What to Eat Before a Workout

Christine Rosenbloom, PhD, RDN, FAND
The ideas and suggestions written below are provided for general educational purposes only and should not be construed as medical advice or care. Always seek the advice of a physician or other qualified health provider before beginning any physical fitness or health- and nutrition-related activity.
What to Eat Before a Workout?
Jamie, a competitive swimmer for his university, dips into the pool at 6am for practice, then it’s back home before his first lecture at 8:30am.
Madeline, a 42-year-old software developer, is training in the evening for her first marathon to support her favourite charity.
Thomas, a 34-year-old vegetarian and aspiring actor, goes to the gym each afternoon for strength training.
Although their goals are different, they all have the same question: what should I eat before exercising? Jamie, Madeline, and Thomas have different pre-exercise fueling needs, depending on what they’ve eaten throughout the day and what they plan to eat once they’ve finished exercising. While their question is what to eat before exercise, they should also be asking about what, and how much, to drink—which is just as important.
Why should you eat before a workout?
Eating before activity can delay fatigue and help you exercise at your best. A tired athlete won’t perform well and may lose power, strength, and speed during a workout. Additionally, eating before exercise can help with focus and mental alertness. Exercise may feel harder and less enjoyable for a less-focused, tired athlete.
Why should you hydrate before you exercise?
Drinking plenty of fluids before (and during) exercise helps prevent fatigue and dehydration, especially when exercising in hot and humid conditions. Many exercisers begin their workout slightly dehydrated, so to help optimise your performance, it’s important to have some water before hitting the gym.

What should I eat and drink before I exercise?
What to eat and how much to drink before exercise depends on several factors—one strategy does not fit all! First, it depends on what you’ve had to eat and drink earlier in the day. For example, Thomas, the afternoon strength-training exerciser, may not need a pre-workout snack if he ate lunch before his workout. If breakfast was his only meal that day, he should plan to have a snack an hour or two before going to the gym.
What to eat and drink also depends on the intensity, duration, and type of exercise. A moderately intense run lasting two hours requires a different fueling strategy than a high-intensity, short-duration sprint.
When planning a pre-workout snack, first consider the timing. In general, as you get closer to exercise time, the snack or meal should get smaller and higher in carbohydrates. If there are three or more hours before a workout, a carbohydrate-rich meal with some protein and fat can be eaten with plenty of time for the food to be digested and absorbed before exercise. Protein and fat take longer to digest, so as time to exercise gets closer, there should be a greater focus on consuming carbohydrate-rich foods.
Let’s revisit Jamie, Madeline, and Thomas and see what they need to eat and drink to fuel their individual performance:
Jamie’s 6am swim practice leaves little time for a real meal. While on the go, he should focus on quick carbohydrates for activity and to fuel the body. Thirty grams of easily digested carbohydrates can be consumed 15 minutes before exercise, and sports foods like energy chews or gels are favourites for athletes in a hurry. Three CLIF® BLOKS™ Energy Chews provide around 25 grams of simple carbohydrates. Jamie could pair the BLOKS with a sports drink to add fluids and more carbohydrates to his pre-workout routine. After practice, he should eat a balanced and nutritious breakfast with carbohydrates, fat, and ideally 20 grams of protein to help him recover from his morning practice. Wholegrain cereal with nuts, milk, and fruit or a peanut butter and jam sandwich with milk and some fruit would be great options for Jamie.
Madeline trains in the evening, after work and before dinner. She’ll want to concentrate on eating a nutrient-rich lunch, like a bowl of noodles with tofu, and eating a mid-afternoon snack about 1–2 hours before her run. With a mix of carbohydrate, protein and fat, CLIF BAR® Energy Bars can help Madeline achieve her goals.
- Thomas should focus on eating lunch before his strength-training workout, but he may not need a hefty pre-workout snack. While many strength trainers think they need protein pre-workout, protein is best consumed within 30 minutes after a workout to provide needed nutrients to repair and build muscle. To help with recovery, Thomas’ post-exercise nutrition routine should focus on both carbohydrates and protein. CLIF® BUILDERS® vides carbohydrates and 20 grams of complete protein.
All three athletes need to be hydrated during their workouts. In general, 500–600ml of water should be consumed 2–3 hours before exercise and another 200–300ml about 20 minutes before exercise. Although water is always a good choice, sports drinks can be a great option when exercising for over an hour. They provide carbohydrates and the electrolyte sodium to help replenish what’s lost in sweat (carbohydrate electrolyte solutions enhance the absorption of water during physical exercise).
Keep in mind that while dehydration can hurt performance, overhydration can too. So it’s always best to consult a sports nutritionist to develop an eating and drinking schedule that works for you.

