运动前饮料（PRX）对与最大有氧能力相关因素的影响。
The influence of a pre-exercise sports drink (PRX) on factors related to maximal aerobic performance.
机构信息
Department of Kinesiology, Angelo State University, San Angelo, TX 76909, USA.
出版信息
J Int Soc Sports Nutr. 2010 Mar 11;7:12. doi: 10.1186/1550-2783-7-12.
BACKGROUND
Pre-exercise sports drinks (PRX) are commonly used as ergogenic aids in athletic competitions requiring aerobic power. However, in most cases, claims regarding their effectiveness have not been substantiated. In addition, the ingredients in PRX products must be deemed acceptable by the athletic governing bodies that regulate their use in training and competition. The purpose of this study was to examine the effects of a modified PRX formulation (known as EM.PACT) from earlier investigations on factors related to maximal aerobic performance during a graded exercise test. The modification consisted of removing creatine to meet the compliance standards set forth by various athletic organizations that regulate the use of nutritional supplements.
METHODS
Twenty-nine male and female college students varying in levels of aerobic fitness participated in a randomized crossover administration of PRX (containing 14 g/serving of fructose, medium-chain triglycerides, and amino acids mixed with 8 oz. of water) and placebo (PL) 30 minutes prior to performing a treadmill test with approximately one week separation between the trials. VO2max, maximal heart rate (HR), time to exhaustion (Time), and percentage estimated non-protein fat substrate utilization (FA) during two a priori submaximal stages of a graded exercise testing were evaluated.
RESULTS
The VO2max mean value of the PRX trial was significantly greater than the PL trial (P < 0.01). The mean value for Time was also observed to be greater for the PRX trial compared to PL (P < 0.05). Additionally, percentage of FA during submaximal stages of the exercise test was greater for PRX trial in comparison to PL (P < 0.01).
CONCLUSIONS
The modified PRX formulation utilized in this investigation supports the findings of the previous investigation and its efficacy for enhancing indices of aerobic performance (specifically VO2max, Time, & FA) during graded exercise testing.
背景
运动前饮料（PRX）通常被用作需要有氧能力的竞技比赛中的助益剂。然而，在大多数情况下，关于它们有效性的说法尚未得到证实。此外，PRX 产品中的成分必须被管理其在训练和比赛中使用的运动管理机构认为是可接受的。本研究的目的是检查早期研究中改良 PRX 配方（称为 EM.PACT）对与分级运动测试中最大有氧表现相关的因素的影响。这种修改包括去除肌酸，以符合管理营养补充剂使用的各种运动组织制定的合规标准。
方法
29 名男女大学生，有氧健身水平不同，参加了 PRX（每份含 14 克果糖、中链甘油三酯和氨基酸，与 8 盎司水混合）和安慰剂（PL）的随机交叉给药，两者之间相隔约一周时间进行跑步机测试。评估两次试验之间约一周的两次预先设定的次最大分级运动测试中的最大摄氧量（VO2max）、最大心率（HR）、衰竭时间（Time）和估计非蛋白质脂肪底物利用率（FA）的百分比。
结果
PRX 试验的 VO2max 平均值明显大于 PL 试验（P<0.01）。PRX 试验的 Time 平均值也大于 PL（P<0.05）。此外，与 PL 相比，PRX 试验在运动测试的次最大阶段的 FA 百分比更高（P<0.01）。
结论
本研究中使用的改良 PRX 配方支持了之前研究的发现，并且对增强分级运动测试中的有氧表现（特别是 VO2max、Time 和 FA）的功效。
Zotero 插件