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1.
M. A. McNarry M. J. Lewis N. Wade G. A. Davies Con Winn W. T. B. Eddolls 《Journal of sports sciences》2013,31(19):2228-2235
ABSTRACTLittle is known regarding the influence of asthma and exercise, and their interaction, on heart rate variability (HRV) in adolescents.Thirty-one adolescents with asthma (13.7±0.9 years; 21.9±3.9 kg·m?2; 19 boys, 12 girls) and thirty-three healthy adolescents (13.8±0.9 years; 20.3±3.2 kg·m?2; 16 boys, 17 girls) completed an incremental ramp test and three heavy-intensity constant-work-rate cycle tests. Thirteen adolescents (7 boys, 6 girls; 6 asthma, 7 control) completed six-months high-intensity interval training (HIIT) and were compared to age- and sex-matched controls. Standard time-domain, frequency-domain and non-linear indices of HRV were derived at baseline, three- and six-months.Asthma did not influence HRV at baseline or following HIIT. Total power, low frequency and normalised low frequency power, and sympathovagal balance increased at three-months in HIIT, subsequently declining towards baseline at six-months. Normalised high frequency power was reduced at three-months in both groups, which was sustained at six-months. No effects of HIIT were observed in the time-domain nor in the non-linear indices.HRV was not influenced by asthma, potentially because such derangements are a function of disease progression, severity or duration. HIIT may be associated with a short-term shift towards greater sympathetic predominance during exercise, perhaps caused by physiological overload and fatigue. 相似文献
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Inspiratory muscle fatigue may occur in as little as 6 min during high-intensity spontaneously breathing exercise. The aims of this study were to determine whether inspiratory muscle fatigue occurs during swimming exercise and whether inspiratory muscle strength differs between the supine and standing body positions. Seven competitive swimmers were recruited to perform a single 200 m front-crawl swim, corresponding to 90-95% of race pace. Inspiratory muscle strength was measured at residual volume using a hand-held mouth pressure meter that measured maximal inspiratory pressure in the upright and supine positions. At baseline, maximal inspiratory pressure in the supine position was significantly lower than maximal inspiratory pressure in the upright position (112 +/- 20.4 and 133 +/- 16.7 cmH2O, respectively; P < or = 0.01). Post-exercise maximal inspiratory pressure in the supine position (80 +/- 15.7 cmH2O) was significantly lower than baseline maximal inspiratory pressure in the supine position (P < or = 0.01). The results indicate that a single 200 m front-crawl swim corresponding to 90-95% of race pace was sufficient to induce inspiratory muscle fatigue in less than 2.7 min. Furthermore, although diaphragm muscle length is optimized when supine, our results indicate that the force output of the diaphragm and inspiratory accessory muscles is greater when upright than when supine. 相似文献
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Inspiratory muscle fatigue may occur in as little as 6 min during high-intensity spontaneously breathing exercise. The aims of this study were to determine whether inspiratory muscle fatigue occurs during swimming exercise and whether inspiratory muscle strength differs between the supine and standing body positions. Seven competitive swimmers were recruited to perform a single 200 m front-crawl swim, corresponding to 90-95% of race pace. Inspiratory muscle strength was measured at residual volume using a hand-held mouth pressure meter that measured maximal inspiratory pressure in the upright and supine positions. At baseline, maximal inspiratory pressure in the supine position was significantly lower than maximal inspiratory pressure in the upright position (112±20.4 and 