What to eat around a workout
The question
What should you eat before and after training, how far ahead or behind the session, and how much does the timing really matter?
What the evidence says
Start by throwing out the stopwatch. The meal before training and the meal after it are not two events with two deadlines; a proper meal eaten two hours before a session is still being digested during and after it, so it covers both sides at once. Together they form one feeding window several hours wide. Total daily protein does most of the work, and timing around the workout is fine-tuning on top of that.
Before a session, the standard advice holds up. The major sports nutrition position stand recommends a mixed meal with both protein and carbohydrate one to four hours out, with 0.25 to 0.40 g of protein per kg of body weight, which is 20 to 32g for an 80kg person. That one-to-four-hour range is not flat. It flexes with meal size: a large meal wants the three-to-four-hour end so it can clear your stomach, while a small snack can sit an hour or less before the start.
The size rule is about comfort, and the discomfort is common. A review of gut complaints in sport put symptoms at 30 to 50% of endurance athletes. During hard exercise blood is pulled away from the gut toward working muscle, digestion slows, and whatever is still in your stomach gets jostled, which is why running provokes far more trouble than cycling or swimming. The main dietary culprits are large meals, and meals heavy in fat or fiber, eaten too close to the start. None of this applies after the session: once the work is done, a big meal carries no comfort penalty.
The famous 30-minute post-workout “anabolic window” does not survive contact with the trials. Muscle stays sensitized to protein for at least 24 hours after training. The cleanest direct test, a 10-week trial in trained men, gave 25g of protein either immediately before or immediately after every session and found no difference in strength, muscle growth, or body composition. Two recent analyses back this up: one restricted to trials that directly randomized pre versus post protein found no meaningful effect on lean mass, and a network analysis covering 116 trials and 4,711 people ranked post-exercise protein best for muscle mass while finding the differences between placements small next to the daily total. If you ate a solid meal before training, the post-workout meal can wait until you are hungry.
On dose, 20 to 40g of protein per meal is the efficient target, but the old claim that anything above 25g is wasted has been overturned. A 2023 tracer study fed lifters 100g of whey after a session and followed it for over 12 hours: the large dose produced a greater and much longer muscle-building response than 25g, with almost none of the extra burned off. Large doses are used, just more slowly. Carbohydrate has a different job entirely. In a direct test, adding 50g of carbs to an adequate protein dose did not raise muscle protein synthesis at all; carbs refill glycogen, and refilling it fast only matters if you train again within about eight hours. Train once a day and glycogen refills fully over 24 hours regardless. After endurance sessions the balance shifts toward carbs plus protein, since adding protein to carbohydrate after long cycling raised muscle repair, whereas after lifting the meal should lead with protein.
Training on an empty stomach does not appear to cost you muscle. A meta-analysis of four trials found no significant difference in muscle or strength gains between fasted and fed lifting when daily protein was adequate, though the trials were small and mostly at high risk of bias. What fasted training does change is what happens afterward: the feeding window is anchored to your last meal, not to the workout clock, so with nothing eaten beforehand, prompt protein after the session matters more. One more quirk is worth knowing: exercise briefly blunts appetite, for roughly 30 to 60 minutes, so not being hungry right after training is normal and waiting costs nothing. And if you train in the evening, the case for a protein snack before bed gets stronger.
