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.
See the scientific wording
In young males participating in resistance training, consuming a total daily protein intake of 1.8 g/kg body weight is sufficient to achieve significant increases in muscle size and strength over a 10-week period, with no additional benefit observed from ingesting a 35g casein supplement either during the day or at night.
Very strong evidence
Randomized trialsOne moderate-quality study supports this claim, so treat this as an early signal rather than settled science.
What the research says
1 study reviewedSupporting (1)
Randomized Controlled TrialHuman2018
The study found that young men gained muscle and strength just as well with 1.8g of protein per kg of body weight per day, whether they took a casein shake during the day or at night.
Contradicting (0)
No contradicting studies found yet
That doesn't mean it's settled — it just means no study has tested the opposite.
Quality-weighted scoring: we follow the GRADE framework — each study is rated High, Moderate, Low, or Very Low based on study design, methodology rigor, and risk of bias. A single high-quality RCT can outweigh several weaker observational studies.
Scores reflect study quality, not just count.
Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting study
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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.
Evidence from Studies
Supporting (1)
Community contributions welcome
Daytime and nighttime casein supplements similarly increase muscle size and strength in response to resistance training earlier in the day: a preliminary investigation
The study found that young men gained muscle and strength just as well with 1.8g of protein per kg of body weight per day, whether they took a casein shake during the day or at night.
Contradicting (0)
Community contributions welcome
Score Breakdown
No multi-axis breakdown available yet. The overall Pro / Against score above is the best signal.
- No clinical evidence is available; the score reflects mechanistic plausibility only.
What Would Prove This
Per GRADE and EBM methodology, here is what ideal scientific evidence would look like to definitively prove or disprove this claim, ordered from strongest to weakest.
Systematic Review of Casein Timing on Muscle Hypertrophy and Strength in Resistance-Trained Young Males Consuming 1.8 g/kg/day Protein
Systematic review and meta-analysis of randomized controlled trials comparing day vs night ingestion of 35g casein in young males (18–35 years) undergoing structured resistance training for ≥10 weeks, with total protein intake controlled at 1.8 g/kg/day, measuring changes in muscle cross-sectional area and 1RM strength.
Double-Blind RCT of Day vs Night 35g Casein Supplementation on Muscle Adaptation in Young Men on 1.8 g/kg/day Protein During 10 Weeks of Resistance Training
Double-blind, randomized, placebo-controlled trial assigning young males to consume 35g casein during the day, at night, or placebo, while maintaining 1.8 g/kg/day total protein and standardized resistance training for 10 weeks, with primary outcomes: muscle thickness (ultrasound) and strength (1RM).
Prospective Cohort Study of Casein Supplementation Timing and Muscle Gains in Natural Bodybuilders with Controlled Protein Intake
Prospective cohort of young male resistance trainers consuming ~1.8 g/kg/day protein, tracking self-reported casein timing (day vs night) over 10 weeks, with objective measures of muscle size and strength at baseline and follow-up.
Cross-Sectional Analysis of Protein Timing Habits and Muscle Mass in Young Male Lifters Consuming 1.8 g/kg/day Protein
Cross-sectional survey and measurement of young males engaged in resistance training, recording habitual protein intake (verified by recall or diary), casein timing, and muscle mass via DEXA or ultrasound, focusing on those reporting ~1.8 g/kg/day intake.
Case-Control Study Comparing Casein Timing in Young Males With High vs Low Muscle Gain on 1.8 g/kg/day Protein
Matched case-control study where 'cases' are young males with high muscle gain (>10% increase in muscle thickness) and 'controls' with low gain (<5%) over 10 weeks, comparing frequency and timing of 35g casein use, all with verified 1.8 g/kg/day total protein.