Does it matter when you drink your protein shake?
Daytime and nighttime casein supplements similarly increase muscle size and strength in response to resistance training earlier in the day: a preliminary investigation
Not medical advice. For informational purposes only. Always consult a healthcare professional. Terms
Surprising Findings
Nighttime protein did not lead to greater muscle growth than daytime protein.
Popular fitness culture heavily promotes 'casein before bed' as a key muscle-building hack, based on earlier studies showing overnight amino acid delivery boosts muscle protein synthesis.
Practical Takeaways
Focus on hitting 1.8g of protein per kg of body weight each day — you don’t need to time your protein shake around sleep.
Not medical advice. For informational purposes only. Always consult a healthcare professional. Terms
Surprising Findings
Nighttime protein did not lead to greater muscle growth than daytime protein.
Popular fitness culture heavily promotes 'casein before bed' as a key muscle-building hack, based on earlier studies showing overnight amino acid delivery boosts muscle protein synthesis.
Practical Takeaways
Focus on hitting 1.8g of protein per kg of body weight each day — you don’t need to time your protein shake around sleep.
Publication
Journal
Journal of the International Society of Sports Nutrition
Year
2018
Authors
J. Joy, R. Vogel, K. Shane Broughton, U. Kudla, Nathaniel Y. Kerr, J. M. Davison, R. Wildman, N. DiMarco
Related Content
Claims (5)
If you're getting the same amount of protein every day, it doesn't matter whether you drink a shake before bed or at another time — you'll gain the same amount of muscle and strength.
If young guys who lift weights drink a protein shake with 35 grams of casein every day — and keep training — they could gain about 2 to 2.8 kilos of muscle in 10 weeks.
If young, active guys lift weights 4 days a week and eat the same total amount of protein, it doesn’t matter whether they have their casein protein late at night or earlier in the day — they’ll gain similar muscle and strength over 10 weeks.
If young guys lift weights in a structured way for 10 weeks, eat about 1.8 grams of protein per kilo of body weight every day, and have supervision, they can get way stronger—adding around 80–85 kg to their leg press and 11–12 kg to their bench press max lifts.
For young guys lifting weights, eating 1.8 grams of protein per kilo of body weight each day is enough to gain muscle and get stronger in 10 weeks — it doesn’t matter if they take a 35g casein protein shake during the day or before bed.