I Finally Learned What to Eat and Drink Before My Workouts—and The Difference Was Immediately Positive

I'm guilty of training on an empty stomach. I'm a get-up-and-go kind of girl when it comes to heading out for a run. It's not that I think I shouldn't eat before I train - quite the opposite, in fact. Everything I know about fuelling points to how important it is - but the truth is, I don't always prioritise it the way I should.

Don't get me wrong, if I'm heading out on a longer run, I will make sure I've eaten beforehand to give me energy. My downfall is what happens after. I don't always consciously focus on refuelling or getting enough carbs in for the rest of the day, despite what I'm asking from my body training-wise. And with a half-marathon around the corner, I knew I needed to take fuelling more seriously, not just before workouts, but afterwards too.

Over the past year, the conversation around under-fuelling and RED-S (Relative Energy Deficiency in Sport) has become increasingly hard to ignore. Once a term confined to elite athletes, RED-S is now widely recognised in recreational exercisers too, particularly women.

The 2023 IOC consensus statement, published in the British Journal of Sports Medicine, made it clear that low energy availability can affect anyone training regularly, not just those with obvious signs of restriction.

What struck me most when reading it was just how easy it is to under-fuel without even realising it. It's not necessarily about eating very little or following a restrictive diet. It's the gap between what you're asking your body to do and what you're giving it to do it with.

And, for a lot of active women, the gap has been quietly normalised by years of 'clean eating' messaging, and the idea that exercising more and eating less is somehow the healthier choice.

So I decided to test things properly. For two weeks, I'd commit to fuelling properly - before and after every session - and pay attention to what actually changed. What I really wanted to know was whether it had any impact on my performance, recovery and energy levels.

Keep scrolling to find out how I got on. And if you're keen to read more on fuelling your workouts, find out what happened when I tried Mel Robbins' eating first-thing in the morning recommendation, plus our guides to what to eat before a workout, what to eat after a workout and the best foods to eat before the gym.

I Tried Fuelling Properly Around My Workouts For Two Weeks – And It Changed How I Felt

What is under-fuelling workouts – and why does it matter for women?

It turns out under-fuelling is a lot more common than I first thought.

"Under-fuelling happens when the body isn't getting enough energy to support both exercise and basic physiological functions like hormone production, bone health, brain function and metabolism," explains Bethany Francois, a specialist eating disorder dietitian.

What surprised me most was that it doesn't necessarily mean someone is skipping meals or intentionally restricting food. "Even if someone is eating regularly, they may not be consuming enough relative to their training load and intensity," she says.

In other words, you can be eating what feels like a healthy, balanced diet and still not properly fuel your workouts - particularly if you're training consistently when juggling a busy lifestyle.

That's something Francois says she sees often among active women. "A common misconception is that fuelling only affects elite athletes or those who appear very lean. In reality, many active women can fall into low energy availability when juggling busy lives, exercise routines and unhelpful messaging around clean eating and weight control."

That really resonated with me - and it made me wonder what else I'd been missing.

How important is fuelling before and after exercise?

The short answer? Very. For a more in-depth answer, I turned to Holly Mason, a Les Mills trainer and marathon runner, to see if under-fuelling is something she sees regularly in her clients.

"All the time," she says. "Carbohydrates aren’t a choice when running; they are 100% a necessity." The misconception that eating carbs will somehow undo the work of training is still surprisingly common, and still doing damage, she adds.

Her pre-workout guidance is reassuringly simple. For runs under 90 minutes, you don't need to fuel during the session, as long as you've eaten properly beforehand. A carbohydrate-rich breakfast is enough to top up glycogen stores for an hour-long run.

"My go-to breakfast is a toasted bagel topped with a banana and honey, which totals around 80-90 grams of carbohydrates," says Holly.

But fuelling doesn't stop the moment you finish. What you eat matters just as much, and it's the part most people often neglect, says Mason. "Once you’ve finished your run, aim for a re-fuel meal focused on both carbohydrates and protein to aid with recovery and muscle repair," she advises.

The evidence backs her up: a 2021 systematic study found that refuelling with carbohydrate after exercise significantly speeds up how quickly your muscles restock their energy stores, compared to not refuelling at all. In other words, skipping recovery fuel doesn't just leave you tired; it slows down how well your body bounces back for the next session.

This was the lightbulb moment for me. I'd always given some thought to what I ate before a run, and barely any to what came after.

Francois' bottom line sums it up. "Don't exercise fasted, no matter how early in the morning it is, and view carbs as your best friend."

My review of fuelling my workouts

Week 1

The first few days of the experiment took some adjusting. Even though I was aware of the science behind pre-workout fuelling, I worried I'd feel sluggish, so I kept things simple: porridge before an early run and toast with peanut butter before strength sessions.

Almost straight away - which I wasn't expecting - my energy levels felt steadier. Normally, my runs tend to peak early before becoming a bit of a slog halfway through. But in the first week, I felt more consistent during my sessions. I didn't notice any dramatic changes in my performance, but I also didn't get that sluggish feeling I'd anticipated.

Where I probably did slip up was the recovery side. I made a conscious effort for the first couple of sessions, but as the week went on, I stopped properly prioritising it. Which, in hindsight, felt slightly ridiculous because on the days I did make more effort to have extra carbs and protein, I noticed I felt far less drained later in the day.

Week 2

By week two, eating before I worked out started to feel much less like an effort. I'd settled into a routine that felt realistic rather than overly structured.

I also became more aware of how differently I felt on the days when I properly refuelled afterwards, compared to when I didn't. After a longer run, I'm usually guilty of forgetting I need to eat more than I would on a normal day, but once I started making the effort to stock up on carbohydrates and protein, my energy levels held up noticeably better throughout the day.

It was a mindset shift more than anything. As soon as I became conscious of it, the habit of neglecting recovery started to change on its own.

Physically, I started to see the benefits too. My legs felt less heavy throughout the day, I wasn't getting the mid-afternoon energy crash, and I generally felt like I was coping better with the demands of training.

That isn't to say fuelling transformed my running overnight. I wasn't suddenly faster or hitting personal bests. But I felt more consistent, physically and mentally.

More than anything, the experiment made me realise how easy under-fuelling becomes normalised, especially when you're busy and trying to fit exercise around everyday life. I'd spent years focusing on whether I needed food before a run, without paying nearly as much attention to whether I was properly recovering afterwards.

And, honestly? That's the habit that's stuck with me most.

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