To date, no one has examined the concurrent effects of Cr supplementation and HIIT. Therefore, we propose that Cr supplementation may increase training capacity during HIIT, resulting in improved endurance performance as measured by VO2PEAK, VT, and TTE, beyond what has been demonstrated for HIIT alone. The purpose of this study was to learn more determine the combined effects of four weeks of HIIT and Cr supplementation on VO2PEAK, VT, and TTE in recreationally active college-aged men. Methods Forty-three recreationally active (1-5 hours of regimented exercise per week) college-aged men (mean ± SD, Age: 22.6 ± 4.9 years; Ht: 178.1 ± 7.1 cm; Wt: 83.0 ± 13.8 kg) volunteered to participate

in this study. Participants were screened for health conditions that would have prevented them https://www.selleckchem.com/products/azd2014.html from participating in the study, including heart and joint conditions. Any participants who had taken sports supplements, including any form of Creatine, in the three months prior to the beginning of the study were excluded. Participants kept a food diary, and none of the participants consumed a vegetarian diet. Participants were asked selleckchem not to change training or dietary habits for the duration of the study. This study was approved by the University’s Institutional Review Board for Human Subjects and informed consent was obtained from each participant prior to enrollment. Determination of VO2PEAK, ventilatory threshold, and total work done A maximal graded exercise test (GXT) on a cycle ergometer

(Corival 400, Groningen, The Netherlands) was completed by all participants to determine maximal oxygen consumption (VO2PEAK). Participants began pedaling at a cadence of 60-80 revolutions per minute (RPM) at a workload of 20 watts (W). The workload increased 1 W every 3 seconds (a total of 20 W every minute). This continued until the subject could no longer maintain 60-80 RPM or until volitional exhaustion, O-methylated flavonoid despite verbal encouragement. Respiratory gases were monitored and continuously analyzed with open-circuit spirometry using a calibrated metabolic cart (True One 2400®, Parvo-Medics, Inc., Provo, UT). Data were averaged over 15-second intervals, with the highest 15-second oxygen consumption and heart rate recorded as the peak oxygen consumption (VO2PEAK) and maximum heart rate (HRmax), respectively. Time to exhaustion for the GXT (VO2PEAKTTE) was recorded. In addition, ventilatory threshold (VT) was measured during this test. VT was determined from a plot of ventilation (VE) against VO2 as described previously [20]. Two linear regression lines were fit to the lower and upper portions of the VE vs. VO2 curve, before and after the break points, respectively. The intersection of these two lines was defined as VT.