The effect of acute caffeine ingestion on upper body anaerobic exercise and cognitive performance

Abstract

The current study examined the effect of acute caffeine ingestion on mean and peak power production during upper body Wingate test (WANT) performance, rating of perceived exertion, readiness to invest effort and cognitive performance. Using a double-blind design, 12 males undertook upper body WANTs, following ingestion of caffeine (5?mg*kg^?1) or placebo. Pre-substance ingestion, 60?mins post substance ingestion and post exercise participants completed measures of readiness to invest physical and mental effort and cognitive performance. Peak power was significantly higher (P?=?.026), fatigue index greater (P?=?.02) and rating of perceived exertion lower (P?=?.025) in the presence of caffeine. Readiness to invest physical effort was also higher (P?=?.016) in the caffeine condition irrespective of time point (pre, 60?mins post ingestion and post exercise). Response accuracy for incongruent trials on the Flanker task was superior in the presence of caffeine (P?=?.006). There was a significant substance?×?time interaction for response speed in both congruent and incongruent conditions (both P?=?.001) whereby response speeds were faster at 60?mins post ingestion and post exercise in the caffeine condition, compared to placebo. This is the first study to examine the effects of caffeine ingestion on this modality of exercise and suggests that caffeine ingestion significantly enhances peak power, readiness to invest physical effort, and cognitive performance during WANT performance.     

Response of brain-derived neurotrophic factor to combining cognitive and physical exercise

Purpose: Brain-derived neurotrophic factor (BDNF) is well known for its potential to promote brain plasticity. It has been proposed that combining cognitive and physical exercise (CCPE) may have the potential to generate more synergistic benefits in cognitive function than either cognitive exercise (CE) or physical exercise (PE) alone. The purpose of this study was to examine acute responses of peripheral BDNF levels and cognitive performance to CE, PE, and CCPE.

Methods: Thirteen healthy adult men participated in four experimental sessions; a 30-min CE, a 30-min cycling PE at an intensity of 60% peak oxygen uptake, a 30-min CCPE at the same intensity as PE, and a 30-min session of complete rest. Plasma BDNF levels and cognitive performance were measured before and after each session.

Results: Both PE and CCPE significantly increased plasma BDNF levels (p?p?≥?.05), and there was no significant difference in peripheral BDNF levels between PE and CCPE (p?≥?.05). No session induced a significant change in cognitive performance (p?≥?.05).

Conclusions: Our study suggests that CE and PE have different responses of peripheral BDNF levels and that CCPE had no additional or synergistic effect on peripheral BDNF levels compared with PE alone. This study offers further insights into the potential mechanisms underlying the respective roles of CE, PE, and CCPE for peripheral BDNF levels and cognitive performance.     

运动认知、情绪与竞技水平的关系性研究

为了明确运动认知、情绪及竞技水平的关系,通过问卷调查、文献资料和数理统计等方法,对79名国家现役优秀跆拳道运动员进行了调查研究。结果表明:运动认知和情绪对运动员的竞技水平存在显著的直接效应,且具有典型的预测效应,其中,运动认知对竞技水平还存在显著的间接性影响(0.241),情绪成为一个重要的调节变量。同时,在对运动认知和情绪对竞技水平的各路径分析中,仅社会期待焦虑未呈现显著性,其他各维度均表现出显著性的作用。为此,建议重视竞技运动中运动认知和情绪的作用及其两者之间的关系,将认知和情绪作为运动员竞技水平的重要预测和控制变量。     

The effect of acute caffeine ingestion on upper and lower body anaerobic exercise performance

