Dawson Brian, Vladich Todd, Blanksby Brian A
Department of Human Movement and Exercise Science, The University of Western Australia, Crawley, Western Australia 6009, Australia.
J Strength Cond Res. 2002 Nov;16(4):485-90.
To determine whether 4 weeks of oral creatine (Cr) supplementation could enhance single freestyle sprint and swim bench performance in experienced competitive junior swimmers, 10 young men and 10 young women (x age = 16.4 +/- 1.8 years) participated in a 27-day supplementation period and pre- and posttesting sessions. In session 1 (presupplementation testing), subjects swam one 50-m freestyle and then (after approximately 5 minutes of active recovery) one 100-m freestyle at maximum speed. Blood lactate was measured before and 1 minute after each swim trial. Forty-eight hours later, height, mass, and the sum of 6 skinfolds were recorded, and a Biokinetic Swim Bench total work output test (2 x 30-second trials, with a 10-minute passive recovery in between) was undertaken. After the pretests were completed, participants were divided into 2 groups (n = 10, Cr; and n = 10, placebo) by means of matched pairs on the basis of gender and 50-m swim times. A Cr loading phase of 20 g x d(-1) for 5 days was then instituted, followed by a maintenance phase of 5 g x d(-1) for 22 days. Postsupplementation testing replicated the presupplementation tests. Four weeks of Cr supplementation did not influence single sprint performance in the pool or body mass and composition. However, 30-second swim bench total work scores for trial 1 and trial 2 increased after Cr (p < 0.05) but not placebo ingestion. Postexercise blood lactate values were not different after supplementation for the 50- and 100-m sprint trials either within or between groups. It was concluded that 4 weeks of Cr supplementation did not significantly improve single sprint performance in competitive junior swimmers, but it did enhance swim bench test performance.
为了确定为期4周的口服肌酸（Cr）补充剂是否能够提高有经验的青少年竞技游泳运动员的单次自由泳冲刺和游泳长凳测试成绩，10名年轻男性和10名年轻女性（平均年龄 = 16.4 +/- 1.8岁）参加了为期27天的补充期以及测试前和测试后的环节。在第1阶段（补充前测试），受试者先游一次50米自由泳，然后（在大约5分钟的主动恢复后）以最快速度游一次100米自由泳。在每次游泳测试前和测试后1分钟测量血乳酸。48小时后，记录身高、体重和6处皮褶厚度之和，并进行生物动力学游泳长凳总功输出测试（2次30秒测试，中间有10分钟的被动恢复）。在完成预测试后，根据性别和50米游泳时间通过配对将参与者分为2组（每组n = 10，Cr组和n = 10，安慰剂组）。然后进行为期5天的20克×天⁻¹的肌酸负荷期，随后是为期22天的5克×天⁻¹的维持期。补充后测试重复补充前测试。4周的肌酸补充对泳池中的单次冲刺成绩、体重和身体成分没有影响。然而，在摄入肌酸后，第1次和第2次测试的30秒游泳长凳总功得分有所增加（p < 0.05），但摄入安慰剂后没有增加。在补充后，组内和组间的50米和100米冲刺测试后的运动后血乳酸值没有差异。得出的结论是，4周的肌酸补充并没有显著提高青少年竞技游泳运动员的单次冲刺成绩，但确实提高了游泳长凳测试成绩。
