Caffeine and Training Intensity Quantification

The goal of this clinical trial is to learn about the effects of caffeine on exercise physiology and the subsequent quantification of athlete training zones in trained cyclists. The main questions that it aims to answer are: * What are the effects of low and moderate doses of caffeine on exercise physiology. * How do the effects of caffeine on exercise physiology affect the calculation of training zones. * Do the effects of caffeine on exercise physiology differ between men and women. Participants will complete four trials on a cycle ergometer as follows: * Trial 1: participants will complete two incremental tests to determine the power outputs required to elicit 50-80% of maximal oxygen consumption for trials 2-4. * Trials 2-4: participants will consume (in a randomized order) either a low (2 mg/kg) dose of caffeine, a moderate (5 mg/kg) dose of caffeine, or a placebo (maltodextrin), 45 minutes prior to to completing an incremental cycling test from 50-80% of maximal oxygen uptake. Measures of heart rate, oxygen uptake, blood lactate, and perceived exertion will be recorded throughout all trials. Researchers will compare the effects of exercise intensity, caffeine dose, and sex to see if they affect exercise physiology and training zone quantification.