Effect of nutrition supplement education on nutrition supplement knowledge among high school students from a low-income community

Research has shown that adolescents from low-income communities receive less educational resources and support and may possess insufficient knowledge of nutrition and sport supplements to make health conscious decisions. The purpose of this investigation was to determine the effectiveness of a nutrition supplement educational intervention in improving the nutrition supplement knowledge of adolescents from a low-income community. Thirty-nine high school students from a low-income community were separated into experimental (E) (n = 22) and control (C) (n = 17) groups. E received 5 nutrition lessons on various nutrition and sport supplement topics. C did not receive any nutrition education. E consisted of 5 freshmen, 5 sophomores, 6 juniors, and 6 seniors. The ethnic backgrounds of E were: 15 African-Americans, 3 Hispanic-Americans, and 4 others. There were 14 females and 8 males in E. C consisted of 9 freshmen, 1 sophomore, 4 juniors, and 3 seniors. The ethnic backgrounds of C were: 14 African-Americans, 1 Hispanic-American, and 2 others. There were 10 females and 7 males in C. Both groups were administered a validated nutrition and sport supplement questionnaire at baseline and post-intervention that consisted of 28 questions. Mean baseline knowledge scores for E and C were 5.73 ± 3.34 and 8.18 ± 3.82, respectively (p = 0.040). Post-intervention scores were: 14.45 ± 4.81 and 7.82 ± 4.79 for E and C, respectively (p = 0.0001). These results indicate that a short-term nutrition education program can significantly improve nutrition and sport supplement knowledge in high school students of low socioeconomic status.     

针刺穴位对短跑运动能力实践无累积效应原因分析

笔者将运动成绩相对集中的21名体育教育专业大学一年级学生随机分为三组进行实验研究,得出的 结论是:针刺穴位对短跑运动能力即时效应明显,而累积效应不明显。本文通过对实验过程、实验施加因素 的分析,探讨了针刺穴位对短跑运动能力提高累积效应不明显的原因,为今后研究针灸对运动能力的影响提 供参考。     

浅析运动疲劳血中SOD与LPO等指标变化的关系

在剧烈运动时,由于大量的代谢产物堆积,使机体的内环境稳定性趋于失调,脂质过氧化过程加强,酸碱平衡紊乱,细胞的正常代谢和功能受到干扰,因而使机体的工作能力下降,产生疲劳。本文将着重对家兔运动时血液中超氧化物岐化酶(SOD)、过氧化脂质(LPO)、乳酸脱氢酶(LDH)和乳酸(LA)浓度的变化与运动性疲劳的关系作一初步探讨。     

Muscular and cardiorespiratory effects of pseudoephedrine in human athletes

AIMS: Pseudoephedrine (PSE) is a readily available over-the-counter nasal decongestant which is structurally similar to amphetamine and is included on the International Olympic Committee's list of banned substances. However to date, little research has supported its putative ergogenic effect. This study investigated whether a 180 mg dose of PSE ingested 45 min prior to exercise enhanced short-term maximal exercise performance and/or altered related physiological variables. METHODS: A randomised, double-blind, crossover study in 22 healthy male athletes. RESULTS: Maximum torque (mean +/- s.d., n = 22) produced in an isometric knee extension exercise was 321.1+/-62.0 Nm (PSE) and 295.7+/-72.4 Nm (placebo), and peak power obtained on the 'all-out' 30 s cycle test was 1262.5+/-48.5 W (PSE) and 1228.4+/-47.1 W (placebo) (P<0.01, P<0.03, respectively). Subjects were estimated to be producing 96.9+/-2.4% of their maximal possible isometric leg extension force after PSE ingestion, but only 95.3+/-2.4% when PSE was not ingested. Bench press tasks and total work during the cycle test were not affected by the ingestion of PSE. Lung function was altered following ingestion of PSE (P<0.05) with FEV1 and FVC significantly increased (P<0.02, P<0.01, respectively) although the FEV1/FVC ratio was not altered. Heart rate was significantly elevated by the ingestion of PSE immediately following the 30 s cycle sprint (P<0.01) however, lactate concentration was not altered by the ingestion of PSE. CONCLUSIONS: The administration of a 180 mg dose of PSE increased maximum torque, produced in an isometric knee extension and produced an improvement in peak power during maximal cycle performance, as well as improving lung function.     

Mental Practice in Sport Psychology: Where Have We Been,Where Do We Go?

Research on mental practice for sport performance enhancement is reviewed in this article, which discusses current trends in the use of mental practice by elite athletes and coaches, research findings that appear conclusive, trends supported by research results, and theories to explain mental practice. Recommendations for research designs include operationally defining "mental practice," organizing classifications of tasks studied, describing mental practice content, assuring equal trials, matching participants, using placebo controls and collecting follow-up data, and considering more complex research designs. Recommendations for practice Include (a) teaching imagery skills, (b) Including relaxation, (c) increasing repetitions of trials, (d) defining the content precisely, (e) using stimulus and response propositions, and (f) alternating physical and mental practice.     

