Your time will gradually increase over time due to muscles strengthening, but perhaps you could adjust for that.
I'd expect that after the first dozen times you do that, any further improvements will be due to muscles strengthening to a far greater extent than to more willpower.
I want to test different techniques for decreasing personal procrastination. What would be an easy way to measure procrastination so that I can do the comparison?
I would also like to hear suggestions for measuring the inverse i.e. how can I measure getting-things-done-ness.