Everyone knows that diet and exercise lead to improved health. But when should we do each, and in what order?
The Mayo Clinic tells us, “Knowing when and how much to eat and drink before you exercise can make a big difference in how you feel during and after your workout.”
According to mothers everywhere, we shouldn’t swim right after we eat. And, while it’s true that digestion does divert circulation away from muscles, is it really significant enough to avoid getting in the water, or on the treadmill?
To answer these questions I did some research, and I found that most sources agree: while it’s best not to eat sugary and fatty foods right before a vigorous workout, the appropriate healthy snack an hour or so before, or even during your workout is safe, and can be beneficial.
Having a simple carbohydrate snack before, or during your workout can be beneficial because it provides your body with an additional source of energy, which helps to accomplish two things:
- It ensures that you have enough energy to complete your vigorous workout.
- It prevents your body from using protein as a source of energy to fuel your workout.
Here’s how it works: To fuel your workout, your body first uses up all of the carbohydrates you have stored in your body (called glycogen) and all of the carbohydrates you have recently added (via snacking or meals). After your body has used up all of its carbohydrates, it then starts breaking down protein into glucose to be used as energy. You don’t want to use protein as fuel for your workouts because doing so limits your ability to build and maintain important tissues like muscles, bones, skin, hair, etc.
So, snacking on a simple carbohydrate food before and/or during your workout can ensure that you have enough energy to finish your workout, and that your body does not use up its valuable protein to fuel your workout.
About.com has published an excellent article that provides more on this topic. Check it out here:How Carbohydrate Provides Energy For Exercise
WHEN and HOW MUCH should we eat?
Yes, food is tasty. And for some of us it can be comforting, have family or cultural significance, and have strong associations with social activities. But, on the most basic level, food is fuel. You need it to live, to breathe, to move, and certainly, to exercise.
To illustrate food’s function as fuel, if you were to skip lunch and then try to go for a run after work, your low blood sugar would lead to flagging energy and low motivation. So, skipping meals is not the way to go because you are expecting your body to operate at higher levels with not enough fuel.
That said, it is also not advisable to eat a heavy meal before your workout. In this situation, your body won’t know whether to expend its energy digesting or exercising.
This is from the University of Iowa Hospitals & Clinics:
"If vigorous exercise is attempted within a few minutes after a large meal…this can cause nausea, cramps in the side, and general discomfort."
So where does this leave us? When should we eat with regard to exercise?
The Mayo Clinic suggests eating larger meals 3 or 4 hours before exercise and smaller meals 2 or 3 hours before. And, they go on to say that most people can snack right before or even during exercise. You just have to experiment and see how you feel.
Timing is important because the body digests fat, protein, and carbohydrates at different rates. Therefore, fat, which takes the longest to digest, generally 4 – 6 hours, should be consumed the furthest away from your scheduled workout, whereas carbohydrates, which can be digested in 2 hours or less, may be consumed closer to when you hit the gym. (Source: BNET Research Center)
WHAT should we eat?
We now know that the most efficient fuel for workouts is carbohydrates. Carbohydrates are easier to digest than fats and proteins, and won’t stay in your digestive system as long – allowing your body access to more energy in a shorter amount of time.
Before and during exercise, you’re looking to eat a snack that is low in fat and fiber (too much fiber can stimulate digestion and elimination at an inconvenient time), and high in simple carbohydrates. This is because you want your snack to digest very rapidly and you want it to supply a large amount of energy – and that is exactly what simple carbohydrates do.
Here are some suggestions:
- Fresh Fruit
- Fruit Smoothie
- Energy Bar
- Sports Drink
Don’t Forget About Water
Water is essential to the body for transportation of nutrients, waste removal, and circulation. It is very important to stay hydrated on a daily basis and especially when you’re working out. As your body begins to exert itself, your temperature begins to rise. Perspiration is your body’s way of cooling itself off, but unless the water evaporated is replaced, blood circulation will also decrease, putting unnecessary stress on your cardiovascular system. (Source: Peak Performance)
These are general guidelines. Always listen to your body and do what works for you. And, of course, consult your doctor for more specific information.