Effect of total knee arthroplasty on recreational and sporting activity

BACKGROUND: Common concerns of patients undergoing total knee arthroplasty (TKA) are whether they can continue with certain recreational and sporting activities or even commence new ones after the procedure. The present study was designed to determine preoperative and postoperative activities, the numbers participating and the time to resume these activities. METHODS: Between 1 and 2 years after TKA, patients who had undergone 144 arthroplasties, were surveyed by postal questionnaire to ascertain how the arthroplasty had affected their recreational and sporting ability. Their preoperative and postoperative activity along with the time to resume was recorded. The Oxford knee score and estimate of physical activity was also collected. RESULTS: Out of the 144 TKA performed, 122 participated in sport and recreational activity preoperatively and 108 participated postoperatively. Patients stated that the surgery had a beneficial effect on their performance of sporting and recreational activities although the number of sporting events decreased. By multiplying individuals by the number of activities they participated in, there were 254 occurrences of sport and recreational activities preoperatively giving a mean for the group of 1.76 sports/patient. Postoperatively this had reduced to 204, giving a mean of 1.41. Three activities showed a significant change for individual patients from pre- to postoperation. Those which showed an increase were exercise walking, where 19 patients (13.2%) who did not walk before surgery took up walking afterwards (P < 0.006) and aqua aerobics, where five took up aqua aerobics postoperatively for the first time (P < 0.025). Golf was the only sport which had a significant fall in participation from pre- to postoperation, with 10 out of 19 golfers giving up (P < 0.025). CONCLUSION: The present study has shown that patients are adopting lower impact activities to participate in after TKA. The total number of patients performing a sport decreases postoperatively and the total amount of sport played decreases. These data will help to counsel patients.     

The effect of dance training on joint mobility,muscle flexibility,speed and agility in young cross-country skiers--a prospective controlled intervention study

We evaluated a short-term (3 months) and a long-term (8 months) effect of dance training on joint mobility and muscle flexibility of the spine, hip and ankle and on speed and agility in young cross-country skiers. Twenty elite cross-country skiers - aged 12-15 years - participated in the study. Five males and five females received dance training (intervention group) and five males and five females did not dance (reference group). Joint mobility and muscle flexibility of the spine, hip and ankle joints were measured using a goniometer, a kyphometer, a measuring tape and a ruler. Two sports-related functional tests - the slalom-test and the hurdle-test - were also performed. These measurements/tests were performed before the start of the dancing period and after 3 and 8 months. The subjects from the intervention group increased their speed with 0.3 s after 3 (P = 0.05) and 8 months (P = 0.02), respectively, when measured with the slalom-test. They also improved their speed and agility according to the hurdle-test after 3 months with 0.8 s (P = 0.000) and 8 months with 0.6 s (P = 0.01). Furthermore, they increased flexion-extension of the thoracic spine with 7.5 degrees after 3 months (P = 0.05) and with 9 degrees degrees after 8 months (P = 0.03) and lateral flexion of the spine with 0.04 m (P = 0.005) and 0.03 m (P = 0.02) after 3 and 8 months, respectively. The reference group was impaired or unchanged in the studied parameters after both 3 and 8 months. We conclude that dance training has a positive effect on speed and agility and on joint mobility and muscle flexibility in flexion-extension and lateral flexion of the spine in young cross-country skiers.     

The physiology of world‐class sprint skiers

The present study investigated the physiological characteristics of eight world‐class (WC) and eight national‐class (NC) Norwegian sprint cross country skiers. To measure the physiological response and treadmill performance, the skiers performed a submaximal test, a peak aerobic capacity (VO_2peak) test, and a peak treadmill speed (V_peak) test in the skating G3 technique. Moreover, the skiers were tested for G3 acceleration outdoors on asphalt and maximal strength in the lab. The standard of sprint skating performance level on snow was determined by International Ski Federation points, and the training distribution was quantified. WC skiers showed 8% higher VO_2peak and twice as long a VO₂ plateau time at the VO_2peak test, and a higher gross efficiency at the submaximal test (all P<0.05). Furthermore, WC skiers showed 8% higher V_peak (P<0.05), but did not differ from NC skiers in acceleration and maximal strength. WC skiers performed more low‐ and moderate‐intensity endurance training and speed training (both P<0.05). The current results show that aerobic capacity, efficiency, and high speed capacity differentiate WC and NC sprint skiers and it is suggested that these variables determine sprint skiing performance.     

Physical activity levels of overweight and nonoverweight high school students during physical education classes

Background:  This study examined physical activity (PA) levels of overweight and nonoverweight African American and Caucasian students (n = 198) during game play in physical education classes.
Methods:  Body fat percentages (%BFs) were determined using the skinfold technique and Slaughter et al prediction equations. Girls were classified as overweight if their %BF was ≥32; boys were classified as overweight if their %BF was ≥25. PA was monitored using pedometers during flag football, ultimate Frisbee, and soccer game play. Three 2 (weight classification) × 2 (gender) × 2 (race) factorial analyses of variance were conducted.
Results:  Results indicated no significant difference in steps per minute between overweight and nonoverweight students regardless of game. Males were more active than females, and Caucasians were more active than African Americans.
Conclusions:  The most important implication of the current study is that the overweight and nonoverweight students accumulated similar amounts of PA during physical education. This emphasizes the importance physical education plays in providing both overweight and nonoverweight students with opportunities for PA. For many students, it may be their only source of regular PA.