What role do different carb sources play in Zone 2 fueling, particularly in regards to performance gains and digestive comfort? For example, do simple carbohydrates like sucrose, glucose, and fructose offer the same benefits as complex carbs such as maltodextrin and amylopectin in this intensity zone?
Are there differences in how the body utilizes these carb sources at moderate intensity versus high intensity, and how does this impact an athletes ability to maintain Zone 2 output over extended periods? Do athletes with higher Zone 2 thresholds or increased aerobic capacity require a different carb profile to maximize their performance?
Additionally, how do individual tolerance to carb sources and gastric emptying rates factor into Zone 2 fueling, and what strategies can athletes use to optimize their carb intake during prolonged exercise in this intensity zone? For instance, does a combination of simple and complex carbs offer the best of both worlds in terms of gastric comfort and energy availability?
Lastly, are there any carb sources that are inherently better than others for Zone 2 fueling, or is the optimal carb profile highly individualized and dependent on an athletes unique physiological response to different carb sources?