133±16.7 cmH2O, respectively; P?0.01). Post-exercise maximal inspiratory pressure in the supine position (80±15.7 cmH2O) was significantly lower than baseline maximal inspiratory pressure in the supine position (P?0.01). The results indicate that a single 200 m front-crawl swim corresponding to 90-95% of race pace was sufficient to induce inspiratory muscle fatigue in less than 2.7 min. Furthermore, although diaphragm muscle length is optimized when supine, our results indicate that the force output of the diaphragm and inspiratory accessory muscles is greater when upright than when supine. 相似文献
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Verheyden B Eijnde BO Beckers F Vanhees L Aubert AE 《Journal of sports sciences》2006,24(11):1137-1147
The purpose of this study was to evaluate the effects of a realistic, feasible, and commonly used fitness training programme on cardiac autonomic control in 14 sedentary men aged 62.0 +/- 6.1 years (mean +/- s). All participants performed a one-year fitness training programme in which training intensity and frequency were specifically chosen to be compliant for the majority of the participants (2-3 sessions per week at moderate intensity). At the same time, a reference group consisting of 15 sedentary age-matched men (age 64.2 +/- 6.5 years) did not change their habitual physical activity. Measurements were performed before and after the training intervention. Cardiac autonomic control was inferred from resting values (supine and standing) of heart rate variability (HRV) computed in the frequency domain over 10-min intervals. Endurance capacity was evaluated during a maximal incremental bicycle ergometer test. In spite of an increase in peak oxygen consumption (VO2peak) by 6.4% after training, heart rate in the training group remained unchanged at rest and at the same metabolic demand. No changes in resting parameters of HRV were shown for either groups or positions. Results from this study provide no evidence of a clinically meaningful increase in the vagal modulation to the sinus node at rest after one year of low-volume and moderate-intensity fitness training in men aged 55-75 years. 相似文献
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This study investigated the changes in urinary neopterin, a biochemical marker of cellular immune activity, in elite male rowers undertaking a progressive increase in training prior to Olympic competition. Twenty‐seven male rowers of the 1992 Great Britain team provided daily urine samples for a 4‐week period of training that included 17 days of altitude training and 10 days of heat acclimatization. The mean (± s.d.) ratio of neopterin/ creatinine in urine increased from pre‐training values of 135 ± 32 to a peak of 219± 121 μmol neopterin per mol creatinine on day 19 of training (P < 0.05). Changes in the ratio of neopterin/creatinine with training were found to be transient and highly variable between subjects, ranging from no change to peak values five‐fold greater than baseline. On the basis of the in vivo measurement of cell‐mediated immunity employed in this study, we conclude that elite athletes engaged in high‐intensity training prior to competition show either no change or a moderate increase in cellular immune activation. 相似文献
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Bart Verheyden Bert O. Eijnde Frank Beckers Luc Vanhees André E. Aubert 《Journal of sports sciences》2013,31(11):1137-1147
