It is important to remember that a study finding almost always is an AVERAGE result of a group. This means that a certain individual on a workout or diet might have effects ABOVE or BELOW average.
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People will use this as an excuse to why they don't trust science, claiming that they are special. But it is really naive to assume that YOU are different from the average. The best approach is to first assume that you will respond as the average Joe and THEN make individual adjustments.
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Even these adjustments should be systematically tried and evaluated. For example, if most people get strongest by training a muscle 2 times a week, but you aren't making progress, try switching to 4 times a week for 12 weeks and evaluating how your strength progressed compared to 12 weeks training twice per week.

This is obviously not optimal because other factors like training experience may influence your results, but its the best way to approach the situation when research is lacking. It's basically applying the scientific method on an individual level.
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