I often wonder about studies like this. While this focuses on one area of bodily health, I imagine there are dozens more that can make a difference in one direction or another. If they do a study over two years, how do they account for all the other variables?
Things like eating, drinking, sunshine, stress, taking drugs or vaccines, personal environments, toxic chemical exposure, general lifestyles. Or what exactly is the state of health of the brain at the start of the trials? Thanks for the information.
Randomisation of the study population is the main tool used for minimising the effect of other variables like the ones you mentioned (diet, sunshine exposure etc). If you take a fairly homogenous population, like the older Danish adults recruited into this study, and randomise them into study groups and a control group, you can have a reasonable degree of confidence that any variation in outcome is likely to be attributable to the effects of the intervention. Of course, randomisation can't cancel out the effects of those other variables completely - e.g. perhaps people who are randomised into the heavy resistance training group might be more likely to change their lives in other ways, such as getting outdoors more often or eating different foods. But randomisation is the best tool that exists for this purpose.
Regarding the state of health of participants' brains at the start of the trials, the baseline rs-fMRI was done to ascertain this. Again, not a perfect or completely comprehensive measure of brain health, because researchers are rarely able to obtain the budget required to test absolutely everything they might desire to measure!
I often wonder about studies like this. While this focuses on one area of bodily health, I imagine there are dozens more that can make a difference in one direction or another. If they do a study over two years, how do they account for all the other variables?
Things like eating, drinking, sunshine, stress, taking drugs or vaccines, personal environments, toxic chemical exposure, general lifestyles. Or what exactly is the state of health of the brain at the start of the trials? Thanks for the information.
Randomisation of the study population is the main tool used for minimising the effect of other variables like the ones you mentioned (diet, sunshine exposure etc). If you take a fairly homogenous population, like the older Danish adults recruited into this study, and randomise them into study groups and a control group, you can have a reasonable degree of confidence that any variation in outcome is likely to be attributable to the effects of the intervention. Of course, randomisation can't cancel out the effects of those other variables completely - e.g. perhaps people who are randomised into the heavy resistance training group might be more likely to change their lives in other ways, such as getting outdoors more often or eating different foods. But randomisation is the best tool that exists for this purpose.
Regarding the state of health of participants' brains at the start of the trials, the baseline rs-fMRI was done to ascertain this. Again, not a perfect or completely comprehensive measure of brain health, because researchers are rarely able to obtain the budget required to test absolutely everything they might desire to measure!