Fitness: Is it better to eat before or after exercising?

We’ve all been there: it’s 6pm and you just got home from work. You want to go for a run, but you’re hungry. Should you eat dinner first and risk an upset stomach? Or should you run first, with potentially less energy to power you through?
It’s a question that plagues even the most disciplined exercisers among us. And to make the matter even more complicated, research on the topic is limited, with answers that depend on your unique health and goals.
That said, experts agree that there are some general considerations to keep in mind.
Health experts recommend eating both before and after exercise, for different reasons.
For most people, having a balanced meal rich in carbohydrates and protein two to four hours before a workout will supply enough energy to last the length of your routine. This also allows ample time for digestion and can help reduce gastrointestinal discomfort such as nausea, vomiting or acid reflux, says Dr Martha Gulati, a cardiologist at Cedars-Sinai in Los Angeles who specialises in helping her patients to make lifestyle changes through diet and exercise.
If you have a few hours before you plan to exercise, a pre-workout meal might include a high-quality protein (such as salmon, chicken or tofu), a complex carbohydrate (brown rice, oatmeal or sweet potatoes) and healthy sources of fats (avocado, eggs or nuts), says Dr Cecilia Cordova Vallejos, a sports medicine physiatrist at Johns Hopkins Medicine in the US.
Having a snack about 30 minutes before your workout will also give you an energy boost – especially if you’re doing moderate or high-intensity exercise for longer than 90 minutes, Dr Cordova Vallejos says. She recommend a protein bar or even just an energy gel packet because they are easy on the stomach. Dr Gulati suggests a banana or a piece of your favourite fruit.
Once you’re finished with your workout, aim to consume protein – ideally 20 to 40g within two hours, the International Society of Sports Nutrition recommends – to help support muscle growth and recovery. A can of tuna, a chicken breast or three scrambled eggs with cheese would each fall within that range.
The timing of your meals may also depend on your health or fitness objectives.
If you have a condition such as diabetes where you must manage your blood sugar levels, the recommendations are a little more nuanced, says Jill Kanaley, a professor of nutrition and exercise physiology at the University of Missouri.
Some research suggests that those with type 2 diabetes may be better off having breakfast before they exercise. In one 2017 study of 64 adults with type 2 diabetes in India, for instance, researchers found that those who had breakfast before exercising had much better blood sugar control than those who didn’t eat before their workout.
For people with type 1 diabetes, the suggestions may be different, Prof Kanaley says. Some research suggests, for instance, that fasting before a moderate or high-intensity morning workout can be safe and potentially even preferable for people with type 1 diabetes, depending on your glucose levels upon waking.
Though in general, working out on an empty stomach may come with downsides. In one online survey of about 2,000 endurance athletes published in 2020, participants who said they avoided exercising on an empty stomach said they did so because it didn’t help their training, it hampered their athletic performance and it made them hungrier.
If you’d like to reduce soreness and improve muscle growth and repair after your workouts, eating a little more protein – and spreading it throughout the day – might help you achieve that goal, Dr Cordova Vallejos says.
If you have food allergies or other dietary restrictions or medical conditions, consider consulting a physician, sports medicine doctor or sports nutritionist to figure out a plan that meets your needs.
The most important thing you should do is pay attention to how your body feels when you eat (or don’t eat) before exercise. If you have a protein- or fat-rich snack 30 minutes before a morning workout and it upsets your stomach, Dr Gulati says, try switching to a snack that has a higher carbohydrate concentration. Or if you’re doing a lower intensity workout, like a slow walk or yoga, maybe you don’t need to eat first.
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Over time, you’ll figure out what your body needs, she says. “There isn’t a perfect science,” Dr Gulati says, adding that everyone has different needs, goals, diets and schedules, but if you’re patient, you’ll find a routine that works for you. – This article originally appeared in the New York Times.