A longitudinal analysis of the U.S. Air Force Reserve Officers’ Training Corps physical fitness assessment

Background:The U.S.Air Force physical fitness assessment(PFA)is used to determine the overall fitness of their personnel.It is currently unknown to what extent the PFA scores of Reserve Officers’Training Corps(ROTC)cadets are affected by mandatory physical training.The purpose of this investigation was to longitudinally examine the PFAs of ROTC cadets over a four-year period,evaluate the results across class ranks,and evaluate the sensitivity of the classification of the tests.Methods:Air Force ROTC cadets performed the PFAs(abdominal circumference,1-min pushups,1-min sit-ups,and a 1.5-mile run)in both the spring(n=26)and fall(n=22)semesters.PFAs were compiled over a four-year period(Spring 2014–Fall 2017)and were performed in accordance with Air Force Instruction 36–2905.A oneway repeated measures ANOVA was performed separately for the fall and spring groups for each dependent variable across the 4 years.Additionally,a one-way between groups ANOVA was performed for each dependent variable during the time point(fall 2015;n=46)with the most recorded cadets for each class rank.Results:Longitudinal assessments revealed a main effect of time(P=0.010)on abdominal circumference;cadets had a smaller abdominal circumference in their freshman year than in their senior year.A main effect of time(P=0.006)was also observed on sit-up quantity;cadets performed more sit-ups in their junior year than in their freshman year.Examining between class ranks during the same year(between-subjects ANOVA)revealed a main effect of class rank on sit-up quantity(P=0.003);the freshmen completed fewer repetitions than the sophomores(P=0.018)and the juniors did(P=0.001).Conclusions:The results indicated that only the sit-up component showed differences between class ranks.These findings suggest that the Air Force PFA may not be sensitive enough to detect changes in physical fitness or distinguish between class ranks regarding physical performance,even after years of training.This limitation may be in part due to the limited duration of training incorporated by the ROTC program(2 h per week),which provided a maintenance effect rather than improvement in physical performance.We recommend that more attention be directed to the efficacy of physical training,the sensitivity of measures included in the PFA,or both.

Analysis and Study on the Effect of PNF Stretching and Resistance Training on the Rehabilitation of Superior Chiasma Syndrome

In this paper,18 subjects with superior chiasma syndrome were analyzed and studied according to the inducement and correction method of superior chiasma syndrome by questionnaire survey,literature review and experimental research.To explore the effect of bad posture on the posture of patients,and to explore the effect of PNF stretching,anti-resistance training and manual loosening on the rehabilitation of patients with superior chiasma.Methods:the subjects were divided into three experimental groups,A,B and C,for 6 weeks,4 times a week for resistance training and PNF stretching training.It has been proved that the population with chest ambushes for a long time will cause the imbalance of muscle strength of shoulder,neck and chest,abnormal physiological curvature of cervical vertebrae and thoracic vertebrae,and induce chronic injury of shoulder and neck muscles and soft tissue,which will lead to symptoms of superior chiasma syndrome.According to the designed rehabilitation training experiment,PNF stretching training and anti-resistance training were carried out for the shoulder and neck muscles which caused superior chiasma syndrome,and the rehabilitation effect was very significant,which was obviously better than that of PNF stretching or resistance training alone.Therefore,PNF stretching and resistance training should be fully combined in rehabilitation training to improve the posture problem in order to achieve twice the result with half the effort.

Manipulative skill competency and health-related physical fitnes in elementary school students

Background：Improving motor skill competency and enhancing health-related physical fitnes are desired learning outcomes for school-aged children.Achieving motor skill competency and a healthy level of physical fitnes lay a foundation for being a physically active person across a lifetime.The purpose of this study was to investigate relationships between levels of manipulative skill competency and physical fitnes for elementary school boys and girls.Methods：In this study,565 fourth-grade students and their 9 physical education teachers were voluntary participants.The students were assessed in 4 basic specialized manipulative skills and 4 fitnes components during regular physical education lessons.Data were analyzed with descriptive statistics,univariate analyses,and multiple R2 liner regression methods.Results：Boys were more proficien at the manipulative skills than girls,while girls had significan higher percentages for meeting the healthy fitnes zone for the fitnes tests than boys.Four manipulative skills significant y predicted progressive aerobic cardiovascular endurance run（PACER）,push-up,and trunk lifts tests at p〈0.05 level,but not curl-up test for both boys and girls.Boys and girls in the skill-competent group significant y outperformed their counterparts in the skill-incompetent group on PACER,push-up,and trunk lifts tests at p〈0.05 level,with an exception of curl-up test.Conclusion：The more competent in manipulative skills,the higher healthy level in cardiovascular endurance,upper-body muscular strength and endurance,and fl xibility the students demonstrated.Demonstrating manipulative skill competence and maintaining a healthy level of physical fitnes are 2 major desired learning outcomes for elementary school students to be able to achieve.

A case study of development and application of a streamlined control and response modeling system for PM_(2.5)attainment assessment in China

This article describes the development and application of a streamlined air control and response modeling system with a novel response surface modeling-linear coupled fitting method and a new module to provide streamlined model data for PM_（2.5） attainment assessment in China.This method is capable of significantly reducing the dimensions required to establish a response surface model,as well as capturing more realistic response of PM_（2.5） to emission changes with a limited number of model simulations.The newly developed module establishes a data link between the system and the Software for Model Attainment Test—Community Edition（SMAT-CE）,and has the ability to rapidly provide model responses to emission control scenarios for SMAT-CE using a simple interface.The performance of this streamlined system is demonstrated through a case study of the Yangtze River Delta（YRD） in China.Our results show that this system is capable of reproducing the Community Multi-Scale Air Quality（CMAQ） model simulation results with maximum mean normalized error 〈 3.5%.It is also demonstrated that primary emissions make a major contribution to ambient levels of PM_（2.5） in January and August（e.g.,more than50%contributed by primary emissions in Shanghai）,and Shanghai needs to have regional emission control both locally and in its neighboring provinces to meet China＇s annual PM_（2.5）National Ambient Air Quality Standard.The streamlined system provides a real-time control/response assessment to identify the contributions of major emission sources to ambient PM_（2.5）（and potentially O_3 as well） and streamline air quality data for SMAT-CE to perform attainment assessments.