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Protein (Whey & Casein) — Frequently Asked Questions

This content is for informational purposes only and does not constitute medical advice. Consult your healthcare provider before starting any supplement. Full disclaimer

Frequently Asked Questions

Does the "anabolic window" after training really matter?

The "anabolic window" is real but much wider than the often-cited 30 minutes. Research shows muscle protein synthesis is elevated for 24-48 hours after resistance training. A 2013 meta-analysis by Schoenfeld et al. found protein timing had no significant independent effect when total daily protein was controlled. Practical advice: consume protein within a few hours of training, but do not stress about exact timing.

Whey concentrate vs isolate — which is better?

For most people, whey concentrate (WPC 80) is the best value — it is cheaper, tastes better, and the performance difference vs isolate is negligible. Choose isolate if you are lactose-intolerant (isolate has <1% lactose), need very low-fat/carb protein, or are competing in a weight-class sport where every calorie matters. The protein quality is identical.

How much protein per meal for maximum muscle building?

Research suggests ~20-25 g of high-quality protein (providing ~2.5 g leucine) maximally stimulates MPS in young adults. Older adults need more — approximately 40 g per meal to overcome anabolic resistance. Going above these thresholds per meal does not waste protein (it is still used for energy and other functions) but does not further increase MPS. Spread protein across 3-5 meals for best results.

Full Protein (Whey & Casein) Guide

References

  1. (). A systematic review, meta-analysis and meta-regression of the effect of protein supplementation on resistance training-induced gains in muscle mass and strength. British Journal of Sports Medicine. DOI
  2. (). Ingestion of whey hydrolysate, casein, or soy protein isolate: effects on mixed muscle protein synthesis at rest and following resistance exercise. Journal of Applied Physiology. DOI
  3. (). Protein ingestion before sleep improves postexercise overnight recovery. Medicine & Science in Sports & Exercise. DOI