Abstract The purpose of this study was to evaluate the effects of a realistic, feasible, and commonly used fitness training programme on cardiac autonomic control in 14 sedentary men aged 62.0 ± 6.1 years (mean ± s). All participants performed a one-year fitness training programme in which training intensity and frequency were specifically chosen to be compliant for the majority of the participants (2 – 3 sessions per week at moderate intensity). At the same time, a reference group consisting of 15 sedentary age-matched men (age 64.2 ± 6.5 years) did not change their habitual physical activity. Measurements were performed before and after the training intervention. Cardiac autonomic control was inferred from resting values (supine and standing) of heart rate variability (HRV) computed in the frequency domain over 10-min intervals. Endurance capacity was evaluated during a maximal incremental bicycle ergometer test. In spite of an increase in peak oxygen consumption ([Vdot]O2peak) by 6.4% after training, heart rate in the training group remained unchanged at rest and at the same metabolic demand. No changes in resting parameters of HRV were shown for either groups or positions. Results from this study provide no evidence of a clinically meaningful increase in the vagal modulation to the sinus node at rest after one year of low-volume and moderate-intensity fitness training in men aged 55 – 75 years. 相似文献
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通过对湿热环境下机体血液成分变化特点的实验,试图揭示湿热环境下运动的身体适应,为训练提供相应的理论依据。随机抽取某大学男生30名,平均年龄(21.3±1.1)岁。实验选择第二军医大学湿热环境训练实验室,环境温度控制在39℃,相对湿度为80%。实验历时9 d,分为测试阶段和训练阶段:测试阶段在训练前、后1 d分别进行12 min功率自行车测试,2次测试前、后经上肢静脉取血(在肛温指标测试后即刻进行);训练阶段周期为7 d,运动负荷为:踏步机徒手踏步15 min,艾威BC4730-52型功率自行车无阻力运动15 min,艾威BC8500型功率自行车调至10LEVEL-280WATT/H运动15 min。结果显示:与第1次、第2次测试前相比,2次测试后血清尿素(BU)、乳酸(La)、[K+]和[Ca2+]均显著升高(P<0.05),[Cl-]显著下降(P<0.05);[Na+]在第2次测试后显著升高(P<0.05)。经过7 d热习服训练,第2次测试前较第1次测试前相比,BU和[Na+]显著升高(P<0.05),La浓度显著下降(P<0.05);第2次测试后同第1次测试后相比,BU、[Na+]、[K+]和[Ca2+]显著升高(P<0.05)。结果表明:经过7 d间断性反复热暴露运动后,机体蛋白质代谢供能有所回降;La清除能力得到提高;血液电解质各项指标发生不同程度变化,但均处于正常生理范围及人体耐受范围内;且运动能力及自我感受得到改善,说明习服训练有利于机体新的热反应动力定型建立。 相似文献
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目的：比较大强度间歇训练（HIIT）和一般有氧训练（AT）2种训练方法的神经-免疫应答特征差异。方法：以8名一线男子皮艇运动员为研究对象,HIIT和AT各进行2周训练,每周9节训练课,训练量基本保持一致;对两种训练方法前、后的测定指标进行比较。分别在HIIT和AT前、后次日晨6：30安静状态下进行仰卧位短时程5 min心率变异性测试,并在测试结束即刻空腹安静状态下取肘静脉血,用于测量淋巴细胞亚群和血浆儿茶酚胺。结果：2周训练后,AT组和HIIT组心率变异性（HRV）时域指标R-R间期标准差（SDNN）、相邻R-R间期差值均方根（RMSSD）、相邻间期的差值标准差（SDSD）和频域指标总功率（TP）、高频功率（HF）、低频功率（LF）均有不同幅度变化,但均无统计学意义,且AT组和HIIT组间无交互效应;AT组T%、CD8+%和HIIT组B%、CD4+%、CD4+/CD8+均有显著差异,且AT组和HIIT组间B%、CD4+%、CD8+%和CD4+/CD8+有显著交互效应;AT组和HIIT组ADR、NE有不同幅度变化,但均无统计学差异;AT组和HIIT组间NE有显著交互效应。结论：与AT相比,HIIT对免疫系统产生影响更大,但两者对神经系统影响均较小。在竞技体育训练过程中,运动员进行HIIT后,建议及时通过饮食、营养品等手段进行干预,避免运动员出现免疫功能下降的现象。 相似文献
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In this study, we investigated heart rate variability in women who exercise regularly, but with differing volumes of physical activity. Forty women participated and were allocated to either a "high" or "moderate" activity group. Heart rate as R-R intervals was recorded during supine rest and analysed using time domain, frequency domain, and Poincaré plot techniques. All time domain and Poincaré analysis measures revealed significant differences in heart rate variability between the "high" and "moderate" activity groups. Frequency domain analysis also revealed a significant difference between the two groups in absolute measures of high-frequency and low-frequency power, but not between measures such as the low-frequency/high-frequency ratio, proposed to represent the sympathetic/parasympathetic balance of cardiac control. The results demonstrate that there is a significant difference in heart rate variability between women who engage in "high" compared with "moderate" volumes of physical activity, which may have implications for cardiac autonomic health. 相似文献
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目的：观察补气补血类中药对女子赛艇运动员冬训期间的生理生化指标变化情况的作用。方法：选择14名17～19岁上海水上运动中心专业赛艇女运动员,随机分为服药组与对照组2组,在冬训开始前休整结束时测的安静指标,服药组在整个冬训期服用补气补血类中药,同时对两组进行与运动训练相关的血生化指标血常规、血尿素氮（BUN）、血清肌酸激酶（CK）、血睾酮（T）、皮质醇（C）的跟踪监测。结果：冬训期后对照组BUN、CK较前都增高,以CK明显（P〈0.05）,而服药组BUN、CK却表现为降低;服药组红细胞（RBC）、红细胞压积（HCT）,血红蛋白（HB）较冬训前均有升高,以HCT及HB升高显著（P〈0.05）;T值服药组较冬训前略升高,而对照组是下降的,C值变化较小,两组无显著差异。结论：补气补血类中药可对女子赛艇运动员冬训期身体机能的恢复有积极的作用,可明显增加其血红蛋白,提高血液携氧能力,从而提高运动能力。 相似文献
