Fuelling vs Fasting – When training fasted is appropriate and when you want to fuel up.

Fasted or fuelled. It seems to be a never-ending debate amongst athletes and fitness enthusiasts.

Should you eat before a workout or train on empty?

The simple answer is – it depends.

It depends on your goals; what you’re training for, the goals of that session, how it fits into your weekly schedule, and a host of individual factors. There is however, a lot of misconception around the benefits of training fasted, especially when it comes to body comp or weight loss. Here’s a few things to consider:

Going low and slow?
If you’re heading out to spin the legs or cruise through some kms with no fixed agenda, then you can probably skip breakfast and get going.

Why? Your muscles store enough glycogen to keep you going for at least an hour at a cruisy pace. Training in a fasted state encourages you to become more efficient at tapping into those all important fat stores – the fuel source that’s vital for long races (NB some medical conditions require eating before exercise so speak to your doctor or nutritionist if unsure). It’s important to note though that burning fat for energy is NOT the same as fat loss. So if you think hammering out sessions on no food is helping you lose weight it isn’t, that entails a much more holistic approach to training and diet plans. So if that’s your primary goal seek out some qualified assistance and get started on the right track.

If you are going longer than an hour or so, you’ll want to start getting some fuel in as you go. Replenishing glycogen will ensure you have enough energy to get through the entire workout as planned, there’s no point cutting a workout short simply because you are under fuelled. Depending on what your workout looks like, this might mean an appropriate break mid session or packing some portable options. During session options include Rice cakes with PB&J, sports drinks, banana or an energy bar. Incorporate some electrolyte rich drinks or salty foods to help maintain hydration.

Going short, sharp, fast?
Take the time to fuel up.

Why? Having even a small carb rich breakfast will top up glycogen stores and enable you to hit your intensity as planned. That means you’ll be able to hit those reps and interval times, and maximise training adaptations that enable you to get fitter and faster. Going into these types of sessions under-fuelled only serves to make you slow – your body isn’t efficient at utilising fast burning carbs, and even if you feel good, you aren’t training at your max intensity.

This doesn’t mean you necessarily need to be up hours beforehand to eat, even a banana or a PB&J bagel will fuel you through a short intense workout. If it’s a longer session, consider topping up during with a sports drink or energy bar.

The other benefit that comes from eating pre-session is that it gives you some practice for race or competition day. No matter what event you compete in, nutrition and fuelling is a vital part. Your gut, just like your muscles, needs training and to be able to tolerate fuel on race day you have to get used to being able to stomach fluids and energy while at high intensities.

Post workout recovery nutrition is also important. Sometimes though, especially after a harder session, hunger can be dampened which is when liquid meals can be beneficial as they are easier to get down. A smoothie with protein, carbs, fats and antioxidants will help replenish glycogen and assist in muscle recovery.

– Pip Taylor