A research review offers a useful reality check for your next gym session: drinking protein after lifting did not produce greater lean-mass gains than drinking it beforehand. If you already ate protein before training, an immediate second shake may be less urgent than you think.
The finding comes from a 2025 meta-analysis in Nutrients. Its practical message: plan your protein across the day instead of treating the final rep as the start of a nutritional countdown.
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What the Timing Research Actually Found
Researchers Rafael A. Casuso, PhD, and Lennert Goossens, PhD, analyzed five studies directly comparing protein consumed before versus after resistance training lasting at least four weeks.
“Protein timing does not importantly modify exercise-induced changes in lean body mass,” they concluded.
A leg-press result favored pre-workout protein, but the evidence was limited. The authors cautioned that “more investigation is needed to reach a more robust conclusion.”
That makes pre-workout protein a reasonable option, rather than a proven shortcut to bigger muscles.
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Your Last Meal Changes the Equation
The International Society of Sports Nutrition’s nutrient-timing position stand explains that “the size and timing of a pre-exercise meal may impact the extent to which post-exercise protein feeding is required.”
In practical terms, a protein-containing meal before lifting belongs in your recovery plan. You do not need to pretend it disappears when your workout ends.
The society’s separate protein position stand notes that “benefits are derived from pre- or post-workout ingestion.”
It also recommends spreading servings out: “These protein doses should ideally be evenly distributed, every 3–4 h, across the day.”
It lists roughly 20–40 grams per serving as a general guide, with needs varying by body size, age, and exercise.
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Build a Daily Plan, Not Another Deadline
A 2022 review led by Everson A. Nunes, PhD, examined 74 randomized trials. Its conclusion: “increasing daily protein ingestion results in small additional gains in LBM and lower body muscle strength gains in healthy adults enrolled in resistance exercise training.”
LBM means lean body mass. That review supports adequate daily protein; it does not establish that everyone needs shakes on both sides of a workout.
Men’s Journal takeaway: Check your last protein-containing meal and your daily intake before automatically mixing another shake. Pre-workout protein can count toward recovery; consistency matters more than creating another deadline.
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