Abstract

The current study examined the effect of acute caffeine ingestion on mean and peak power production, fatigue index and rating of perceived exertion (RPE) during upper body and lower body Wingate anaerobic test (WANT) performance. Using a double-blind design, 22 males undertook one upper body and one lower body WANT, 60?min following ingestion of caffeine (5?mg*kg^?1) and one upper body and one lower body WANT following ingestion of placebo (5?mg*kg^?1 Dextrose). Peak power was significantly higher (P?=?.001) following caffeine ingestion in both upper and lower body WANT. Peak power and mean power was also significantly higher during lower body, compared to upper body WANTs irrespective of substance ingested. However, caffeine ingestion did not enhance mean power neither in upper nor lower-body WANT. There were no significant differences in mean fatigue index as a consequence of substance ingested or mode of exercise (all P?>?0.05). For RPE there was also a significant substance ingested X mode interaction (P?=?.001) where there were no differences in RPE between caffeine and placebo conditions in lower body WANTs but significantly lower RPE during upper body WANT in the presence of caffeine compared to placebo (P?=?.014). This is the first study to compare the effects of caffeine ingestion on upper and lower body 30-second WANT performance and suggests that caffeine ingestion in the dose of 5?mg*kg^?1 ingested 60?min prior to exercise significantly enhances peak power when data from upper and lower body WANTs are combined.     

Confounding compression: the effects of posture,sizing and garment type on measured interface pressure in sports compression clothing

The purpose of this investigation was to measure the interface pressure exerted by lower body sports compression garments, in order to assess the effect of garment type, size and posture in athletes. Twelve national-level boxers were fitted with sports compression garments (tights and leggings), each in three different sizes (undersized, recommended size and oversized). Interface pressure was assessed across six landmarks on the lower limb (ranging from medial malleolus to upper thigh) as athletes assumed sitting, standing and supine postures. Sports compression leggings exerted a significantly higher mean pressure than sports compression tights (P < 0.001). Oversized tights applied significantly less pressure than manufacturer-recommended size or undersized tights (P < 0.001), yet no significant differences were apparent between different-sized leggings. Standing posture resulted in significantly higher mean pressure application than a seated posture for both tights and leggings (P < 0.001 and P = 0.002, respectively). Pressure was different across landmarks, with analyses revealing a pressure profile that was neither strictly graduated nor progressive in nature. The pressure applied by sports compression garments is significantly affected by garment type, size and posture assumed by the wearer.     

身体活动的认知效益：量效关系研究及其启示

身体活动已成为延缓老年人认知老化、提高青少年认知功能、改善学生学习等的重要因素,然而基于特定认知效益的锻炼处方设计仍需探索。研究分别从单次身体活动和长期身体活动角度探讨身体活动强度、身体活动时间、身体活动频率、身体活动总量、身体活动类型与认知效益之间的量效关系。在此基础上,提出未来研究应该重点考虑身体活动4个要素的整体设计、考虑不同身体活动项目的认知效益、考察不同人群身体活动的认知效益、考察身体活动认知效益量效关系的机制等,进而为制定促进认知效益的身体活动方案提供循证依据。     

不同运动及特殊环境下运动对脑血流影响的研究述评

综述了有关不同强度和形式的运动,以及特殊环境下运动对脑血流和脑自动调节影响的研究。结果说明中小强度的运动可引起脑血流速度的升高,而高强度运动则使其降低。与动力性运动不同,静力性运动不改变脑血流速度。运动中血流的改变与交感激活引起的血管舒缩和二氧化碳改变有关。通常脑血流自动调节能力不因运动而改变,但力竭运动可使之减弱。热环境下运动时脑血流速度加快以增加散热,但高热下运动时脑血流速度会因过度通气而下降,从而使脑内热积聚,导致疲劳。低氧环境下运动时脑血流速度明显加快以保证大脑足够的氧供,但急性低氧暴露可抑制运动对脑血流的增加效应。     

登山锻炼对小学三年级学生身体素质影响的研究

登山锻炼作为当下较为流行的户外有氧健身运动,其健康价值越来越受到人们的重视。选取湖南省长沙市岳麓区岳南路小学三年级113名学生作为实验对象,分为实验组和对照组,实验组56名同学,对照组57名同学。对实验组进行为期一学年,每周两次的登山训练,对照组则进行常规体育课锻炼。一学年后比较分析两组学生各身体指标的变化及差异,探析登山锻炼对小学三年级学生身体素质的影响。研究表明,登山锻炼对于改善和提高小学三年级学生的心肺功能有明显作用,对小学三年级学生的身体形态、速度素质也能带来积极影响。     

