Warmup has been a general practice for most athletes to engage in prior to a practice or competitive race. However, there has been little scientific evidence, specifically for the endurance athlete concerning the appropriate duration, intensity, or a combination of duration and intensity needed to enhance performance. Therefore, the purpose of this study was to determine how different combinations of durations and intensities of warmup affect heart rate (HR), lactic acid· (LA), minute ventilation (VE), respiratory exchange ratio (R) and rating of perceived exertion (RPE) during a 5 minute treadmill run at 80% VO2 max. Subjects included four male and four female trained (male mean VO2 max= 55.3; female mean vo2 max= 48.6) endurance athletes (mean age= 30.6 yr, SD=+ 4.4). Subjects randomly participated in one of the warmup conditions, followed by a 5 minute run at 80% vo2 max. The four warmup conditions were low intensity, short duration (LISD), low intensity, long duration (LILD), high intensity, short duration (HISD) and high intensity, long duration (HILD}. The low and high intensities were set at 40% vo2 max and 80% VO2 max, and the short and long durations were set at 5 and 20 minutes, respectively. Results of the 2 x 2 ANOVA showed significant (p\u3c.01) main effects for duration for RPE, with 20 minutes significantly higher than 5 minutes, and intensity for HR (p\u3c.01), with 70% VO2 max significantly greater than 40% vo2 max. There was no significance found for LA, Rand VE. The omega squared analysis showed that for RPE and HR 68.7% and 39.6% of the variance among the conditions was due to the duration and intensity of the warrnup, respectively. In summary, no particular warrnup produced optimal effects on all of the physiological factors associated with performance. Therefore, it is recommended that warrnup within the range of 40% to 70% V02 max for 5 or 20 minutes produced equivalent effects for most of the physiological variables studied
