Nine male recreational cyclist served as subjects in this experiment which included a control, placebo and caffeine trial. The aim of the experiment was to determine whether a 10 mg.kg-1 dose of caffeine given three hours prior to an incremental cycle ergometer exercise test, for caffeine naive subjects, would increase the time to exhaustion and therefore increase the amount of work undertaken by the cyclists. The cyclists initially worked at 100 watts for three minutes and then increased the workload by 50 watts every three minutes until exhaustion. Blood was drawn at the beginning of the test and every three minutes from an ante-cubital vein and was analysed for blood lactate, glucose and free fatty acids (FFA). Respiratory analysis was also undertaken and heart rate was monitored throughout the test. Subjects in the caffeine trial worked significantly longer and performed more work (p less than 0.05) than they did in either the control or placebo trials. FFA's were also significantly higher in this trial (p less than 0.05) and the lactate threshold was moved to the right as a percentage of the VO2max, which suggests less acidity and a decreased bicarbonate flushing. The respiratory exchange ratio data was significantly lowered (p less than 0.05) during workloads between 250 and 450 watts. No changes were seen in blood glucose or heart rates during the experiment. In conclusion, we feel that a 10 mg.kg-1 dose of caffeine is an ergogenic aid during incremental exercise when it is taken 3-4 hours prior to the exercise in fasting subjects who have diets low in caffeine.

Flinn, S, Herbert, K, Graham, K, and Siegler, JC. Differential effect of metabolic alkalosis and hypoxia on high-intensity cycling performance. J Strength Cond Res 28(10): 2852-2858, 2014-The purpose of this study was to investigate the effects of sodium bicarbonate (NaHCO 3 ) ingestion and acute hypoxic exposure on repeated bouts of high-intensity cycling to task failure. Twelve subjects completed 4 separate intermittent cycling bouts cycling bouts to task failure (120% peak power output for 30-second interspersed with 30-second active recovery) under the following conditions: normoxia (F I O 2 % at 20.93%) alkalosis (NA), normoxia placebo (NP), hypoxia (F I O 2 % at 14.7%) alkalosis (HA), and hypoxia placebo (HP). For the NA and HA trials, the buffer solution (0.3 g$kg 21 of NaHCO 3 ) was dispensed into gelatin capsules and consumed over 90 minutes with 1 L of water. Whole-blood acidbase findings demonstrated metabolic alkalosis in both NA and HA before exercise (HCO 3 2 : 32.8 6 1.8 mmol$L 21 ). Time to task failure was significantly impaired in the hypoxic conditions (NA: 199.1 6 62.3 seconds, NP: 183.8 6 45.0 seconds, HA: 127.8 6 27.9 seconds, HP: 133.3 6 28.7 seconds; p , 0.001; h 2 = 0.7). There was no difference between the HA and HP conditions (p = 0.41); however the 2 normoxic conditions approached significance with the NA condition on average resulting in approximately 15-second improvement in time to task failure (p = 0.09). These findings suggest that an acute decline in F I O 2 % consistent with hypoxic exposure is more inhibiting than metabolic acidosis during intermittent highintensity cycling to task failure. In application, the use of hypoxia and NaHCO 3 concurrently to improve performance under these conditions does not seem warranted. Figure 2. Time to task failure (s) for the 4 trial conditions (NA, NP, HA, and HP). Data are presented as mean 6 SD. *Significantly different from hypoxic conditions (p , 0.001). NA = normoxia alkalosis; NP = normoxia placebo; HA = hypoxia alkalosis; HP = hypoxia placebo.Figure 3. Individual performance data represented as responders, nonresponders, and negative responders. Journal of Strength and Conditioning Research the TM | www.nsca.com