Validity of Palpation Recovery Pulse Rate to Estimate Exercise Heart Rate Following Four Intensities of Bench Step Exercise

Abstract

Previous investigations regarding activity during the post-knowledge of results (KR) interval have considered the performance of interference groups over KR-supplied acquisition trials as indicative of effects upon learning. The absence of transfer tests in these studies, however, preclude such an assumption. Indeed, the use of a retention test in the present investigation (no-KR trials following an interpolated phase) provided evidence suggesting that, while activity during the post-KR interval is detrimental to performance, no such assumption can be made regarding this effect upon learning. These findings are discussed relative to recent arguments that some of the commonly accepted “Laws of KR” may be contradictory when applied simultaneously to motor learning and performance.     

Physical activity levels during Dutch primary and secondary school physical education

Abstract

Objective: Physical education (PE) has been attributed an important role in providing young people with physical activity. If sufficiently active, PE lessons could contribute to physical activity levels in youth. Therefore, the purpose of this study was to determine the overall intensity of Dutch primary and secondary school physical education (PE) lessons and the influence of various lesson characteristics on these intensity levels. Methods: Between September 2008 and June 2009 heart rates were measured using the Polar Team System in a nationally distributed sample of 913 students in 40 schools in the Netherlands. Results: Overall percentages lesson time in moderate-to-vigorous physical activity (MVPA) were 46.7% and 40.1% during primary school and secondary school PE respectively. Results indicated a sharp decline in girls’ PE intensity levels at the beginning of secondary school. Furthermore, secondary school boys were more active than girls. The high prevalence of teamgames in the Dutch PE curricula might prevent secondary school girls from attaining similar physical activity levels during PE.     

Effects of official youth taekwondo competitions on jump and strength performance

Abstract

The aim of this study was to investigate differences in athletes’ (7 females, 10 males) motor performances (countermovement jump and handgrip) before and after official youth (13–14 years) taekwondo matches. Exercise load was evaluated by means of the heart rate responses during the match. Independent of round and gender, during the competitions mean heart rate was 187 beats·min^?1 (s=11). During the match, the frequency of heart rate responses above 85% of an individual's maximum heart rate was 77% (s=27). Jump performances showed differences for gender (P=0.044; ES = 0.47) and its interaction with session (P=0.045; ES = 0.49). Female athletes’ post-match countermovement performances were no different from their pre-match performances (pre and post: 22 cm, s=2), whereas male athletes post-match performances (28 cm, s=6) were better than their pre-match performances (25 cm, s=6). Handgrip performances related to the body mass of the athletes showed main effects for session (P=0.017; ES = 0.20) and for gender (P=0.026; ES = 0.47), with no significant interaction. Male athletes showed higher handgrip values (5.8 N·kg^?1, s=0.6) than their female counterparts (5.1 N·kg^?1, s=0.7). For absolute grip strength performances, values were higher pre-match (290.3 N, s=61.4) than post-match (272.4 N, s = 58.3). The heart rate responses indicate that official youth taekwondo competition imposes a high load on athletes. In particular, post-match decreases in isometric grip strength suggest that coaches should better prepare their very young athletes to prevent reductions in muscle force during fighting. Considering that lower limb power remained unaffected or increased depending on gender, further research in this area is strongly recommended.     