Intensity of exercise recovery,blood lactate disappearance,and subsequent swimming performance

Abstract

The aim of this study was to examine the effects of active versus passive recovery on blood lactate disappearance and subsequent maximal performance in competitive swimmers. Fourteen male swimmers from the University of Virginia swim team (mean age 20.3 years, s = 4.1; stature 1.85 m, s = 2.2; body mass 81.1 kg, s = 5.6) completed a lactate profiling session during which the speed at the lactate threshold (V_LT), the speed at 50% of the lactate threshold (V_LT.5), and the speed at 150% of the lactate threshold (V_LT1.5) were determined. Participants also completed four randomly assigned experimental sessions that consisted of a 200-yard maximal-effort swim followed by 10 min of recovery (passive, V_LT.5, V_LT, V_LT1.5) and a subsequent 200-yard maximal effort swim. All active recovery sessions resulted in greater lactate disappearance than passive recovery (P < 0.0001 for all comparisons), with the greatest lactate disappearance associated with recovery at V_LT (P = 0.006 and 0.007 vs. V_LT.5 and V_LT1.5 respectively) [blood lactate disappearance was 2.1 mmol · l^?1 (s = 2.0), 6.0 mmol · l^?1 (s = 2.6), 8.5 mmol · l^?1 (s = 1.8), and 6.1 mmol · l^?1 (s = 2.5) for passive, V_LT.5, V_LT, and V_LT1.5 respectively]. Active recovery at V_LT and V_LT1.5 resulted in faster performance on time trial 2 than passive recovery (P = 0.005 and 0.03 respectively); however, only active recovery at V_LT resulted in improved performance on time trial 2 (TT₂) relative to time trial 1 (TT₁) [TT₂?TT₁: passive +1.32 s (s = 0.64), V_LT.5+1.01 s (s = 0.53), V_LT?1.67 s (s = 0.26), V_LT1.5?0.07 s (s = 0.51); P < 0.0001 for V_LT). In conclusion, active recovery at the speed associated with the lactate threshold resulted in the greatest lactate disappearance and in improved subsequent performance in all 14 swimmers. Our results suggest that coaches should consider incorporating recovery at the speed at the lactate threshold during competition and perhaps during hard training sessions.     

规律运动与性别差异对高中生身体意象的影响

选用多维度身体与自我关系问卷作工具,对浙江省4所高级中学进行调查.结果显示:(1)除外表取向和疾病取向外,性别差异对高中生的身体意象其他各维度都具有显著影响.男生的外表评价、体能评价、健康评价、身体各部位满意度、体能关注、健康关注显著高于女生.(2)除对头发的满意度无显著性别差异外,对其他身体部位的满意度,男生显著高于女生.(3)规律运动对外表评价、体能评价、健康评价和体能取向有显著影响,而对其他身体意向构成维度没有显著影响.     

Effects of pomegranate extract on blood flow and vessel diameter after high-intensity exercise in young,healthy adults

The effects of pomegranate extract (PE) supplementation were evaluated on high-intensity exercise performance, blood flow, vessel diameter, oxygen saturation (SPO₂), heart rate (HR), and blood pressure (BP). In a randomized, crossover design, nineteen recreationally resistance-trained participants were randomly assigned to PE (1000?mg) or placebo (PL), which were consumed 30?min prior to a repeated sprint ability (RSA) test and repetitions to fatigue (RTF) on bench and leg press. The RSA consisted of ten six-second sprints on a friction-loaded cycle ergometer with 30?s recovery. Brachial artery blood flow and vessel diameter were assessed by ultrasound. Blood flow, vessel diameter, SPO₂, HR, and BP were assessed at baseline, 30?min post ingestion, immediately post exercise (IPost), and 30?min post exercise (30minPost). With PE, blood flow significantly increased IPost RSA (mean difference?=?18.49?mL?min^?1; P?<?.05), and IPost and 30minPost RTF (P?<?.05) according to confidence intervals (CI). Vessel diameter increased significantly 30minPost RSA according to CI and resulted in a significant interaction IPost and 30minPost RTF (P?<?.05). With PE, according to CI, average and peak power output increased significantly in sprint 5 of the RSA (P?<?.05). There was no significant difference between PE and PL for bench (P?=?.25) or leg press (P?=?.15) repetitions. Acute PE supplementation enhanced vessel diameter and blood flow, suggesting possible exercise performance enhancement from increased delivery of substrates and oxygen. The acute timing and capsule form of PE may be advantageous to athletic populations due to ergogenic effects, taste, and convenience.     

