Dose effects of caffeine ingestion on acute hormonal responses to resistance exercise

in Sciences Citation Index(SCI), 科學引文索引資料庫(SCI)
標題Dose effects of caffeine ingestion on acute hormonal responses to resistance exercise
出版類型SCI(Sciences Citation Index)
AuthorsWu, 吳柏翰
出版日期2015 / 10

Aim. The purpose of this study was to examine the dose effects
of caffeine on acute hormonal responses to resistance
exercise (RE).
Methods. Twelve university males who regularly performed
RE participated in this study. Subjects performed one repetition
maximum (1RM) test and four treatments in a counterbalanced
order: high dose (HD, 6, medium dose
(MD, 4, low dose (LD, 2, and placebo
(PLA). Subjects ingested caffeine 1 hour before RE and then
performed RE (2 exercises, 3 sets of 10 repetitions at 75% of
1RM). Blood samples were collected before caffeine intake
(pre-60), immediately before RE (pre-exe), and 0, 15, 30 min
post RE (P0, P15, and P30, respectively) for analysis of serum
testosterone, cortisol, insulin, glucose, lactate, and free
fatty acid (FFA). Each experiment was separated by 7 days.
Statistical analysis of two-way analysis of variance with repeated
measures was applied. Statistical significance was set
at α=0.05.
Results. The concentrations of FFA (pre-exe) were significantly
elevated following the HD, MD, and LD ingestions of
caffeine. The concentrations of testosterone (P0, P15, and
P30) and cortisol (pre-exe, P0, P15, and P30) at HD were
significantly increased. However, the responses of insulin (P0
and P15) at HD and MD were significantly decreased.
Conclusion. The results of this study indicate that high doses
of caffeine increase the responses of testosterone and cortisol.
Moreover, moderate and high doses of caffeine attenuate the
insulin responses.

期刊名稱The Journal of Sports Medicine and Physical Fitness
校址:912 屏東縣內埔鄉學府路1號 總機:886-8-7703202 傳真:886-8-7740165 系統開發統維護單位:國立屏東科技大學 電算中心 版權所有