Effect of whole-body contrast-water therapy on recovery from intense exercise of short duration

Abstract

Athletes often use contrast-water therapy as a recovery modality to reduce training fatigue. However, there is debate regarding the effectiveness of this practice, particularly when active and passive recovery regimens are more readily accessible. Fourteen male state-level hockey players participated in three experimental sessions involving two 30-s maximal-intensity Wingate ergometer tests interspersed by a 12-min recovery period. Three different recovery protocols were assessed. Passive recovery involved sitting while active recovery comprised low-intensity cycling. Contrast-water therapy recovery involved three cycles of alternate immersion in heated (38°C) and cool (15°C) water for 3.5 min and 30 s respectively. Heart rate, blood lactate concentration, and ratings of fatigue were assessed immediately before (baseline) and after the first Wingate test, 3 min and 7 min into and at the end of the recovery period, and immediately after the second Wingate test. Blood pressure was assessed at baseline, immediately before recovery, and immediately after recovery. Heart rate remained elevated 3 min and 7 min into as well as after active recovery compared with both contrast-water therapy (P<0.001) and passive recovery (P<0.001), and was elevated 3 min into and after contrast-water therapy recovery compared with passive recovery (P<0.001). Blood lactate concentration was significantly lowered 7 min into and after active recovery (P<0.001) and contrast-water therapy (P<0.001) compared with passive recovery, but no significant difference was observed between active recovery and contrast-water therapy. Rating of fatigue was significantly lower for contrast-water therapy (P<0.001) compared with passive recovery and active recovery, the latter two being similar. However, no significant differences were found between the recovery modalities for any of the test or retest Wingate performance indices. Although contrast-water therapy offered similar benefits to well-established active recovery protocols, it also resulted in reduced ratings of fatigue and a faster return to baseline for some variables. Although restricted to a limited time frame, these findings reflect that the subtle effects from contrast-water therapy may translate to important practical differences that can influence the recovery choices of athletes, particularly when engaged in intense events/training where the recovery period is limited.     

Postexercise Energy Expenditure following Upper Body Exercise

Abstract

This study was designed to examine the magnitude and duration of excess postexercise oxygen consumption (EPOC) following upper body exercise, using lower body exercise for comparison. On separate days and in a counterbalanced order, eight subjects (four male and four female) performed a 20-min exercise at 60% of mode-specific peak oxygen uptake (VO₂) using an arm crank and cycle ergometer. Prior to each exercise, baseline VO₂ and heart rate (HR) were measured during the final 15 min of a 45-min seated rest. VO₂ and HR were measured continuously during the postexercise period until baseline VO₂ was reestablished. No significant difference between the two experimental conditions was found for magnitude of EPOC (t [7] = 0.69, p > .05). Mean (± SD) values were 9.2 ± 3.3 and 10.4 ± 5.8 kcal for the arm crank and cycle ergometer exercises, respectively. Duration of EPOC was relatively short and not significantly different (t [7] = 0.24, p > .05) between the upper body (22.9 ± 13.7 min) and lower body (24.2 ± 19.4 min) exercises. Within the framework of the chosen exercise conditions, these results suggest EPOC may be related primarily to the relative metabolic rate of the active musculature, as opposed to the absolute exercise VO₂ or quantity of active muscle mass associated with these two types of exercise.     

炼油厂瓦斯气回收利用技术

本文通过对某炼油厂低压瓦斯气系统分析研究,增加微压自动控制系统,配合装置操作参数的调整,降低瓦斯气含水,将低压瓦斯气引入加热炉作为燃料,使瓦斯气回收率达到85%,节约了燃料油消耗,降低了操作成本,为中小型炼化企业提供了技术改进方向。     

水中康复操对运动员关节损伤后肢体功能恢复的影响研究

目的：观察水中康复操对运动员关节损伤后肢体功能恢复的效果。方法：将80例在运动中关节损伤的患者随机分为试验组和对照组各40例,两组患者均进行相同的康复操锻炼,试验组在音乐的伴奏下,在深度为1.1-1.5米的水中进行操化锻炼。结果：试验组与对照组的效果对比,试验组总有效率为95%,明显优于对照组80%（P（0.01）。结果：水中康复操的锻炼对运动员关节损伤后肢体功能的恢复有很好的效果。     

男大学生中长跑运动员训练过程生理生化指标研究——心率恢复率、血乳酸清除率变化情况

通过实验室研究方法、文献资料法、数理统计法、综合分析法等研究方法对业余男中长跑运动员在不同训练阶段的血乳酸清除率、心率恢复率等指标进行测定,得出了不同训练阶段运动员的运动强度安排、间歇时间安排应不同的结论.运动员在训练初期运动强度要小些,间歇时间为9min左右;训练三个月后训练强度可适当加大,间歇时间调整为8min左右;当系统训练半年后由于运动员的血乳酸清除率和心率恢复率都达到了一个较高的水平,可以采用较大的训练强度,适当地缩短训练时间,将间歇时间调整为7min左右.     

现代运动训练理论与实践的新变革

随着比赛日益增多，现代运动训练理论与实践发生了许多新的变革，如训练周期观念更新，更加重视专项训练，训练负荷以强度为主，高度注重恢复训练等。     

Effects of inertia correction and resistive load on fatigue during repeated sprints on a friction-loaded cycle ergometer

Abstract

Seven 6 s sprints with 30 s recovery between sprints were performed against two resistive loads: 50 (L50) and 100 (L100) g · kg^?1 body mass. Inertia-corrected and -uncorrected peak and mean power output were calculated. Corrected peak power output in corresponding sprints and the drop in peak power output relative to sprint 1 were not different in the two conditions, despite the fact that mean power output was 15–20% higher in L100 (P < 0.01). The effect of inertia correction on power output was more pronounced for the lighter load (L50), with uncorrected peak power output in sprint 1 being 42% lower than the corresponding corrected peak power output, while this was only 16% in L100. Fatigue assessed by the drop in uncorrected peak and mean power output in sprint 7 relative to sprint 1 was less compared with that obtained by corrected power values, especially in L50 (drop in uncorrected vs. corrected peak power output: 13.3 ± 2.2% vs. 23.1 ± 4.1%, P < 0.01). However, in L100, the difference between the drop in corrected and uncorrected mean power output in sprint 7 was much smaller (24.2 ± 3.1% and 21.2 ± 2.7%, P < 0.01), indicating that fatigue may be safely assessed even without inertia correction when a heavy load is used. In conclusion, when inertia correction is performed, fatigue during repeated sprints is unaffected by resistive load. When inertia correction is omitted, both power output and the fatigue profile are underestimated by an amount dependent on resistive load. In cases where inertia correction is not possible during a repeated sprints test, a heavy load may be preferable.     

新型体力恢复运动饮料的研制

以乳清蛋白为原料,感官评价为指标,运用科学配方生产体力恢复运动保健饮料,通过单因素和正交实验确定了饮料的最佳配方：乳清蛋白添加量3．0％,混合甜味剂添加量3％,混合酸味剂添加量1．5％,食盐为1．2％、维生素C为2．5％。所得产品口感良好,品质稳定。     

力量训练的营养恢复

科学合理的营养补充是运动员取得良好运动成绩的前提条件。通过营养素的使用,使运动员能够跟上训练节奏,较好地完成教练员的训练计划。通过长期的运动训练实践,总结出如何进行力量训练的营养补充,以及达到怎样的恢复效果。有针对性的、合理的营养素（糖、电解质、维生素等）补充,可以帮助运动员加快运动后疲劳的恢复。