膳食脂肪对运动能力的影响及运动时脂代谢的调节

就膳食脂肪对运动能力的影响以及脂肪代谢的调节作一综述。运动强度、时间不同，脂肪供能所占的比例不同，脂肪供能对运动成绩的影响也有所差异。运动时脂代谢的调节受多种因素的影响，激素敏感性甘油三酯脂肪酶(HSL)是酶解速度的主要控制因素。     

Influence of cold-water immersion on limb blood flow after resistance exercise*

This study determined the influence of cold (8°C) and cool (22°C) water immersion on lower limb and cutaneous blood flow following resistance exercise. Twelve males completed 4 sets of 10-repetition maximum squat exercise and were then immersed, semi-reclined, into 8°C or 22°C water for 10-min, or rested in a seated position (control) in a randomized order on different days. Rectal and thigh skin temperature, muscle temperature, thigh and calf skin blood flow and superficial femoral artery blood flow were measured before and after immersion. Indices of vascular conductance were calculated (flux and blood flow/mean arterial pressure). The colder water reduced thigh skin temperature and deep muscle temperature to the greatest extent (P?<?.001). Reductions in rectal temperature were similar (0.2–0.4°C) in all three trials (P?=?.69). Femoral artery conductance was similar after immersion in both cooling conditions, with both conditions significantly lower (55%) than the control post-immersion (P?<?.01). Similarly, there was greater thigh and calf cutaneous vasoconstriction (40–50%) after immersion in both cooling conditions, relative to the control (P?<?.01), with no difference between cooling conditions. These findings suggest that cold and cool water similarly reduce femoral artery and cutaneous blood flow responses but not muscle temperature following resistance exercise.     

对我国东西部城市居民体育锻炼现状的调查与分析

采用问卷调查和数理统计方法，对我国东西部城市居民参加体育锻炼的意识、内容、场所、消费、健身方式及制约因素等方面的情况进行对比研究。结果表明：我国东西部城市居民在健身意识、体育价值观、健身项目的取向、健身方式及活动场所的选择方面具有显著性差异，体育消费水平随经济地位及市民的收入水平而提高。     

浙江大学附属医院群众体育现状分析及对策

采用问卷调查等方法,对浙江大学医学院5所附属医院450名职工进行调查.结果表明:医院职工的体育人口比例为16 8%;锻炼场地以住宅附近为主;锻炼内容登山、跑步居于前二位;锻炼消费每月50元以上的职工比例达20 3%;医院职工对单位组织的全民健身活动满意率达69 1%.建议:重视目标制定和结果考核;聘请社会体育指导员与培训群众体育骨干相结合;以不同强度的锻炼内容满足不同群体的健身需求.     

论大众健身操与都市体育文化建设

通过对大众健身操在都市开展的意义和现状的分析,提出只有建立大众健身操网络,加快培训社会专业指导员的步伐,积极采取措施、创造条件、开发场所,同时加强与大学的区域合作,以奥运会为契机,努力营造大众健身操的化氛围,才能有利于加强都市大众健身操化的建设与管理。     

锻炼对脑老化的影响及其机制

当前我国老年人口快速增长,老年人是人口中的脆弱年龄群体,其大脑机能衰退,认知功能下降、老年痴呆的发病率也在逐年升高。因此,如何保持老年人认知和脑功能已成为近年心理学研究的重要问题。已有的行为研究表明,锻炼可以减缓老年人的认知功能衰退,提高执行功能;近年大量的脑影像研究发现,锻炼对老年人的大脑的结构和功能也有着可塑性影响。回顾了相关的研究进展,讨论了已有研究存在的不足,并提出未来相关研究需要深入探讨的问题。     

