Department of Health and Kinesiology, Exercise and Sport Nutrition Lab, Texas A&M University, College Station, TX 77843-4243, USA.
J Int Soc Sports Nutr. 2014 Feb 26;11(1):6. doi: 10.1186/1550-2783-11-6.
Extracts of Russian Tarragon (RT) have been reported to produce anti-hyperglycemic effects and influence plasma creatine (Cr) levels while supplementing with creatine monohydrate (CrM). The purpose of this preliminary study was to determine if short-term, low-dose aqueous RT extract ingestion prior to CrM supplementation influences whole body Cr retention, muscle Cr or measures of anaerobic sprint performance.
In a double-blind, randomized, and crossover manner; 10 recreationally trained males (20 ± 2 yrs; 179 ± 9 cm; 91.3 ± 34 kg) ingested 500 mg of aqueous RT extract (Finzelberg, Andernach, Germany) or 500 mg placebo 30-minutes prior to ingesting 5 g of CrM (Creapure®, AlzChem AG, Germany) twice per day for 5-days then repeated after a 6-week wash-out period. Urine was collected at baseline and during each of the 5-days of supplementation to determine urine Cr content. Whole body Cr retention was estimated from urine samples. Muscle biopsies were obtained for determination of muscle free Cr content. Participants also performed two 30-second Wingate anaerobic capacity tests prior to and following supplementation for determination of peak power (PP), mean power (MP), and total work (TW). Data were analysed by repeated measures MANOVA.
Whole body daily Cr retention increased in both groups following supplementation (0.0 ± 0.0; 8.2 ± 1.4, 6.5 ± 2.4, 5.6 ± 3.2, 6.1 ± 2.6, 4.8 ± 3.2 g · d-1; p = 0.001) with no differences observed between groups (p = 0.59). After 3 and 5-days of supplementation, respectively, both supplementation protocols demonstrated a significant increase in muscle free Cr content from baseline (4.8 ± 16.7, 15.5 ± 23.6 mmol · kg-1 DW, p = 0.01) with no significant differences observed between groups (p = 0.34). Absolute change in MP (9 ± 57, 35 ± 57 W; p = 0.031), percent change in MP (2.5 ± 10.5, 6.7 ± 10.4%; p = 0.026), absolute change in TW (275 ± 1,700, 1,031 ± 1,721 J; p = 0.032), and percent change in TW (2.5 ± 10.5, 6.6 ± 10.4%; p = 0.027) increased over time in both groups with no differences observed between groups.
Short-term CrM supplementation (10 g · d-1 for 5-days) significantly increased whole body Cr retention and muscle free Cr content. However, ingesting 500 mg of RT 30-min prior to CrM supplementation did not affect whole body Cr retention, muscle free Cr content, or anaerobic sprint capacity in comparison to ingesting CrM with a placebo.
据报道,俄式春黄菊(RT)提取物具有抗高血糖作用,并影响补充肌酸单水合物(CrM)时的血浆肌酸(Cr)水平。本初步研究的目的是确定短期、低剂量水提 RT 提取物在补充 CrM 之前摄入是否会影响全身 Cr 保留、肌肉 Cr 或无氧冲刺性能的测量。
采用双盲、随机、交叉方式;10 名有经验的男性(20±2 岁;179±9cm;91.3±34kg)分别在摄入 5g CrM(Creapure®,AlzChem AG,德国)之前 30 分钟内摄入 500mg 水提 RT 提取物(Finzelberg,Andernach,德国)或 500mg 安慰剂,每天两次,持续 5 天,然后在 6 周洗脱期后重复。在基线和补充的 5 天中的每一天收集尿液,以确定尿液 Cr 含量。全身 Cr 保留量根据尿液样本估算。肌肉活检用于测定肌肉游离 Cr 含量。参与者还在补充前后进行了两次 30 秒的 Wingate 无氧能力测试,以确定峰值功率(PP)、平均功率(MP)和总功(TW)。数据通过重复测量 MANOVA 进行分析。
两组在补充后全身每日 Cr 保留量均增加(0.0±0.0;8.2±1.4、6.5±2.4、5.6±3.2、6.1±2.6、4.8±3.2g·d-1;p=0.001),但组间无差异(p=0.59)。分别在补充 3 天和 5 天后,两种补充方案均显示肌肉游离 Cr 含量相对于基线显著增加(4.8±16.7、15.5±23.6mmol·kg-1 DW,p=0.01),但组间无显著差异(p=0.34)。MP 的绝对变化(9±57、35±57W;p=0.031)、MP 的百分比变化(2.5±10.5、6.7±10.4%;p=0.026)、TW 的绝对变化(275±1、1700、1031±1、721J;p=0.032)和 TW 的百分比变化(2.5±10.5、6.6±10.4%;p=0.027)在两组中均随时间增加,组间无差异。
短期 CrM 补充(5 天每天 10g)显著增加全身 Cr 保留和肌肉游离 Cr 含量。然而,与服用 CrM 安慰剂相比,在服用 CrM 之前摄入 500mg RT 并不会影响全身 Cr 保留、肌肉游离 Cr 含量或无氧冲刺能力。