Recovery Meals After Hard Intervals: What to Eat and When

The context

An indoor session that counts as hard is usually one of two things: a long piece with rate changes, which can run the better part of an hour, or a hard 2k, which is over in six to ten minutes. Either way the question of what to eat afterwards is usually settled in about thirty seconds at the clubhouse.

The interesting part is that the answer genuinely depends on one thing: when your next session is. If you are back on the erg tomorrow morning, the post-session meal is doing real work. If the next session is on Saturday, it is just dinner. Almost every piece of advice on this subject blurs those two cases together, and most of the confident advice about thirty-minute windows belongs to the first case even though it is usually delivered as if it belonged to the second.

The core idea

The carbohydrate part of the window is real, and it has been measured. In the early post-exercise period, muscle glycogen depletion provides a strong drive for its own resynthesis, and providing about one gram of carbohydrate per kilogram of body mass optimises the process. Co-ingesting protein with carbohydrate can assist glycogen storage ([2] Burke 2017). The underlying experiment is older and blunter: when carbohydrate was taken straight away, glycogen storage ran at 7.7 units per gram of wet tissue per hour over the first two hours, and when the same carbohydrate was delayed by two hours it ran at 2.5 ([3] Ivy 1988). Twelve cyclists on a cycle ergometer, and the authors were careful with their claim: the results suggest that delaying the carbohydrate will result in a reduced rate of muscle glycogen storage. The gap is the measurement; the mechanism is not something this study settled.

What that does not give you is a number in minutes. The supported window is the early post-exercise period of zero to four hours, and the supported quantity is about one gram of carbohydrate per kilogram of body mass. A rule that says "within thirty minutes" and a ceiling of five to seven grams per kilogram per hour are not in these sources, and they are the numbers that get repeated most often. What the wider carbohydrate literature does support is that availability is built across the whole cycle - before, during and in the window between sessions ([4] Burke 2011) - and that during-session rates of 30 to 60 grams an hour are for bouts longer than about seventy minutes ([1] Kerksick 2017).

The muscle-building part of the window is much weaker than it sounds. A meta-analysis of protein timing looked at this directly. With all covariates in the model there was no significant difference in strength or hypertrophy between groups that timed protein differently, and total protein intake was the strongest predictor of the effect size. The authors went further, concluding that the results refute the commonly held belief that the timing of protein intake in and around a training session is critical to muscular adaptations ([5] Schoenfeld 2013). A companion review makes the same case in softer language, noting that the importance, and even the existence, of a post-exercise window varies with the factors involved and that recent evidence has challenged the classical view ([6] Aragon 2013).

That is not the same as saying timing does not matter. The physiology of the meal is different from the outcome it is supposed to change. The post-exercise period is when rapid aminoacidemia promotes a marked rise in the rate of muscle protein synthesis, and proteins with a full complement of essential amino acids and high leucine content that are digested quickly are the more efficacious choice ([9] Phillips 2014). In other words, if you are going to eat protein, the meal right after training is a good moment to eat it. What has not been shown is that the same protein eaten two hours later builds less muscle.

Total protein is the lever. The consensus range for athletes is 1.3 to 1.8 grams per kilogram of body weight a day, consumed as three or four meals of similar protein content, with leucine prominent in stimulating muscle protein synthesis ([8] Phillips 2011). And the evidence has a breakpoint in it: in a meta-analysis of protein supplementation during resistance training, supplementing beyond about 1.62 grams per kilogram a day produced no further gains in fat-free mass, while the same meta-analysis found that supplementation itself increased strength and muscle size ([7] Morton 2018). That breakpoint comes from trials that ran six weeks or more, and it is a finding about fat-free mass rather than a limit on what you need. A daily target of 1.6 to 2.2 grams per kilogram is therefore not defensible - the top of that range has no support, and the useful number is nearer 1.6 than 2.2.

Per meal, the numbers are smaller than they are usually quoted. A dose of 20 to 40 grams of high-quality protein, or roughly a quarter to two fifths of a gram per kilogram, every three to four hours is what appears to favour muscle protein synthesis most, and for carbohydrate the position stand pairs about eight tenths of a gram per kilogram per hour with a fifth to two fifths of a gram per kilogram per hour of protein ([1] Kerksick 2017). Those are the figures to work from. A flat 0.4 grams per kilogram per meal sits at the very top of the supported range, and a per-meal leucine figure in grams is not something these abstracts state at all.

