Pre-Training Snack Ideas: 20g and 30g Carb Options for Young Athletes
The question I get asked more than almost any other isn’t “what should they eat” — it’s “what am I actually meant to put in the kit bag.” Between school finishing and a 5pm session, or a match that’s an hour later than expected, there’s rarely time for a proper meal, and “just have something” doesn’t help much when you’re standing in a kitchen with ten minutes on the clock.
This is the practical answer to that: a working list of pre-training snacks, split by roughly how much carbohydrate they provide, so there’s something concrete to reach for rather than a decision to make from scratch every time. It’s the companion piece to the full day of eating post — that one covers the whole day, this one is just about the window right before training.
Why this snack, and why carbohydrate specifically
Carbohydrate is the body’s preferred fuel for training, and how much of it someone needs day to day scales with how much they’re actually doing — roughly 3-5g per kg of body weight per day for light, low-intensity activity, up to 8-12g/kg/day for athletes training at a very high volume (more than three hours a day). I won’t pretend those numbers are something to calculate at home from a blog post — where an individual athlete sits on that range is exactly the kind of thing worth working out properly with some support, not self-diagnosing from a table. But it’s useful context for why “eat more carbs before training” isn’t a throwaway line — it’s proportionate to what’s actually being asked of the body.
The pre-training snack itself is solving a narrower problem: topping up before a session, particularly when there’s been a gap since the last proper meal. It’s separate from fuelling during a session — shorter sessions (under an hour) generally don’t need carbohydrate during at all, sessions of one to two hours benefit from around 30g an hour, and anything over two and a half hours can use up to 90g an hour. That’s a different conversation for a different post. This one is about what goes in before the whistle or the warm-up starts.
20g or 30g — which one fits
There isn’t a strict rule here, and it doesn’t need to be weighed out to the gram. As a rough guide: a 20g snack suits a shorter runway — an hour or so before a lighter session, or a genuinely tight window between school and training. A 30g option makes more sense when there’s a bit more time to digest (60-90 minutes), or the session or day ahead is heavier than usual — a match, a double session, an exam-piece rehearsal. If in doubt, it’s better to have something than to skip it while trying to work out which category it falls into.
20g snacks — home-made
- A banana
- 2 dates
- Honey on toast
- A crumpet
- A porridge pot
- A bagel thin
- 40g of flapjack
20g snacks — from the shop
- A Grenade bar
- A Trek bar
- 3 Belvita biscuits
- A Deliciously Ella oat bar
- 250ml chocolate milk
- 2 fig rolls
- A Nakd bar
- 40g of milk chocolate
- 30g of dried fruit
30g snacks — for a bigger gap or a heavier day
- A scone
- A slice of banana bread
- A Clif bar
- 500ml sports Lucozade
- 4 jelly babies with a porridge pot
- A bagel thin
- 35g of raisins
- A crumpet
Getting the timing right in practice
The closer the snack is to training, the more it’s worth favouring something plain and easily digested over anything heavy, high in fibre or very high in fat — that’s more likely to sit uncomfortably once movement starts. This is also not a place to experiment for the first time on a match day. If a snack is new, try it before a normal training session first, so there’s no surprise about how it sits.
The other thing that makes this actually happen on a school day is deciding it in advance rather than at the moment it’s needed. A ten-minute Sunday reset — a few bagel thins in the freezer, a box of oat bars in the kit bag, dried fruit portioned into small bags — means the choice on a Tuesday is “which one” rather than “is there anything at all.”
If the gap feels bigger than a snack can fix
Occasionally what looks like a snack-timing question is actually a bigger one — energy that’s flat well before the session ends, or a sense that intake generally isn’t keeping pace with how much training is happening across the week. A pre-training snack won’t fix that on its own, and it’s worth a proper look rather than something to keep patching with an extra bar here and there.
Get in touch to find out more about sports nutrition support for young athletes, or to talk about what this could look like for your school or club.
