Protein Before vs After Workout: What Actually Matters

For 20 years lifters were told to slam protein within 30 minutes of finishing or "lose the workout." The research has moved on. The window is wider, more forgiving, and the rules are simpler than the supplement industry made them.

The Original "Anabolic Window" Claim

Late-90s research suggested a sharp 30-minute window after training where MPS was maximally responsive. Subsequent better-designed trials showed the window is more like 4–6 hours — narrower if you trained fasted, wider if you ate beforehand.

The Pre-Workout Meal Covers a Lot

A 30–40 g protein meal 1–2 hours before training keeps plasma amino acids elevated through most of the session and well into the recovery window. For most lifters who eat before training, the "post-workout urgency" question largely disappears.

When Post-Workout Matters Most

• Fasted training: No pre-meal means higher breakdown. Take 20–30 g protein within 30 minutes post.
• Two-a-days: Faster recovery between sessions matters. Post-workout protein is non-negotiable.
• Late evening training: Roll the post-workout dose into your pre-bed casein feeding.

The Per-Meal Dose

0.4 g/kg of high-quality protein per feeding maximally stimulates MPS in young adults. Older lifters need ~0.6 g/kg per meal to hit the same threshold. Going higher doesn't extend the response — it just fuels energy metabolism.

The Real Hierarchy

1. Hit your total daily protein (1.6–2.2 g/kg).
2. Distribute across 4 evenly spaced meals.
3. Have protein within 1–2 hours either side of training.
4. Cap the night with 30–40 g of slow protein before bed.

The Bottom Line

Stop sprinting to the shaker. Eat protein around your workout — pre or post, ideally both — and hit your daily total in 4 balanced feedings. The 30-minute panic window is a marketing relic.