When it comes to working out what you eat, when, and how much, can all have an effect on how efficient your exercising is. Fueling your body properly for your next round of physical activity can be a science and this video and article are intended to help clear up some of the questions you have and give you a general understanding of why. Now keep in mind while reading this that our suggestions are based on what would work best for the largest population of typical exercisers. If you are a competitive athlete or have special dietary issues then you might not fall into the population that this is meant for.
Eating before a bout of physical activity falls into two main categories; having access to food, or the ability to eat 2 to 3 hours before or 1 hour or under. This time frame is important specifically because of how your body digests different types of food. For example the higher the fat content is in the food you eat the longer it will take your stomach to empty, making you feel full longer and slowing down the availability of the food you eat for fuel. Also if you have any food in your stomach there will be a percentage of your blood that will be going to your stomach and the rest of your digestive tract to move the nutrients from your food to every part of your body. A problem arises when you are still digesting your food and you start exercising (especially high intensity activities). When this happens your digestive tract and your muscle tissue start to fight for blood and your muscles always win. If your muscles demand too much of your blood then there is not enough for your body to continue digesting your food and your body sends out a fight or flight response that can cause nausea or even vomiting in severe cases. I am sure everyone knows of someone who workout out so hard that they got sick. These things and many more factors change what you can and can't eat before exercise.
Pre Workout Snacks 2 to 3 Hours before your Routine:
If you have plenty of time before you plan to start your routine then you can eat pretty much any food you want, just steer away from foods that are really high in fat. Ideally you want to have a 60-20-20 combination meaning your meal/snack consists of 60 percent carbohydrate and 20 percent of both fat and protein or slightly more carbohydrate. This will allow you to digest your food in time for your workout as well as give you the needed carbohydrate to get through your workout feeling as energized as possible and with the best available nutrient level assuming that you ate a well balanced nutrient dense meal and not a bag of fast food. So basically if you have 2 to 3 hours until your exercise routine then eating a full meal or snack consisting of regular foods will be just fine.
1 Hour or less:
If you don't have a long time to allow your food to digest properly then you need to apply some restrictions. If you have around an hour before you exercise, you need to focus only on easily digestible high carbohydrate snacks like fruit, bread, pasta, rice, sweet potato etc. I know that many of you are probably surprised at some of the items included here but if you need something that needs to be digested quickly these are some of the best options. Also you need to keep the portion size very small so your body can digest the food you take in as quickly as possible. If you are under 45 - 30 minutes there will be no solid food that your body can digest quickly enough to be usable for activity. In this case you have to use very simple carbohydrates like fruit juice, honey, etc. to get the carbohydrate into your system as quickly as possible with as little digestion time as possible. Now in both of theses cases, as I said before you need to increase the carbohydrate levels as this is the main fuel source needed for immediate physical activity. A ratio of 70-15-15 of carbohydrate, fat and protein respectively is about the lowest content of carbohydrate you want. Just be sure to take in a large amount of water as well to properly dilute the carbohydrate you eat so you don't tax your digestion any more than you have to.
Now, there is really no major benefit to eating a snack 3 hours before or 30 minutes before as what is more important is going to be what works best for your personal schedule. Don't worry about trying to change your eating habits for one or the other just be aware that what you should eat is different with differing time constraints. Also you don't even necessarily have to eat just before exercising, the only effect is that you may not feel as energetic and therefore may not get as productive or intense of a workout as you might want. That may slow down your progress but not by much especially if it only happens occasionally.
After your workout session is done, it is very important to get in a good meal as soon as you can to properly refuel your body, replacing both your lost carbohydrate stores and making sure you have the proper protein, and nutrient stores to speed your recovery/healing as much as possible. With this meal you should again be around a 60-20-20 ratio or if you feel particularly tired then again increase the amount of carbohydrate by 5 to 10 percent. Again this should be a full blown meal and not just a snack but if a full meal is not possible right after your workout then a snack with the same ratios followed by a meal as soon as you can get one is the best option.
Now I know we have not given any specific ideas of meals or snacks and that is because everyone eats differently, has access to different foods, has personal or medical restrictions to specific types of foods etc. Do your best to create your own combinations and as long as you hit our target ratios that we outlined above then you have a good snack/meal. As always try and make the best choices with as much fresh and unprocessed foods as much as you can.
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