What Type of Protein Is Best Before Bed?

You've probably heard that a scoop of casein protein (the slower-digesting cousin of the ubiquitous whey protein) before bed is best for overnight muscle growth. But does that come at a cost of sleep quality?

A new study (https://pubmed.ncbi.nlm.nih.gov/42413910/) put this to the test in resistance-trained adults. After a resistance training session, participants drank either whey protein, casein protein, or a carbohydrate control, all 30 minutes before bed, on separate occasions.

Compared to the control drink, whey protein significantly improved how fast you actually fall asleep, how much of your time in bed you spend actually asleep, total sleep time, and how good people rated their own sleep the next morning. All of those hit statistical significance.

Despite being the one with the "slow release, feeds you overnight" reputation, casein performed no differently than the carb-only control on any sleep measure.

Why? The researchers theorize that because whey digests faster and spikes amino acids (the building blocks of protein) in your blood sooner than casein does, that faster delivery may be doing more for sleep than the slow trickle casein is known for.

Casein still has a real role for overnight muscle protein synthesis, but if better sleep after a hard night's lifting session is the goal, whey protein in the 30 minutes before bed has real evidence behind it now.

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You can find out more here. As usual, nothing in this post is to be read as medical advice. Always consult your doctor before trying any new supplement or training program. Stay safe and stay fit!**