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The responses of fatty acid-binding protein and creatine kinase to acute and chronic exercise in junior rowers 总被引：1，自引：0，他引：1
Yuan Y Kwong AW Kaptein WA Fong C Tse M Glatz JF Chan C Renneberg R 《Research quarterly for exercise and sport》2003,74(3):277-283
The responses of fatty acid-binding protein (FABP) and creatine kinase (CK) were compared in a group of junior rowers during 5 weeks of training. Acute exercise induced a larger increase in FABP (70-362%) than in CK (24-156%). When the chronic effect of exercise was studied, the baseline FABP levels were independent of previous training. However, the baseline CK level was dependent on the training that took place during 1 day before (F = 4.362, p < .01) and on the combined training on the previous 2 days (F = 4.606, p < .005). The present results suggest that FABP and CK could be used to monitor acute exercise and chronic exercise, respectively. 相似文献
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Winko W. An Vincy Wong Roy T.H. Cheung 《Sports biomechanics / International Society of Biomechanics in Sports》2013,12(4):375-383
Back injury is common in rowers. Asymmetrical lower limb reaction force on the foot stretchers during rowing may compromise trunk biomechanics and lead to back injury. However, such a mechanism remains putative. Therefore, this study examined lower limb reaction force in experienced rowers with and without a history of back injury. Six rowers who suffered from back injury for more than one week in the past year and another 19 rowers who were never injured performed maximal exertion rowing on a fixed-head rowing machine for 30 strokes. Peak force, average and peak loading rate of the lower limb reaction force during the middle 10-stroke were recorded using strain-gauge transducers placed at the foot stretchers. Asymmetries and intra-limb variability were quantified as asymmetry indices and coefficients of variation, respectively. No significant asymmetry was observed in all selected kinetic parameters between the injured and healthy rowers (p = 0.448–0.722, Hedges' g = 0.162–0.310). Subgroup analyses also did not reveal any significant kinetic differences between injured and healthy scullers or sweepers (p = 0.194–0.855, Hedges' g = 0.203–0.518). Rowers with a history of back injury, regardless of the rowing types, did not demonstrate greater lower limb reaction force asymmetry when compared with healthy rowers. 相似文献
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To compare the effectiveness of training in heat and in sweat clothing in cool conditions on improving heat tolerance, two groups of active subjects (n = 6 in each) performed an interval running heat-tolerance test before and after a 7-day experimental treatment. On each treatment day the subjects attempted to complete 4 x 15 min interval treadmill running periods (a 7.5 s effort every 30 s, on 15 km h-1, 15% grade; the same exercise format as the heat-tolerance test), which were interspersed with 5-min recovery periods (total time each day = 80 min). Group 1 (heat) ran in shorts, socks and shoes in hot humid conditions, and Group 2 (sweat clothing) ran in cool conditions dressed in shorts, socks and T-shirt covered by a polyester-cotton tracksuit, over which was worn 100% nylon spray-proof pants and jacket (cotton lined) with an acrylic cloth bobble hat (beanie) on the head. Both groups displayed changes typical of heat acclimatization over the 7-day period, with significant decreases in final rectal temperature (Tr) and heart rate (HR) being evident, but no change in sweat loss. Mean skin temperature (Tsk) was similar in both groups during the training sessions (heat group: 34.8-35.7 degrees C; sweat clothing group 34.9-35.5 degrees C). After the heat-tolerance test, both groups had significantly lower Tr, Tsk and HR values than before, and sweating sensitivity (g m-2 h-1 degrees C rise in Tr) was significantly increased. There was only one significant difference between the two groups (Tsk, 20th min value). It was concluded that training in sweat clothing in cool conditions can provide the same improvements in heat tolerance as training in hot humid conditions where a fixed exercise intensity and duration are used. 相似文献