On fluid, the rule is to replace what you lost, not to drink a schedule. After exercise the goal is to replace any fluid and electrolyte deficit, and the speed with which rehydration is needed and the magnitude of the deficit determine whether an aggressive replacement programme is merited ([10] American College 2007). For scale, active athletes in hot weather can lose four to ten litres of water and three and a half to seven grams of sodium across a day, and the advice is to drink aggressively when recovery is needed within a day or when the deficit exceeds five per cent of body mass ([11] Shirreffs 2011). Published per-hour ladders of fluid and milligrams of sodium per hour are not in these sources, and neither is a "replace 150 per cent of your sweat loss" figure. Weigh yourself before and after and drink against the number you get.

No food beats another food, because none of them were compared. There is no trial in this set that pits a chocolate milk against a rice-and-chicken plate against a proprietary recovery drink. The evidence is about grams of carbohydrate, grams of protein and litres of fluid. Ordinary food does all three.

And there is a line that is not about food at all. RED-S is defined as impaired physiological functioning caused by relative energy deficiency, with low energy availability as the major cause, and it affects metabolic rate, menstrual function, bone health, immunity, protein synthesis and cardiovascular health ([12] Mountjoy 2018). A recovery plan that assumes you are eating enough is built on that assumption. If it is not true, no timing strategy rescues it.

The how-to

Work out when your next session is before you decide anything. Tomorrow morning changes the plan; Saturday does not. That single question resolves most of the arguments you will have with other rowers about this.

If you are training again within a day, treat the next meal as a refuelling job. About one gram of carbohydrate per kilogram of body mass across the first few hours, with protein at around a quarter to two fifths of a gram per kilogram alongside it. There is no need to drink it in one sitting; the timing that matters is early rather than exact.

If you are not, eat normally. Three or four meals through the day, each with a palm-sized portion of protein, will do more for your next session than a shake taken at the kerb.

Spread protein across the day rather than back-loading it. Three or four doses of roughly a quarter to two fifths of a gram per kilogram, and a daily total between 1.3 and 1.8 grams per kilogram. If you are already eating that much, the post-session shake is close to optional.

Drink against your own numbers. Weigh in before and after a typical session, subtract, and replace. If the difference is more than about five per cent of your body mass, or another session is within a day, be aggressive about it.

Ignore the thirty-minute rule. Nothing in the evidence you are likely to be quoted supports it, and following it strictly usually means a small meal you eat in a hurry.

The trade-offs

The first trade-off is that almost none of this research is about rowers. The glycogen work is twelve male cyclists on a cycle ergometer. The protein work is largely resistance training. The fluid work is about general athletes in hot conditions. You can use these findings, but you are applying them, not reading your own results.

The second is that the glycogen studies start from a depleted state, which is a different situation from finishing a steady forty-five-minute club piece. If your glycogen was never seriously drawn down, the urgency of the early window is proportionally smaller.

The third is that the post-exercise meal is a good time to eat protein because the absorption physiology favours it, not because the muscle-building literature says the clock matters. Those are different claims and it is worth keeping them apart when someone tells you the window is closing. The carbohydrate-with-protein pairing carries a caveat of its own: the position stand itself records that the addition has been questioned, citing Jentjens and colleagues, who failed to show an improvement in muscle glycogen restoration from carbohydrate plus protein compared with carbohydrate alone, and Howarth and colleagues, who came to a similar conclusion ([1] Kerksick 2017).

The fourth is that the line between eating enough and not eating enough is not a timing question at all, and it is the one worth taking seriously.

What to do tomorrow

Pick two.

Weigh yourself before and after your next session and write down the difference in kilos. That is your fluid number, and it takes thirty seconds.

Check your protein against 1.3 to 1.8 grams per kilogram for the day, spread over three or four feedings, and see whether the post-session shake has anything left to do.

If you have a session tomorrow morning, put about one gram of carbohydrate per kilogram into the meals you eat afterwards. If you do not, stop thinking about the window and go to dinner.