Recovery: Post-Workout Nutrition Timing
Aragon & Schoenfeld 2013 (PMID 23360586) found the anabolic window extends to 2 hours post-exercise. Protein at 0.4g/kg and carbs at 0.8g/kg within that window optimize glycogen resynthesis and MPS simultaneously.
| Measure | Value | Unit | Notes |
|---|---|---|---|
| Protein Dose — Post-Workout Target | 0.4 | g/kg body weight | Aragon & Schoenfeld 2013; maximizes MPS without diminishing returns from excess dose |
| Carbohydrate Dose — Post-Workout Target | 0.8 | g/kg body weight | Ivy 1998; sufficient to initiate rapid glycogen resynthesis phase (7-8 mmol/kg/hr) |
| Anabolic Window Duration | 2 | hours post-exercise | Window extends to 2 hours for most resistance training; narrower (~30 min) for glycogen-depleting endurance exercise |
| Glycogen Resynthesis Rate — Immediate Post-Exercise | 7–8 | mmol glycogen/kg wet wt/hr | Rapid phase during first 30-60 minutes; drops to 4-5 mmol/kg/hr after 2 hours |
| MPS Elevation — Post-Workout | 3–5 | hours elevated above baseline | Resistance exercise elevates MPS for 3-5 hours post-workout regardless of immediate nutrition |
| Effect of Immediate vs Delayed Protein (1hr) | 25 | % greater leg lean mass gain | Levenhagen et al. 2001: immediate post-exercise protein produced 25% more lean mass than 3-hour delay |
Post-workout nutrition timing is one of the most discussed and most misunderstood topics in sports nutrition. The anabolic window is real — but it is 2 hours wide, not 30 minutes, and its importance depends heavily on what you ate before training.
| Nutrient | Optimal Dose | Optimal Timing | Effect Size | Practical Food Example |
|---|---|---|---|---|
| Protein (high-quality) | 0.4 g/kg body weight | Within 2 hours post-exercise | Moderate — +25% lean mass vs 3hr delay | 30g whey shake; 150g Greek yogurt; 4 eggs |
| Carbohydrate (moderate-GI) | 0.8 g/kg body weight | Within 0–30 min for endurance; 2 hr for strength | High for glycogen — 7-8 mmol/kg/hr resynthesis | Banana + rice; white bread + jam; sports drink |
| Leucine (via protein source) | 2.5–3 g | Same as protein window | High — rate-limiting for MPS activation | Whey (dominant source); chicken breast; cottage cheese |
| Creatine (supplemental) | 3–5 g | Post-workout preferred over pre | Small-moderate — ~1% strength improvement | Creatine monohydrate powder; mixed with water or shake |
| Water / Electrolytes | 125–150% of sweat loss | Immediate — begin during cooldown | High for hydration status | Water + sodium; electrolyte drinks; whole food meals |
The 2-hour window framework comes from Aragon & Schoenfeld’s landmark 2013 review (PMID 23360586), which synthesized prior nutrient timing research and established that the practical boundaries of the post-exercise anabolic window are substantially wider than the 30-minute window that had dominated gym culture. The mechanism behind any window at all is the heightened sensitivity of muscle tissue to amino acids and insulin in the post-exercise period — a sensitivity that is elevated for 2+ hours but greatest in the first 30-60 minutes.
For glycogen, the timing mathematics are more urgent. Ivy (1998 — PMID 9694422) showed glycogen resynthesis proceeds at 7-8 mmol/kg wet weight per hour during the first 30-60 minutes post-exercise — approximately twice the rate of late-window synthesis. Athletes with sessions less than 24 hours apart have a genuine urgency to consume carbohydrates immediately post-workout.
Levenhagen et al. (2001 — PMID 11157940) demonstrated the timing benefit directly: subjects consuming protein and carbohydrate immediately post-exercise gained 25% more leg lean mass than those delaying intake by 3 hours. The dose was 10g protein + 8g carbohydrate — much smaller than current 0.4g/kg recommendations — suggesting the effect at optimal doses is likely larger.
The practical priority hierarchy: total daily protein first, post-workout window second, and specific timing within the window third.
Related Pages
Sources
- Aragon & Schoenfeld 2013 — Nutrient Timing Revisited
- Ivy 1998 — Glycogen Resynthesis After Exercise
- Levenhagen et al. 2001 — Post-Exercise Nutrient Intake Timing
Frequently Asked Questions
How important is the post-workout window if I eat enough protein throughout the day?
For athletes with regular meal patterns who eat adequate total protein (1.6-2.2g/kg/day) throughout the day, the window's importance decreases substantially. Aragon & Schoenfeld's review found that total daily protein intake is the dominant variable; timing provides an additive but secondary benefit. The window matters most when training fasted or when more than 4-5 hours pass between the pre-workout meal and post-workout eating.
Does the post-workout window apply to cardio as well as strength training?
For glycogen-depleting endurance exercise, the window is narrower and more critical — approximately 30-45 minutes for maximum glycogen resynthesis rate. For resistance training sessions without significant glycogen depletion, the 2-hour window is more forgiving.
Is liquid nutrition better than whole food post-workout?
Liquid nutrition (shakes, milk) reaches peak plasma amino acids faster — approximately 60-90 minutes versus 90-120 minutes for whole food. This matters more when training sessions are closely spaced (twice-daily) or when the glycogen window is critical. For single-session athletes, whole food within the 2-hour window is equally effective.
What is the minimum protein dose that triggers MPS post-workout?
Approximately 20-25g of high-quality protein (containing 2.5-3g leucine) is the minimum threshold to maximally stimulate MPS in young adults. This corresponds roughly to 0.25-0.3g/kg body weight. The 0.4g/kg target provides a buffer above this threshold.
Does adding carbs to post-workout protein increase MPS?
Not directly. Carbohydrates post-workout work primarily through insulin to suppress muscle protein breakdown rather than directly stimulating MPS. The combination optimizes net protein balance (MPS minus MPB) and addresses glycogen restoration simultaneously, making it superior for recovery when sessions are less than 24 hours apart.