Introduction An important area in the realm of sports nutrition is the timing of food and fluid consumption around exercise. In general, nutrition guidelines for athletes for each of the macronutrients are as follows: 6-10 grams carbohydrate per kilogram body weight per day, 1.2- 1.7 grams protein per kilogram body weight per day, and 20%-30% of total daily energy from fat (Rodriguez et. al 2009). The specific recommendations for each time frame surrounding exercise are detailed below. Before Exercise Eating before exercise has been shown to improve exercise performance when compared to exercising in a fasted state (Maffucci and McMurray 2000, Jentjens et al. 2003, Mosely et al. 2003). In regard to the composition of the pre-exercise meal or snack, it is recommended that it be high in carbohydrates, low in fat, moderate in protein, low in fiber, provide adequate fluid, and be familiar to the athlete (Rodriguez et. al 2009). In general, larger meals can be consumed when there is a greater time gap between eating and exercise, whereas smaller amounts should be consumed if eating and exercise are in close proximity. In terms of carbohydrate, it is recommended that 1-4 grams carbohydrate per kilogram body weight be consumed 1-4 hours prior to exercise (Sugiura and Kobayashi 1998). For fluid needs, at least four hours prior to exercise it is recommended that water or a sports drink be consumed in the amount of approximately 5-7 milliliters per kilogram body weight (Rodriguez et. al 2009).
Transcript
Introduction
An important area in the realm of sports nutrition is the timing of food and fluid consumption around exercise. In general, nutrition guidelines for athletes for each of the macronutrients are as follows: 6-10 grams carbohydrate per kilogram body weight per day, 1.2- 1.7 grams protein per kilogram body weight per day, and 20%-30% of total daily energy from fat (Rodriguez et. al 2009). The specific recommendations for each time frame surrounding exercise are detailed below.
Before Exercise
Eating before exercise has been shown to improve exercise performance when compared to exercising in a fasted state (Maffucci and McMurray 2000, Jentjens et al. 2003, Mosely et al. 2003). In regard to the composition of the pre-exercise meal or snack, it is recommended that it be high in carbohydrates, low in fat, moderate in protein, low in fiber, provide adequate fluid, and be familiar to the athlete (Rodriguez et. al 2009).
In general, larger meals can be consumed when there is a greater time gap between eating and exercise, whereas smaller amounts should be consumed if eating and exercise are in close proximity. In terms of carbohydrate, it is recommended that 1-4 grams carbohydrate per kilogram body weight be consumed 1-4 hours prior to exercise (Sugiura and Kobayashi 1998). For fluid needs, at least four hours prior to exercise it is recommended that water or a sports drink be consumed in the amount of approximately 5-7 milliliters per kilogram body weight (Rodriguez et. al 2009).
The Best Pre-Workout Foods.
Here are the best foods you can eat within an hour before your workout:
Bananas: “They’re nature’s PowerBar,” says Dr. Louise Burke, head of Sports Nutrition at the Australian Institute of Sport and coauthor of The Complete Guide to Food for Sports Performance: Peak Nutrition for Your Sport. Bananas are loaded with digestible carbohydrates and are packed with potassium, which aids in maintaining nerve and muscle function. The body doesn’t store potassium for very long, so a medium banana before a workout will help keep nutrient levels high. Villacorta especially recommends bananas for morning exercisers: “Get up and eat a medium banana with 1/2 cup of Greek yogurt. Wait about 30 minutes and then hit the gym or sport. Your body will need the carbohydrates and protein.”
Oats: Oats are full of fiber, which means they gradually release carbohydrates into your bloodstream, Burke points out. (But they’re not so full of fiber that they’ll cause gas.) This steady stream keeps your energy levels consistent during your workout. Oats also contain B vitamins, which help convert carbohydrates into energy. Help yourself to one cup at least 30 minutes before you begin exercising.
Wholegrain bread: A slice of wholegrain bread is a good source of carbohydrates. “And it has flexible partners,” says Burke. “Top it off with jam or honey for more fuel or sliced up hard-boiled eggs for high-quality protein.” If you’re hitting the gym during your lunch break, grab some bread about 45 minutes before you head out. “Top it with a couple slices of turkey,” suggests Villacorta. “At this time of day, you should eat about 30 grams of carbohydrates and 15 to 20 grams of protein.”
Fruit and Yogurt: Fruit is high in carbohydrates and Greek yogurt is packed with high-quality protein. “People tend to skip fruit and other foods that are high in carbs,” says Villacorta, “but protein doesn’t break down fast enough to become fuel for a workout. The carbs from fruit break down quickly and the protein is used later to prevent muscle damage.” A great morning habit would be to start each day with aFruit and Greek Yogurt Bowl from Jamba Juice.
What to avoid: If you're going to stray from this list, there are a few things you should keep in mind. Be sure to avoid fatty foods before working out—fat leaves the stomach very slowly, which means you’ll feel full and sluggish and could cramp up easily. Although carbohydrates are good, you should not get them from raw sugar or candy. Either of those foods will cause a sugar rush—and probably a crash—while you’re mid-workout. Also, don’t overeat before you workout. These are all snack suggestions, not meals. Eating too much can cause indigestion, sluggishness, nausea and vomiting.
During Exercise
Fueling during exercise is of greatest importance during prolonged exercise. For exercise bouts lasting less than 45-60 minutes, water is generally sufficient. However, endurance performance has been shown to be benefited with drinking sports beverages that contain 6-8% carbohydrate during exercise (Coggan and Coyle 1991, Nicholas et al. 1995, Jeukendrup et al. 1997). For events lasting longer than one hour it is recommended that carbohydrate intake be in the range of 30-60 grams carbohydrate per hour, or 0.7 grams carbohydrate per kilogram body weight per hour (McConell et al. 1996, Currell and Jeukendrup 2008). Carbohydrates may be obtained from food, gels, or sports beverages, the latter option also providing needed fluid.
In regard to fluid intake during exercise, specific general recommendations for fluid replacement during exercise have not been established, as these general guides would likely be inappropriate for many situations (Sawka et al. 2007). Thus, fluid intake should be determined for each athlete individually based on the length of exercise, sweat rate, and opportunities to drink (Rodriguez et. al 2009).
After Exercise
The period immediately following exercise is a time when the body is best positioned to restore glycogen (the storage form of carbohydrates in the body) at the highest rate (Sugiura and Kobayashi 1998). It is recommended that carbohydrates be consumed within 30 minutes after exercise and that 1.5 grams carbohydrate per kilogram be consumed in the first hour following exercise (Ivy et al. 1988, Sugiura and Kobayashi 1998). Adding protein as part of a meal after exercise may be beneficial in regard to muscle protein synthesis and repair (Rodriguez et al. 2007, van Loon et al. 2013). In regard to specific amounts or time frames for protein ingestion surrounding exercise, additional research is needed (van Loon et al. 2013).
If recovery time is not limited, normal meals, snacks, and water intake should be sufficient to replenish fluids lost. In situations where recovery time is limited, or there is excess dehydration, 1.5 liters of fluid for each kilogram of body weight lost should be consumed (Sawka et al. 2007).
Conclusion
When attempting to meet nutrition needs, the timing of eating surrounding exercise is an important consideration. Appropriate meal timing and composition before, during, and after exercise can assist in improving athletic performance.