Perceptual and cognitive responses during exercise: Relationships with metamotivational state and dominance

Abstract

In this study, we examined ratings of perceived exertion (RPE) and attentional focus during exercise in relation to telic and paratelic metamotivational dominance and state. Thirty regular exercisers (11 females, 19 males), of whom 10 were telic dominant (mean Paratelic Dominance Scale score=6.2±2.9), 10 paratelic dominant (mean PDS score=23.8±1.4), and 10 non-dominant (mean PDS score=15.4±0.7) completed two exercise trials. In the first trial, the participants completed a maximal ramped exercise test on a motorized treadmill to determine their gas exchange threshold (the speed at which determined exercise intensity of the subsequent trial). Throughout the second trial (a 30-min treadmill run), the participants reported their metamotivational state, RPE, and attentional focus (associative or dissociative) at 5-min intervals. Heart rate was recorded at 3, 8, 13, 18, 23, and 28 min and expired air was analysed for oxygen consumption (VO₂) between 1–3, 6–8, 11–13, 16–18, 21–23, and 26–28 min. There was no main effect of dominance or dominance×time interaction on any variables (P >0.05). Oxygen consumption did not differ between states but RPE was higher in the telic than paratelic state at 25 and 30 min (t ₂₈=2.87, P <0.05; t _26.77=3.88, P <0.05, respectively). Attentional focus was more associative in the telic than paratelic state at 20, 25, and 30 min (t ₂₈=? 3.73, P <0.05; t ₂₈=? 4.85, P <0.01; t ₂₈=? 5.15, P <0.05, respectively) and heart rate was higher at 23 min in the telic state (t ₂₇=3.40, P <0.05). During the latter stages of exercise, the telic metamotivational state, not dominance, was related to a more associative attentional focus and higher RPE. Our results support the use of reversal theory (Apter, 2001) to understand perceptual and cognitive responses during aerobic exercise, but an experimental design in which state is manipulated is needed to examine the effects of metamotivational dominance and state on perceptual and cognitive responses.     

杭州市体育健身娱乐市场供需结构研究

通过对杭州市经营性体育健身娱乐部门的调查 ,初步了解市民的体育消费意识、消费行为以及在现有服务体系内的供需结构特征 ,揭示了资金来源、投资方式、企业性质、服务质量、经营方式、总体发展规划、市场潜力、管理水平、法制建设等方面的不足和问题 ,提出了若干宏观发展策略。     

不同剂量茶多糖补充对运动大鼠心肌、血清自由基代谢的影响

为了解不同剂量茶多糖补充对长期大负荷运动大鼠心肌、血清自由基代谢的影响,本研究通过建立灌服不同剂量茶多糖大鼠的长期大负荷游泳训练实验模型,测定大鼠心肌、血清的丙二醛(MDA)含量,超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)和过氧化氢酶(CAT)的活性。结果表明:与运动组相比,运动+茶多糖Ⅰ组、运动+茶多糖Ⅱ组和运动+茶多糖Ⅲ组心肌、血清的MDA含量明显下降,SOD、GSH-Px和CAT活性明显升高,且运动+茶多糖Ⅰ组与运动组间有极显著性差异(P<0.01),运动+茶多糖Ⅱ组和运动+茶多糖Ⅲ组与运动+茶多糖Ⅰ组间有极显著性差异(P<0.01),运动+茶多糖Ⅲ组与运动+茶多糖Ⅱ组间具有显著性差异(P<0.05),呈现一种剂量依赖性:茶多糖补充剂量越高,MDA下降越明显,SOD、GSH-Px和CAT活性升高越明显。提示茶多糖具有较强的抗自由基损伤和抗脂质过氧化的作用,长期服用茶多糖可以有效地减轻运动产生的内源性自由基对大鼠心血管系统的损伤,对大鼠心血管系统产生有效的保护作用。