If you spend any time on fitness Instagram, you’ll have picked up the current line by osmosis: eat more protein, then eat some more, then when you think you’re done, eat a little more still. Especially if you’re a woman over 40. Especially if you’re lifting. Especially if you’re perimenopausal, postmenopausal, or somewhere in the murky middle.
I’ve been quietly nudging my own protein up for a while now. Not because I did the maths, but because everyone else was doing it and I didn’t want to be the woman on the starting line who hadn’t got the memo.
Then this new randomized trial came out, and it made me stop and actually read it properly instead of just reposting the headline. Because the headline is a bit spicier than the reality.
What the trial actually did
The study, published in September 2026 in the Journal of the International Society of Sports Nutrition, enrolled 108 women aged 40 to 77 and had them complete a 12-week program.
Every woman was randomly assigned to two things at once:
- A training style — either resistance training on its own (RT), or the same resistance session followed by cycling (concurrent training, or CT).
- A protein target — either 0.8 g/kg/day (the old-school baseline), 1.6 g/kg/day (the current “athlete standard”), or 2.2 g/kg/day (the “eat more, then more” tier).
Eighty-three women finished and were included in the analysis. The main thing the researchers wanted to know: does more protein actually build more muscle in this age group, and does it matter whether you’re just lifting or lifting and riding?
What they found (and it’s less dramatic than you’d think)
For skeletal muscle mass — the headline outcome — the researchers could not detect a difference between the three protein groups. Not between 0.8 and 1.6. Not between 1.6 and 2.2. Not between 0.8 and 2.2. The higher-protein groups didn’t build measurably more muscle than the lower ones.
Same story for the key secondary outcomes: no detectable protein-dose advantage.
Where the training style did show up:
- Concurrent training (lifting + cycling) came out ahead on estimated aerobic fitness and body-fat percentage.
- Resistance-only training came out ahead on leg-press strength.
Which honestly makes sense: you get better at what you actually do. The cyclists rode. Their aerobic fitness improved. The lifters lifted (only). Their leg press went up more. The plot twist isn’t in the training; it’s in the protein.
“No detectable difference” is not the same as “all doses are equal”
This is the bit that gets butchered in the social media version, so stay with me.
When a study reports no significant difference between two groups, that does not mean the two groups are equivalent. It means the study didn’t find enough evidence in this particular sample over this particular time frame to say one is better than the other. The authors say it themselves in the paper — null protein findings do not establish equivalence among doses.
Reasons this specific trial might have missed a real effect, even if one exists:
- It was 12 weeks. That’s long enough to see some strength gains, but muscle mass changes are slower and messier. A year-long trial might tell a different story.
- Eighty-three women isn’t a large sample when you split them across six subgroups (2 training styles × 3 protein doses). Small differences get lost in the noise.
- Body composition was measured with bioelectrical impedance (BIA) — the same kind of tech in a smart scale. It’s practical, but it’s known to be less accurate than DEXA scanning, especially for small changes.
- Assigned dose is not the same as eaten dose. If a woman was told to eat 2.2 g/kg but actually managed 1.7 g/kg, the gap between the “high” and “middle” groups shrinks on the plate, even if the paperwork says otherwise. The abstract doesn’t tell us how tight adherence was.
- Baseline diet matters. If most women are already eating enough protein, adding more may bump up against the ceiling of what their bodies can actually use.
None of that makes the study bad. It just means “we didn’t find a difference here” is a much more honest statement than “protein above 1.6 is a waste of time.”
The study didn’t find that more protein is pointless. It found that it couldn’t detect an advantage in this group, over this stretch of time, with these tools. There’s a real difference.
So what does this mean for the woman actually training?
Here’s my honest read, as a middle-aged woman who lifts, rides, and would quite like to still be doing both in twenty years.
1. Getting to “enough” is the game. Chasing “more” probably isn’t. If you’re currently eating 60g of protein a day and you’re 70kg, you’re not near enough, and yes — nudging that up will almost certainly help. If you’re already hitting around 1.6 g/kg (about 112g for a 70kg woman), the case for cranking it further starts to look thinner than the internet suggests.
2. Training specificity is doing the heavy lifting. The clearest finding in this trial wasn’t a protein one — it was that cyclists got better at cycling and lifters got better at leg press. If you want a stronger squat, lift. If you want a better FTP, ride. Protein is the raw material. Training is the signal.
3. Build a sustainable routine. This was a 12-week trial of assigned daily protein targets, not a year-long comparison of consistent versus intermittent intake. It cannot establish which of those untested patterns builds more muscle. Sources: Bagheri et al. (2026), PMID 42735207.
4. There’s a mild eyebrow-raise on the safety side. The same research team published a second paper looking at kidney and liver markers in this cohort. Some markers shifted more in the higher-protein groups — not in a “you’re damaging your organs” way, but in a “this is worth watching in longer trials” way. If you’ve got existing kidney concerns, this is a conversation for your doctor, not for Instagram.
A rough working target for real life
Not medical advice, just what the current picture suggests for a healthy active woman:
- Aim somewhere in the 1.4 – 1.8 g/kg/day range if you’re training regularly.
- Spread it across the day — 3 to 4 meals with 25 – 40g protein each lands better than one huge steak at dinner.
- Prioritize real food (eggs, yogurt, chicken, fish, legumes, biltong, cottage cheese) and let shakes fill the gap when real food is a stretch.
- If you’re already hitting this and feeling strong, you probably don’t need to push higher. Put the energy into sleep, consistent training, and enough carbs to actually fuel the sessions you’re paying for in your evenings.
🩷 Building the training half of the equation
Protein only pays off if there’s a training signal for it to answer. If you’re starting from scratch on the strength or cycling side, pop into the shop — there are printable planners, checklists and starter templates to help you build the habit around your real life, not somebody’s Instagram version of it.
The honest take
This one trial doesn’t rewrite everything we thought we knew about protein. It’s a single study, in a specific group of women, over a short window, with an imperfect body-composition tool. The evidence strength is moderate, not gospel.
In the 83 participants included in the complete-case analysis, the trial detected no effect of assigned protein target on BIA-estimated skeletal muscle mass after 12 weeks. That does not establish equivalence between doses or a protein ceiling at the middle target. Sources: Bagheri et al. (2026), PMID 42735207.
Eat enough. Train consistently. Sleep. Repeat. The boring answers are still winning.
Nothing in this article is medical or nutritional advice. If you have kidney, liver, or other health conditions, chat to your GP or a registered dietitian before making big changes to your protein intake — especially at the higher end.
Reference: Bagheri R, Ghobadi H, Mansordehghan M, Camera DM, Kargarfard M. Resistance versus concurrent training with three assigned protein targets in middle-aged and older women: a randomized 2 × 3 factorial trial. Journal of the International Society of Sports Nutrition, 2026. Retrieved from PubMed (DOI: 10.1080/15502783.2026.2720742).
🩷The Endurance Diaries🩷