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Damien Saboul Pascal Balducci Grégoire Millet Vincent Pialoux Christophe Hautier 《European Journal of Sport Science》2016,16(2):172-181
Recent laboratory studies have suggested that heart rate variability (HRV) may be an appropriate criterion for training load (TL) quantification. The aim of this study was to validate a novel HRV index that may be used to assess TL in field conditions. Eleven well-trained long-distance male runners performed four exercises of different duration and intensity. TL was evaluated using Foster and Banister methods. In addition, HRV measurements were performed 5 minutes before exercise and 5 and 30 minutes after exercise. We calculated HRV index (TLHRV) based on the ratio between HRV decrease during exercise and HRV increase during recovery. HRV decrease during exercise was strongly correlated with exercise intensity (R = ?0.70; p < 0.01) but not with exercise duration or training volume. TLHRV index was correlated with Foster (R = 0.61; p = 0.01) and Banister (R = 0.57; p = 0.01) methods. This study confirms that HRV changes during exercise and recovery phase are affected by both intensity and physiological impact of the exercise. Since the TLHRV formula takes into account the disturbance and the return to homeostatic balance induced by exercise, this new method provides an objective and rational TL index. However, some simplification of the protocol measurement could be envisaged for field use. 相似文献
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The aims of this study were to examine the use of the critical velocity test as a means of predicting 2000-m rowing ergometer performance in female collegiate rowers, and to study the relationship of selected physiological variables on performance times. Thirty-five female collegiate rowers (mean ± s: age 19.3 ± 1.3 years; height 1.70 ± 0.06 m; weight 69.5 ± 7.2 kg) volunteered to participate in the study. Rowers were divided into two categories based on rowing experience: varsity (more than 1 year collegiate experience) and novice (less than 1 year collegiate experience). All rowers performed two continuous graded maximal oxygen consumption tests (familiarization and baseline) to establish maximal oxygen uptake (VO(2max)), peak power output, and power output at ventilatory threshold. Rowers then completed a critical velocity test, consisting of four time-trials at various distances (400 m, 600 m, 800 m, and 1000 m) on two separate days, with 15 min rest between trials. Following the critical velocity test, rowers completed a 2000-m time-trial. Absolute VO(2max) was the strongest predictor of 2000-m performance (r = 0.923) in varsity rowers, with significant correlations also observed for peak power output and critical velocity (r = 0.866 and r = 0.856, respectively). In contrast, critical velocity was the strongest predictor of 2000-m performance in novice rowers (r = 0.733), explaining 54% of the variability in performance. These findings suggest the critical velocity test may be more appropriate for evaluating performance in novice rowers. 相似文献
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本研究旨在探讨特质情绪智力与大学生射箭后即刻心率变异性(HRV)恢复反应的关联性。样本包括34名年龄在18至22岁之间的射箭初学者。第一,这些受试者要完成特质情绪智力量表。第二,他们在四分钟内从18米处向直径为80cm的靶子射出10支箭。第三,在4分钟的恢复期内测量受试者的心率变异性恢复的反应。在本研究中,心率变异性指标采用低频(LF)、高频(HF)和LF/HF比值。结果表明,情绪智力和心率变异性恢复反应之间有显著关系。包含情绪智力子维度的回归模型能够解释HRV频域参数的显著差异。此外,高情绪智力大学生的低频和高频功率高于低情绪智力的大学生,但LF/HF数值低于低情绪智力射箭运动员。综上所述,本研究观察到的结果表明,在严格的射箭训练之后,情绪智力可能会产生更多适应性的HRV恢复反应。 相似文献