What you eat before and/or after exercise can have a big impact on your workout as you are doing it and also the results you experience afterward. There are lots of myths surrounding pre and post-exercise nutrition and a lot of misunderstandings too. The main reason for this is that there are lots of valid approaches and what works for one person may not work for another. Similarly, your training goal will affect what you should and shouldn’t eat before and after exercise.
With those variables in mind, here are some guidelines based on three common training goals. Use the guidelines as a basis from which to design your own pre and post-exercise eating plan and don’t be afraid to experiment to find out what works best for you.
Exercise for fat loss
If you are exercising for fat loss, you may find that you burn fat more efficiently on an empty stomach. If you are in a semi-fasted state, your blood glucose drops and you will preferentially burn fat instead of carbohydrate.
Bodybuilders and boxers have known this for many years which is why so many of them do fasted, early morning, cardio to lose fat.
You don’t have to get up at the crack of dawn to experience fasted exercise; just leave it several hours between your last meal and your workout. Of course, make sure you are well hydrated by drinking plenty of water but just steer clear of food and beverages that contain calories.
Fasted exercise – not for everyone
Some people find that early morning fasted exercise leaves them feeling tired and weak. This can be negated by eating a well-balanced meal the night before and taking branch-chain amino acids prior to exercise.
When exercising for fat loss it is important not to consume calories while you exercise so sports drinks containing sugar or carbs are not recommended. While they may give you energy, you are likely to end up consuming more calories than you use in your workout. Plain water is best.
On completion of your workout, even when training for fat loss, you need to eat to provide your body with fuel for recovery. In the post-exercise period, insulin sensitivity is very high with means food consumed immediately after exercise is partitioned into your muscles and liver and away from your fat stores. A meal containing moderate amounts of healthy carbs, lean protein, plus a small amount of healthy fat is ideal at this time. Increased insulin sensitivity isn’t a license to eat a huge meal – you’ll end up ingesting more energy than you used in your workout, a small meal is best.
Fat loss summary:
- Pre-exercise – fasted exercise may preferentially burn more fat. Consider using BCAA if you find fasted exercise makes you feel tired or weak
- During exercise – water only, no sports drinks containing sugar/carbs
- Post-exercise – a small, balanced meal to promote recovery
Exercise for muscle growth
Building muscle requires an abundance of protein, plenty of carbohydrates for energy, and healthy fats too. Workouts are tough and you’ll need to eat before exercise to provide the energy you need to exercise. The old adage is, if you want to be big, you need to eat big.
Pre-exercise meals for muscle growth start several hours before training. Each meal consumed should be high in protein and carbs. As training approaches, it may be necessary to switch from solid food to easily digestible liquids to avoid digestive discomfort.
Food for thought – during-exercise nutrition
Some experts believe that consuming protein and carbs during training is also useful for a) sustaining energy, b) preventing excessive muscle breakdown and c) kick-starting recovery. At the very least, consuming liquid calories during a workout will contribute to the required calorific surplus necessary for muscle growth. As muscle building requires both protein and carbs, both should be included in your in-workout drink.
After exercise, the sooner you can eat, the better. Muscle building workouts are very catabolic, that is to say they cause a lot of muscle breakdown. To stop catabolism and promote anabolism (the repair and building process) protein and carbohydrates are required.
As liquids are easily digestible, a protein and carb shake is ideal immediately after exercise followed within an hour or so with a solid meal. This meal should contain fast-acting carbs such as white rice, potatoes, or white pasta to maximize recovery and take advantage on increased insulin sensitivity.
Muscle building summary:
- Pre-exercise – solid, balanced meals up to 2-4 hours before exercise, liquid meals closer to exercise
- During exercise – a protein/carb drink (optional)
- Post-exercise – a protein/carb drink immediately after exercise, a solid meal in the next 1-2 hours consisting of fast-acting carbs and protein plus some healthy fat. Meal size should be large to provide sufficient calories and nutrients
If you are exercising to maintain your current weight, be healthier, or just develop a good level of fitness, your workout will probably include both cardio and strength training. To get the most out of your workouts, you want to be sufficiently fueled but not overfed as this may lead to weight gain. Similarly, you do not want to be underfed as this may limit performance.
Pre-exercise meals should be balanced to provide energy but not so heavy that you feel overly full. If you are unable to have a solid meal, a liquid protein/carb drink will suffice.
Sports drinks – useful during long or intense workouts
During general exercise, water is usually sufficient but a sports drink may be useful to ward off fatigue, especially if you want to exercise at a high level of intensity or for a long duration. Isotonic drinks contain around 6 grams of carbs per 100 ml of water and also provide electrolytes which will replace the minerals you lose when sweating. However, be aware that consuming carbs will also interfere with fat burning.
Post exercise meals should also be balanced. As general exercise is not as intense as training for muscle growth, it is not usually necessary to consume a protein/carb shake immediately after exercise. Instead, a meal within 1-2 hours after exercise will be enough to recover from a general workout. However, if you are watching your carb intake most of the time to help with weight control, the post-exercise period is the best time to consume carbs as they will be preferentially partitioned into your muscles and liver and away from fat stores.
General exercise summary:
- Pre-exercise – balanced, healthy meals prior to exercise or consider a carb/protein shake if solid meals are not possible
- During exercise – water should be sufficient but a sports drink may be useful for long or very intense workouts or if a pre-exercise meal was not possible
- Post-exercise – a balanced meal to promote recovery within 1-2 hours. This is a good time to consume carbs if you normally keep your carb intake low for weight control
The key to deciding what to eat before, during, or after exercise is the question “what does my body need”. Carbs are used for energy but, if you want to burn fat faster, you should nix the carbs so there is less of a competition for fuel. Protein is essential for muscle growth and especially important after exercise that causes muscle breakdown e.g. strength training. After exercise, your body needs food to kick-start the repair and recovery process. Small, balanced meals are best for weight loss but to fuel muscle growth, you have to eat big and preferably very soon after exercise.
Once you crack the pre, during, and post-exercise code, you will be well on your way to maximizing the effectiveness of your workouts and ensuring you start recovering as soon as possible after.