Fuel 101: Timing

Fuel 101: Timing

The Macro That Most Apps Ignore.

Most nutrition apps track what you eat. Very few help you think about when you eat it. For someone trying to manage body weight with minimal exercise, timing is largely irrelevant. For an endurance athlete training regularly, it's one of the highest-leverage adjustments you can make.

The principle is straightforward: your body's ability to use different nutrients changes throughout the day depending on what your muscles have just done and what you're about to ask them to do. Eat the right things at the right times and the same total intake becomes meaningfully more effective.

Before training: setting yourself up

What you eat before a session determines how much fuel you arrive with and whether your gut is going to cause problems mid-effort.

2 to 3 hours before is the ideal window for a proper pre-session meal. At this point you have time to digest a moderate serving of carbohydrates with some protein, fat and fibre without it sitting in your gut during the session. A bowl of porridge with fruit and a handful of nuts, or rice and chicken, or eggs on toast. The specifics matter less than the combination: carbohydrate for glycogen top-up, a moderate amount of protein, and not so much fat or fibre that digestion is still very much in progress when you start.

30 to 60 minutes before is the window where simplicity helps. If you're eating this close to the session, go for easily digestible carbohydrates with minimal fat, fibre or protein. A banana, a slice of white toast with honey, a small portion of rice cakes. The goal is a bit of blood sugar elevation before you start, not a full meal that competes with your muscles for blood flow.

First thing in the morning is where a lot of athletes get this wrong. Training fasted has a place for some easy aerobic sessions. But heading out for a hard interval session, a long group ride or a race simulation without eating first means working against an already depleted glycogen store. Some people feel fine fasted. Most perform noticeably better with something in them.

During training: fuelling on the move

For sessions under about 60 minutes, and assuming you arrived properly fuelled, additional carbohydrates during training aren't necessary. Your glycogen stores can sustain an hour of moderate to hard effort without replenishment.

Beyond 60 minutes, taking carbohydrates in during the session becomes progressively more important as session length increases.

A practical framework:

• 60 to 90 minutes: 30 to 45 grams of carbohydrate per hour

• 90 minutes to 3 hours: 45 to 60 grams per hour

• Over 3 hours: up to 90 grams per hour, using a mix of glucose and fructose sources

The source is less important than the consistency. Sports drinks, gels, chews, bananas, rice cakes, dates — all work. What doesn't work is waiting until you feel empty, which by that point means you've already compromised the session. Small, regular intake from around 45 to 60 minutes in is more effective than sporadic larger amounts.

Fluid should accompany carbohydrate intake, both to aid absorption and to manage hydration. Concentrated carbohydrate with insufficient fluid slows gastric emptying and can cause GI distress.

After training: the recovery window

For a long time, sports nutrition research focused heavily on the "anabolic window," the idea that nutrients consumed in the 30 to 45 minutes immediately after training had dramatically elevated effects compared to later intake. More recent evidence suggests the window is somewhat longer than this and that total daily intake matters more than perfect timing.

That said, there are still good reasons to eat or drink within an hour of finishing a hard session.

Your muscles are most receptive to glycogen replenishment immediately after training. If you have another session within 24 hours, prioritising carbohydrates post-session accelerates this replenishment significantly. If the gap between sessions is longer, timing matters less, but eating promptly still supports the process.

Protein consumed shortly after training provides the amino acids needed to begin muscle repair. Aim for 25 to 40 grams. A recovery meal with a good protein source alongside carbohydrates covers both bases without needing supplements.

One point that often gets overlooked: the practical case for recovery nutrition is often logistical. Athletes who don't eat promptly after training often find they're not hungry for a couple of hours, then ravenously hungry late at night, and end up with a dietary pattern that shifts too much intake to the end of the day and not enough to the period where it can actually support recovery.

Evening meals and the next day's training

How you fuel the evening before a hard session matters almost as much as the morning of. Glycogen replenishment is a gradual process. A carbohydrate-rich evening meal the night before a long ride or a hard track session is not over-eating. It's pre-loading your fuel stores for work that begins hours later.

Conversely, an easy recovery day is an opportunity to slightly reduce carbohydrate intake and emphasise protein and vegetables, giving your digestive system a lighter load and your glycogen stores a chance to be topped up from a lower baseline rather than running full all the time.

Why this matters more than marginal gains

Timing adjustments are often dismissed as marginal gains: small percentages that only matter at the elite level. But the practical impact on amateur athletes is frequently more significant than the research suggests, because the baseline to improve from is often very poor.

An athlete who's been training fasted, not eating during long rides and delaying recovery nutrition for hours after hard sessions can make substantial improvements simply by addressing those habits. The fundamentals of timing aren't marginal. They're foundational.

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This is the final article in the Fuel 101 series. Start from the beginning with Calories.