A 2.2 g/kg protein target showed no extra muscle benefit over 12 weeks
In short
A 12-week trial assigned 108 women aged 40–77 to protein targets of 0.8, 1.6 or 2.2 g/kg/day; the complete-case analysis of 83 women detected no protein effect on BIA-estimated skeletal muscle mass. Resistance training alone produced a 6.68 kg higher estimated leg-press 1RM than the same lifting plus cycling, a finding that does not set protein needs or predict Big 3 performance in younger lifters.
A bigger protein target did not produce a detectable muscle-mass advantage after 12 weeks. Women assigned 1.6 or 2.2 g/kg/day showed no advantage over the 0.8 g/kg/day target on BIA-estimated skeletal muscle mass. For this population and timeframe, the extra protein target did not register as extra muscle on the body-composition reading.
Who was tested, and what did the targets mean?
The trial assigned 108 women aged 40–77 to supervised resistance training (RT) or identical lifting followed by cycling (CT), alongside one of three protein targets. The 12-week complete-case analysis included 83 women. For the primary muscle-mass outcome, neither protein target nor training condition had a detectable effect, and there was no interaction between them. These were assigned intake targets, not proof that everyone consumed precisely the assigned amount.
What changed when cycling was added?
- At week 12, after adjustment for starting values, CT had 2.04 percentage points lower body fat than RT.
- In the same comparison, RT had a 6.68 kg higher estimated leg-press 1RM than CT.
- CT had a 4.53 mL/kg/min higher cycle-derived estimated VO2max than RT.
Adding cycling carried a leg-press strength tradeoff in this group, alongside better estimated aerobic fitness and lower body-fat percentage. CT also involved more exercise, so the comparison cannot isolate modality from the extra work. The distinction between outcomes also matters when reading about aerobic and resistance training.
What belongs beside your Big 3 log?
Training choice, rather than assigned protein target, separated the strength results in this trial. When reviewing your Big 3 lifts and fairlift strength score, keep a record of added cycling too. A leg-press estimate cannot be converted into kilograms lost from a squat. For nutrition context, distinguish a daily protein target from a whey supplement dose.
A null protein result does not establish equivalence between 0.8, 1.6 and 2.2 g/kg/day. BIA estimates muscle mass rather than measuring it directly. Twelve weeks in women aged 40–77 cannot establish that 0.8 g/kg/day is sufficient for young lifters.
Frequently asked questions
Did 2.2 g/kg/day of protein build more muscle than 0.8 g/kg/day?
The 12-week trial in women aged 40–77 detected no difference in BIA-estimated skeletal muscle mass attributable to the assigned targets of 0.8, 1.6 or 2.2 g/kg/day. Complete-case analysis included 83 of the 108 women assigned.
Does adding cycling reduce strength?
In this trial, identical resistance training plus cycling produced a week-12 estimated leg-press 1RM 6.68 kg below resistance training alone after adjustment for starting values. That does not mean individuals lost strength from baseline, and the cycling group also did more total exercise.
What improved more in the group that added cycling?
In the 12-week trial in women aged 40–77, the cycling-plus-lifting group had 2.04 percentage points lower body fat and 4.53 mL/kg/min higher cycle-derived estimated VO2max than the lifting-only group, after adjustment for starting values.
Can these results be applied to young Big 3 lifters?
A 12-week trial in women aged 40–77 cannot determine the protein needs of young Big 3 lifters. The strength difference was measured with estimated leg-press 1RM, not a squat, bench press and deadlift total.
Source: PubMed