No effect of upper body compression garments in elite flat-water kayakers

Abstract

While the effect of lower body compression garments on performance and physiological responses are well documented, no studies have examined the effect of upper body compression garments (UBCG) on upper-body dominant exercise. This study examined the effects of wearing UBCG on performance and physiological responses during simulated flat-water kayaking. Five male (mean values±s: 21.8±2.8 years; 83.5±9.2 kg; 63.0±5.5 ml·kg^?1·min^?1) and two female (mean values±s: 25.0±4.2 years; 71.4±2.7 kg; 51.0±4.8 ml·kg^-1·min^-1) elite flat-water kayakers completed a six-step incremental test followed by a four-minute maximal performance test (4minPT) in both UBCG and control (no shirt or sports training bra) conditions in a randomized counter-balanced order. Heart rate and oxygen consumption (O₂) as well as performance measures (power, distance covered, stroke rate) were recorded during the tests, and blood lactate was measured immediately after each incremental step and three minutes following the 4minPT. Near-infrared spectroscopy-derived measures of blood flow and oxygenation of the flexor carpi radialis were monitored continuously for all tests. No significant differences between the UBCG and control conditions were evident for any performance, cardiorespiratory or oxygenation measure across the incremental step test and 4minPT. It was concluded that wearing UBCG did not provide any significant physiological or performance benefits during simulated flat-water kayaking.     

2000-2010年黑龙江省中小学贫血检出率动态变化趋势

运用专家访谈、数理统计等研究方法,以黑龙江省2000年、2005年、2010年城乡中小学生为调研对象,分析中小学生贫血检出率动态变化趋势,讨论缺铁性贫血对中小学生的危害,并对存在的问题提出建议,为改善中小学生缺铁性贫血问题提供有效数据,同时也为中国学生体质与健康研究组提供可靠数据。     

对参加“全国物理知识竞赛”山东代表队员大脑机能的测试与分析

应用“8 0 .8神经类型量表”和“DJ—A型大脑机能测试仪”对我省参加“全国物理知识竞赛”的山东代表队队员进行测试。结果表明 :我省队员的神经类型分布 ,大多数集中在2— 3型、6— 7型、9— 1 0型 ,大脑机能能力较好 ,并分析了与超常重点班学生、山东某重点中学学生在大脑机能、错漏率等方面的差异 ;参赛队员中的城市队员与农村队员的神经类型比较 ,城市队员神经过程的强度、兴奋和抑制过程稳定性强 ,灵活性好。     

高原地区中长跑运动员心率变异性特征

目的:了解高原地区中长跑运动员心率变异性特征。方法:云南师范大学男子中长跑运动员12名,设为实验组,普通大学生12名,设为对照组。对两组安静状态下10 min短时心率变异性进行时域、频域及非线性分析。结果:实验组时域各项指标平均RR、RMSSD、pNN50、SDNN/HR均显著高于对照组(P0.05,P0.01)。频域各指标中HFn.u.显著高于对照组(P0.05),而LFn.u.显著低于对照组(P0.05),最终LF/HF比值极显著低于对照组(P0.01)。结论:和高原地区普通大学生相比,中长跑运动员具有较高的心率变异性和较大的自主神经调节能力,且与平原地区相应人群无明显差异。     

远距离单手肩上投篮训练方法探讨

讨论影响投篮命中率有7个因素:手法、瞄准的方向、球的旋转、抛物线、协调性、判断反应和心理因素,并提出提高远距离投篮命中率的训练方法.     

调整体育彩票收入分配的可行性研究

近期我国体育彩票销售量经过一段时间的快速增长后,开始进入到一个相对平稳的“停滞期”。究其原因,单一的玩法、较低的返奖率,是销量上不去的主要原因,为使其进一步扩大销量,必须开拓思路、积极创新,给体育彩票注入新的活力和内容。对体育彩票收入分配比例进行重新调整,提高返奖率有利于体育彩票业的发展。     

对我国雅典奥运会电视节目收视状况的分析与思考

运用文献资料法、逻辑分析法等方法,对我国雅典奥运会电视节目收视状况进行了研究。结果表明:奥运会期间体育节目收视率大幅上扬,妇女、儿童等非传统观众群体踊跃参与观赏活动,奥运赛事观赏呈现"全民性"特征;我国选手的表现、观众对项目的兴趣、体育明星的号召力以及节目播出时间是影响奥运赛事收视率的主要因素。在对奥运赛事收视状况进行分析的基础上,提出了若干开发我国奥运会赛事收视市场的合理化建议,为北京奥运会市场开发工作提供了一定的参考和借鉴。