This question might not suit the site, if so I apologise.
I'd like to regularly test my maths skills, essentially finding out if I'm getting better or worse at a maths in general and then plot the data. The rational behind this is I'd like to find out if things like regular exercise, changes to diet, etc. make a measurable different to me.
My concern is although there are ways of testing my analytical and mathematics abilities using some form of test, whatever test I use I will inevitably get better at taking the test outside of any changes I make to my diet etc.
The only method I can think of to work around this is to make no changes for some length of time, and test myself during this period, thereby being able to identify the degree to which I get better just by taking the tests multiple times - but this is flawed because it's unlikely to be a linear process.
I understand the standard for this is to have multiple test subjects and a control group, but can someone do this type of work alone?