J Sports Med Phys Fitness: Caffeine doesn't change serum testosterone levels during men's exercise

This study investigated the effect of caffeine supplementary (CAF) coffee intake on the exercise response of serum testosterone (T) in men trained in exercise intensitysubjects consumed 12 ounces of coffee (CAF) through random, cross-object cross-design before exercise, supplemented with water-free or decaffeinated (DEC) coffee, and consumed 6 mg / kg of caffeineThe exercise process consists of 21 minutes of high-intensity intermittent circulation (2 minutes with 2.0 mmol / L lactic acid and 4.0 mmol / L lactic acid 1 minute alternate power output strength), followed by resistance exercise (seven exercises, three groups, 10 repetitions per group, 65% 1RM, one minute of rest time)The subjects also completed fatigue tests and repeated tests of soreness levels to determine muscle recovery 24 hours after exerciseresults showed that T increased by 20.5 percent and 14.3 percent (P 0.05) in the immediate and 30 minutes after exerciseTreatment had no major effect and there was no interaction between exercise and treatmentThere was no difference in repetition of fatigue or soreness between the two treatments (P0.05)There is no relationship between T and any recovery metrics, the results show that although past literature has shown that caffeine can enhance post-exercise T, the data from current studies suggest that the increase in T-reactions after the addition of waterless caffeine in coffee was not significantThe duration of the elevated T indicates that the programme is beneficial to the long-term increase of serum testosterone