3 common mistakes to avoid when fueling before workout:
Not eating enough food
Eating before exercise helps provide the fuel needed to power through a tough workout. Consider the entire day’s meals and snacks and plan them around your exercise to get the most out of a workout.
Not eating the right food
Choose wholesome foods. Quality carbohydrates (like oats, wholegrain breads, cereals, pasta, and rice), fruits, vegetables, and dairy or non-dairy milks are all great choices. Protein from poultry, eggs, fish, seafood, and plant-based sources (e.g., soya, beans, peas, and nuts) provide needed amino acids, and “good” fat from olive oil, avocado, nuts, and seeds deliver beneficial mono- and polyunsaturated fats.
Performance nutrition (like foods from Clif Bar & Company) can provide a practical form of performance nutrition support that is convenient, portable, and tasty.
Too much food
Some people feel that exercising gives them license to eat whatever and whenever they like. Exercise has many positive health benefits and providing the body with the right fuel at the right time can enhance those benefits. But it’s important to be aware of the timing, duration, and intensity of your exercise so that you are not overeating, as that can negatively affect your health.

Check out answers to some common questions on how to fuel for a successful workout:
Is a peanut butter and jam sandwich a good pre-workout snack?
A peanut butter and jam sandwich is a portable, easy-to-make snack that provides carbohydrates, plant-based protein, and good fat. Because this snack has a balanced mix of nutrients, including a good amount of fat, it’s best to eat it a few hours before a workout to allow enough time for your body to digest and absorb this fuel.
What is better for a pre-workout snack?
It depends on how much time there is before a workout, the intensity of that workout, and what an athlete likes to eat. A CLIF BAR® Energy Bar, with carbohydrates combined with some plant-based protein and fat, is best consumed 1–2 hours before a workout and is a convenient on-the-go source of fuel. CLIF® BLOKS™ Energy Chews or CLIF® SHOT® Energy Gels are also great options during activities. Please check package for usage instructions.
Side Bar: 5 pre-workout snacks for activity (consume 1–2 hours before activity)
1 cup of porridge with plant-based milk and dried fruit
A slice of wholegrain bread with almond butter and a small apple
Half a chicken sandwich and a small glass of 100% fruit juice
A CLIF BAR® Energy Bar with a glass of water
A smoothie with fruit, juice or milk, and yoghurt
Side Bar: 4 post-workout snacks with protein to help support recovery
A glass of water and a CLIF® BUILDERS®
A glass of soya milk or low-fat chocolate milk
Trail mix with dried fruit, wholegrain cereal, and nuts
Some cottage cheese and fruit
References:
Burke L, Desbrow B, Spriet L. Caffeine for Sports Performance. 2013. Human Kinetics: Champaign, IL.
Coleman E. Carbohydrate and exercise. In Karpinski C and Rosenbloom C, eds. Sports Nutrition: A Handbook for Professionals, 6th ed. Chicago, IL: Academy of Nutrition and Dietetics; 2017:21-38.
Murray B & Rosenbloom C. Fundamentals of glycogen metabolism for coaches and athletes. Nutrition Reviews. 2018; 76(4):243-259.
Murray B & Osterberg K. Fluid, electrolytes, and exercise. In Karpinski C and Rosenbloom C, eds. Sports Nutrition: A Handbook for Professionals, 6th ed. Chicago, IL: Academy of Nutrition and Dietetics; 2017:107-132.
Rosenbloom C. Sports Nutrition Myths That Deserve to Die but Live On. Nutrition Today. 2017;52(2):57-61.
Thomas DT, Erdman KA, Burke LM. Position of the Academy of Nutrition and Dietetics, Dietitians of Canada, and the American College of Sports Medicine. J Am Diet Assoc. 2016;116:501-528.