital nerves on kinematic gait analysis in horses with and without navicular disease.

Accuracy of Reconstructed Angular Estimates Obtained With the Ariel Performance Analysis System

Treatment of painful muscle syndromes with botulinum toxin: A review

Kinematic changes following botulinum toxin injection after traumatic brain injury