Rahimi Rahman
Department of Exercise Physiology, University of Kurdistan, Sanandaj, Kurdistan, 416, Islamic Republic of Iran.
Ir J Med Sci. 2019 Feb;188(1):337-345. doi: 10.1007/s11845-018-1780-7. Epub 2018 Mar 12.
The purpose of this study was to examine the effect of CYP1A2 -163C>A polymorphism on the ergogenic effects of caffeine supplementation during a resistance exercise (RE) session.
In a randomized, double-blind, placebo (PL)-controlled, crossover study, 30 resistance-trained men took part in two RE sessions (three sets to failure at 85% of one repetition maximum, 2-min rest between sets), including bench press (BP), leg press (LP), seated cable row, and shoulder press (SP) following caffeine (CAF) (6 mg kg) or PL (6 mg kg of maltodextrin) ingestion 1 h prior to the trial. The number of repetitions was recorded after each set, along with calculation of total number of repetitions for each exercise. Genomic DNA was isolated from the whole blood samples for analyzing the CYP1A2 -163C>A polymorphism through amplification refractory mutation system-polymerase chain reaction (ARMS-PCR). Subjects were classified as either AA (n = 14) or AC/CC genotypes (n = 16).
The two-way ANOVA with repeated measures revealed differences between AAs and AC/CCs under CAF conditions for repetitions performed in sets 1, 2, and 3 of BP (F = 14.84, P = 0.001, ƞ = 0.34), LP (F = 8.92, P = 0.006, ƞ = 0.24), SR (F = 17.38, P = 0.0001, ƞ = 0.38), and SP (F = 3.76, P = 0.063, ƞ = 0.11). CAF also increased the total number of repetitions performed for all three sets in AAs versus AC/CCs for BP (F = 8.72, P = 0.006, ƞ = 0.23), LP (F = 4.67, P = 0.03, ƞ = 0.14), SR (F = 5.54, P = 0.02, ƞ = 0.16), and SP (F = 3.89, P = 0.058, ƞ = 0.12) in athletes who were homozygous carriers of the A allele, compared to the C allele carriers. Therefore, AA homozygotes were able to carry out a greater total volume of RE work under CAF but not PL conditions, compared to the C allele carriers.
In conclusion, acute ingestion of CAF significantly enhanced RE performance in resistance-trained men who were homozygous for the A allele, but not for C allele carriers. Further studies are needed to replicate the potential role of the CYP1A2 -163C>A polymorphism on the ergogenic effects of CAF in other modes of exercise and in other populations.
本研究旨在探讨CYP1A2 -163C>A基因多态性对阻力训练（RE）期间补充咖啡因的促力效果的影响。
在一项随机、双盲、安慰剂（PL）对照的交叉研究中，30名进行过阻力训练的男性参加了两次RE训练（以一次重复最大值的85%进行三组至力竭，组间休息2分钟），包括卧推（BP）、腿举（LP）、坐姿绳索划船和肩推（SP），在试验前1小时摄入咖啡因（CAF）（6毫克/千克）或PL（6毫克/千克麦芽糖糊精）。每组训练后记录重复次数，并计算每项运动的总重复次数。从全血样本中提取基因组DNA，通过扩增阻滞突变系统-聚合酶链反应（ARMS-PCR）分析CYP1A2 -163C>A基因多态性。受试者被分为AA基因型（n = 14）或AC/CC基因型（n = 16）。
重复测量的双向方差分析显示，在CAF条件下，AA基因型和AC/CC基因型在BP训练的第1、2和3组的重复次数上存在差异（F = 14.84，P = 0.001，ƞ = 0.34），LP训练（F = 8.92，P = 0.006，ƞ = 0.24），坐姿绳索划船（SR）训练（F = 17.38，P = 0.0001，ƞ = 0.38）和SP训练（F = 3.76，P = 0.063，ƞ = 0.11）。与C等位基因携带者相比，CAF还增加了AA基因型受试者在BP训练（F = 8.72，P = 0.006，ƞ = 0.23）、LP训练（F = 4.67，P = 0.03，ƞ = 0.14）、SR训练（F = 5.54，P = 0.02，ƞ = 0.16）和SP训练（F = 3.89，P = 0.058，ƞ = 0.12）中三组训练的总重复次数。因此，与C等位基因携带者相比，AA纯合子在CAF而非PL条件下能够完成更大总量的RE训练。
总之，急性摄入CAF可显著提高A等位基因纯合的阻力训练男性的RE表现，但对C等位基因携带者则无此效果。需要进一步研究以验证CYP1A2 -163C>A基因多态性在其他运动模式和其他人群中对CAF促力效果的潜在作用。
