I only included them if they controlled for sweating and dietary adaptation periods.

• Tarnopolsky et al. (1992) observed no differences in whole body protein synthesis or indexes of lean body mass in strength athletes consuming either 0.64g/lb or 1.10g/lb over a 2 week period. Protein oxidation did increase in the high protein group, indicating a nutrient overload.
• Walberg et al. (1988) found that 0.73g/lb was sufficient to maintain positive nitrogen balance in cutting weightlifters over a 7 day time period.
• Tarnopolsky et al. (1988) found that only 0.37g/lb was required to maintain positive nitrogen balance in elite bodybuilders (over 5 years of experience, possible previous use of androgens) over a 10 day period. 0.45g/lb was sufficient to maintain lean body mass in bodybuilders over a 2 week period. The authors suggested that 0.55g/lb was sufficient for bodybuilders.
• Lemon et al. (1992) found no differences in muscle mass or strength gains in novice bodybuilders consuming either 0.61g/lb or 1.19g/lb over a 4 week period. Based on nitrogen balance data, the authors recommended 0.75g/lb.
• Hoffman et al. (2006) found no differences in body composition, strength or resting hormonal concentrations in strength athletes consuming either 0.77g/lb or >0.91g/lb over a 3 month period.

Based on the sound research, many review papers have concluded 0.82g/lb is the upper limit at which protein intake benefits body composition (Phillips & Van Loon, 2011). This recommendation often includes a double 95% confidence level, meaning they took the highest mean intake at which benefits were still observed and then added two standard deviations to that level to make absolutely sure all possible benefits from additional protein intake are utilized. As such, this is already overdoing it and consuming 1g/lb ‘to be safe’ doesn’t make any sense. 0.82g/lb is already very safe.

The picture below summarizes the literature. As you can see, 1.8g/kg (0.82g/lb) is the point at which additional protein intake ceases to yield any benefits.

A final objection that is often heard is that these values may be true during bulking or maintenance periods, but cutting requires more protein to maintain muscle mass. Walberg et al. (1988) studied cutting weightlifters and they still found 0.73g/lb was sufficient to maintain lean body mass.

There is normally no advantage to consuming more than 0.82g/lb (1.8g/kg) of protein per day to preserve or build muscle. This already includes a very safe mark-up. There hasn’t been any recorded advantage of consuming more than 0.64g/lb. The only exceptions to this rule could be individuals with extraordinarily high anabolic hormone levels.