Although your strength and general fitness level have a major effect on your exercise performance, nutrition also plays a major role. Consuming the right types of food before your workouts or competitions provide the energy needed to perform at a high level of competition. Carbohydrates are often suggested for pre-exercise nutrition, but you should note that not all carbohydrates are the same, and some may have detrimental effects on performance 12.

Complex Carbohydrates

Complex carbohydrates are found in vegetables, whole grains and other food sources that are not highly refined or processed. Your body needs to expend more effort to process complex carbohydrates, so they are absorbed more slowly than simple carbohydrates. As a result, complex carbohydrates can keep your energy levels stable, which is preferable for exercise. Research indicates that complex carbohydrates can improve endurance more than simple carbohydrates.

Simple Carbohydrates

Simple carbohydrates are also known as simple sugars and include refined foods such as candy and other high-sugar, processed foods. Simple carbohydrates are absorbed quickly by your body, but do not provide sustained energy. Simple carbohydrates sometimes result in a crash, or feelings of fatigue, and may cause cramps or stomach discomfort when consumed before exercise.

Timing

In addition to choosing the right kinds of carbohydrates, carefully consider the timing of your pre-workout carbs. If you don't provide enough time between your meal and exercise, your meal may not be fully digested, resulting in discomfort. Consume a small meal 2 to 3 hours prior to exercise.

Pre-Exercise Meals

A variety of pre-exercise meals may benefit your performance. Sports nutritionist Molly Kimball, R.D., suggests combining milk, fresh fruit and protein powder in a shake to help prevent protein breakdown during your workout. You can add whole grains such as oats or cereal for complex carbs. A solid meal should combine protein and carbohydrates -- try a bagel sandwich or pair chicken with a potato. Limit fatty foods before exercise, so avoid pizza, burgers and fried food.