A good carbohydrate is not limited to brown rice, and a fast-digesting food is not automatically bad. Quality, portion, timing, and digestive tolerance determine the best choice. Potatoes and oats may suit one meal, while fruit or white rice may be easier near training.
The short answer
For most meals, whole grains, legumes, fruit, starchy vegetables, and plain dairy are useful choices. Closer to exercise or during long events, lower-fiber, easier-to-digest carbohydrate can be appropriate.
Strong everyday choices
Oats, whole-grain bread, rice, potatoes, sweet potatoes, corn, legumes, fruit, and vegetables provide useful variety. Less-processed choices often add fiber and micronutrients, but every carbohydrate serving does not need to be whole grain.
Choices around training
When a meal is only one to two hours before exercise, very high fiber or fat can cause discomfort. Rice, bread, banana, potatoes, or yogurt with fruit may be easier depending on individual tolerance.
Added sugar and sweet drinks
Added sugar can occupy a small place in the diet but should not displace fiber-rich, nutrient-dense foods. Sports drinks have a role in prolonged exercise; routine use for a short workout is usually unnecessary.
Practical tips
Match the carbohydrate source to the purpose of the meal.
Obtain more daily fiber in meals farther from training.
Track digestion and performance responses.
Bottom line
Numbers are starting points, not verdicts. The right choice must fit goals, calories, training quality, digestion, and real trends. Make small changes and assess them over several weeks.
References
WHO — Carbohydrate Intake for Adults and Children — https://www.who.int/publications/i/item/9789240073593
Academy of Nutrition and Dietetics, Dietitians of Canada and ACSM — Nutrition and Athletic Performance — https://pubmed.ncbi.nlm.nih.gov/26920240/
ISSN Position Stand: Nutrient Timing — https://pubmed.ncbi.nlm.nih.gov/28919842/