[svnt]

Their methodology does seem to potentially capture what is at question here, by use of perceived exertion to adjust weight for repetition maximums.

It is possible it doesn’t capture everything, because they don’t say anything here about setting the initial load, or adjusting the load up for low perceived exertion, only down for high perceived exertion.

[daveguy]

It seems like the protocol would detect either benefit, if present.

It makes sense that the body's adenosine re-phosphorylation is not rate limited by creatine at all (which the body produces naturally). In that case, having extra creatine lying around would just make your pee more expensive and give you a nice placebo effect from believing you can lift more. (And placebo effects are real effects, particularly for effort related tasks. Just not due to chemistry of the treatment.)

[seadan83]

Not sure anything is captured. Need control for diet and measurements of existing creatine levels. It takes a few weeks to get creatine higher after supplementation. This is a small sample sized study that strikes me as dubious. Particularly compared to others that have done muscle biopsies. The pre-warm up routine is itself sus, that impacts lifting potentially more than creatine. Creatine also has a role in recovery, good luck measuring that..

[TomHenderson3]

In the introduction they talk about creatine loading. Also, their study is looking at lean body mass changes after the "wash-in" period, so any effect that increased recovery is supposed to have on lean body mass when following the exercise protocol they give for the time period they studied should be captured, no?

[seadan83]

> In the introduction they talk about creatine loading

(1) Yes, that the loading phase was BYPASSED. = (

"Those on creatine did bypass a loading phase, which includes taking 20 to 25 grams daily for up to one week. While it is common to start with a loading phase, it can cause gastrointestinal issues and is not necessary to reach saturation levels – the maximum that the body can store at any one time. "

My understanding, to reach saturation without a loading phase - it takes about 3 to 4 weeks. (Could be wrong, going off of memory there.)

With loading, I've read it takes 1 to 2 weeks to reach saturation.

(2) Without measuring creatine levels, what was even tested? How many people were creatine "non-responders?" How many people were getting plenty of creatine from their diets already?

(3) Was the creatine regimen effective and optimal? Water intake is another factor. I don't think a set of 50 people divided between 2 groups is going to be anywhere near enough to capture a nuance like efficacy of the regimen vs no regimen.

> Also, their study is looking at lean body mass changes after the "wash-in" period, so any effect that increased recovery is supposed to have on lean body mass when following the exercise protocol they give for the time period they studied should be captured, no?

I'd say no, simply because it is not known whether the wash-in period was actually a wash-in period without knowing if creatine levels actually changed in a significant way. Second, the study group of beginner weight lift lifters is a chaotic data set. The gains of lifting weights vs not lifting weights is likely magnitudes different from creatine vs no-creatine supplementation. Some beginners might easily get 10% more muscle mass vs 5% for others. An effect that is expected be very low is going to be completely lost in the noisy data. Let alone that we are starting from a questionable baseline.

Overall, since the body can absorb up to about 5g of creatine a day, and the body is likely already intaking 1 or 2g per day - this study is kinda only looking at the effect of an increase of creatine from a moderate dosage to a maximal dosage, across beginner weight lifters. It's like, say you're a bit dehydrated, instead of drinking 500ml of water per day, you now start drinking 550ml of water and then measure any changes from starting a brand new weight lifting routine.