Personal trainer and nutritionist Sarah O’Neill gives her advice on the best foods to fuel your workout and when to eat them
Knowing which foods to eat before you exercise is vital for a winning workout. Hitting the gym on an empty stomach can lead to a listless, lack-lustre effort, while eating the wrong foods pre-exercise can cause unpleasant gastro symptoms such as cramps and nausea.
PT and nutritionist Sarah O’Neill tells us how picking certain foods at the right time will ensure you’re maximising your workout and getting the best results – whether it’s your morning cardio or lunchbreak weight-training session.
Should I eat before my workout?
If you’re exercising at low-ish intensity for up to an hour, you can do so on an empty stomach. One study by the Belgium National Institute of Health found increased fat burn when exercising after an overnight fast, but you’re more likely to tire sooner, meaning you’ll burn fewer calories (and body fat) overall. You’re also more likely to burn protein for fuel when muscle glycogen (the stored carbohydrate that your body uses as fuel during exercise) and blood sugar levels are low, sabotaging that lean tissue growth you’re working so hard for.
If you’ve already eaten two to three hours before your session, there’s no need to overdo the snacks, but it’s all down to the individual and if you’re running out of steam you might want to fuel up to ensure you can go the distance.
What should I eat before my morning workout?
Generally, it’s worth waiting around 30-60 minutes between food and exercise but, if you’re pounding the pavements at the crack of dawn, this can be harder to manage. Keep it light, such as a small handful of nuts or a piece of fruit around 15-30 minutes pre-workout. Bananas are a perfect, easily digested source of carbohydrate, plus they’re rich in potassium, which we lose when we sweat.
Another good choice is a smoothie. As it’s a liquid, the sugars are absorbed more quickly – handy if you struggle to digest whole foods without feeling queasy early in the morning. Blitz up your favourite milk or yogurt, plus half a banana and/or a handful of frozen berries. But beware – packing tons of fruit into a smoothie can deliver sky-high levels of sugar and calories, off-setting your hard work before you’ve even started. Try adding veg such as spinach, beetroot or kale to balance it out.
What should I eat before a lunchtime session?
If you’re working out in your lunch break you’ll have enough time to factor in a snack late morning, ideally 30-60 minutes before training. Respond to how your body is feeling – a snack-sized yogurt (try Greek yogurt, or one without added sugar) or a small handful of dried fruit like apricots may suffice.
If you’re very hungry, opt for a small bowl of low-fibre cereal or porridge, ideally eaten around 60-90 minutes before you exercise. The emphasis is on a carb/protein mix, with the carbs providing your fuel and the protein assisting muscle recovery and growth. If you’re looking for something quick and easy, an oat or fruit-based bar makes a great snack. Just remember to check those labels – don’t eat a 350kcal bar ahead of a 150kcal workout.
What should I eat if I’m exercising after work?
You’ll need to carefully plan your snack for post-work exercise as you’ve already been on the go all day. Avoid fatty foods such as chocolate or pastries (which you’ll spend your whole workout trying to burn off) and instead have a small snack around 60-90 minutes before you exercise of houmous and crudités or pitta, fruit loaf or raisin bread, half a bagel with nut butter, a toasted muffin topped with honey, or something more protein-rich such as leftover cooked turkey or chicken.
Any pre-workout snacks I should be avoiding?
As a rule, avoid anything high in fat or fibre. Fatty foods can take up to four to five hours to fully digest, and fibre is both slow to digest and increases gas production – making you the least popular person at the gym.
Energy drinks before or during your session are not necessary unless you’re exercising at intensity for 90 minutes or more, plus a lot of them have added unnecessary sugar.
How much water should I be drinking before my workout?
For every hour of exercise you’ll need an extra litre of water to replenish what’s lost in sweat. Dehydration can lead to impaired performance and muscle cramps, so get ahead by sipping water in the hour before your workout.
Will a dose of caffeine help?
Seasoned coffee drinkers will be pleased to know caffeine can have performance-enhancing effects, according to the British Coffee Assocation. Caffeine can decrease glycogen use earlier in the session by up to 50%, saving glycogen for later in the session (increasing endurance), and increasing fat burn. However, caffeine is also a diuretic so you’ll need to up your fluids.
Inspired to whizz up a smoothie before your workout? Check out our superfood smoothie boosters to increase the nutritional benefits.