It's not like this was a scientific measurement. It was part of Mike's training. The timings were for his benefit, to gauge whether his performance was improving. It's the same as training for any sport or physical activity -- you do it over and over and try to get better. And given how few superstrong people there currently are on Earth in the MCU, it stands to reason that their strength-training equipment for the superstrong would be kind of makeshift. So I don't see the problem.