Key studies
| Study | Year | Design | n | Finding |
|---|---|---|---|---|
| Kerksick et al. (ISSN position stand) | 2017 | Position stand / review | — | Protein plus carbohydrate 1 to 4h pre-training at 0.25 to 0.40 g/kg; muscle stays sensitized to protein for at least 24h post-exercise; rapid post-exercise carbohydrate (0.6 to 1.0 g/kg) matters most when fast glycogen restoration is the goal. DOI: 10.1186/s12970-017-0189-4 |
| Aragon & Schoenfeld | 2013 | Narrative review | — | The pre versus post distinction matters less than protein-adequate meals near training; a substantial meal 2h before digests through the session, making the window several hours wide. DOI: 10.1186/1550-2783-10-5 |
| Schoenfeld et al. | 2017 | RCT (10 weeks) | 21 | 25g protein immediately before versus immediately after each session: no difference in strength, hypertrophy, or body composition. DOI: 10.7717/peerj.2825 |
| Casuso & Goossens | 2025 | Meta-analysis (5 RCTs) | — | Trials directly randomizing pre versus post-training protein show no meaningful timing effect on lean mass (SMD −0.08). DOI: 10.3390/nu17132070 |
| Zhou et al. | 2024 | Network meta-analysis (116 trials) | 4,711 | Post-exercise protein ranked most effective for muscle mass; night-time protein best for strength. DOI: 10.1123/ijsnem.2023-0118 |
| Trommelen et al. | 2023 | RCT, isotope tracer | 36 | 100g whey after resistance exercise gave a greater, more than 12h anabolic response than 25g, with negligible extra oxidation; no evidence of an absolute per-meal cap. DOI: 10.1016/j.xcrm.2023.101324 |
| Staples et al. | 2011 | Acute crossover | 9 | Adding 50g carbohydrate to 25g whey after leg resistance exercise did not raise myofibrillar muscle protein synthesis beyond protein alone. DOI: 10.1249/mss.0b013e31820751cb |
| Breen et al. | 2011 | Acute tracer | 10 | After endurance cycling, protein added to carbohydrate raised myofibrillar (not mitochondrial) muscle protein synthesis. DOI: 10.1113/jphysiol.2011.211888 |
| Vieira et al. | 2025 | Meta-analysis (4 RCTs) | — | No significant difference in hypertrophy or strength between fasted and fed resistance training; fasted training trended toward greater fat loss. Small samples, mostly high risk of bias. DOI: 10.1016/j.jbmt.2025.08.003 |
| de Oliveira, Burini & Jeukendrup | 2014 | Review | — | 30 to 50% of endurance athletes report GI symptoms; large, fatty, or high-fiber meals close to exercise are a primary nutritional cause, via delayed gastric emptying, gut hypoperfusion, and mechanical jostling (worst in running). DOI: 10.1007/s40279-014-0153-2 |
| Schubert et al. | 2014 | Meta-analysis | — | Acute exercise transiently suppresses appetite hormones (lower acylated ghrelin, higher PYY and GLP-1), blunting hunger for roughly 30 to 60 min afterward. DOI: 10.1007/s40279-013-0120-3 |
| Snijders et al. | 2015 | RCT (12 weeks) | 44 | ~28g protein before sleep during a resistance program produced greater muscle mass and strength gains than placebo. DOI: 10.3945/jn.114.208371 |
Confidence rating and why
Moderate. The central conclusion, that the feeding window is hours wide and daily protein dominates, rests on a direct 10-week randomized trial, two independent meta-analyses from 2024 and 2025, and a position stand that all point the same way. The per-meal dose range is near consensus, and the 2023 tracer work correcting the per-meal cap is unusually rigorous. What caps the rating: the exact meal-size and lead-time cutoffs before training come from clinical consensus rather than trials, gut tolerance varies widely between people and is trainable, and the extra urgency of post-workout protein after fasted training is a reasoned inference from the timing literature, not a directly tested claim.
What to do with this
Eat a normal mixed meal, protein and carbs together, one to four hours before training. Scale the lead time to the size: a full meal three to four hours out, a small snack an hour or less. Aim for 20 to 40g of protein in it.
After training, get another 20 to 40g of protein within a few hours. There is no need to sprint to a shaker. If you are not hungry straight after the session, wait; appetite comes back within the hour.
If you trained on an empty stomach, move the post-workout meal up. With no earlier meal covering you, eating protein promptly after the session is the one case where speed plausibly matters.
Keep pre-workout meals smaller and earlier the harder and more jarring the session. Runners need the most caution here, cyclists and swimmers less. Skip heavy, fatty, or high-fiber food close to the start.
Carbs after a workout are only urgent if you train again within about eight hours. Otherwise fold them into your normal day. After long endurance sessions, pair them with protein.
If you lift in the evening, a protein snack before bed is worth considering on top of all this.
What we do NOT claim
- That there is a narrow post-workout window you must hit. The direct trials and meta-analyses put it at several hours, dominated by daily intake.
- That protein above roughly 0.4 g/kg in one meal is wasted. Larger doses are used, just more slowly; the per-meal range is about efficiency, not a hard cap.
- That post-workout carbohydrate timing matters for someone training once a day. It matters when a second session comes within about eight hours.
- That adding carbs to an adequate protein dose builds more muscle. Carbs restore glycogen; they do not add to muscle protein synthesis.
- That fasted training impairs muscle growth when daily protein is adequate. The pooled trials say it does not, though they are few and small.
- That a large pre-workout meal directly hurts performance for typical trainees. The evidenced effect is gut discomfort, and tolerance is individual and trainable.
- That post-workout meal size needs limiting or timing for comfort. Portion size after training is a daily-total question, nothing more.