Simon Sinek argues that fitness results come from 20 minutes of daily effort, not occasional intense workouts. One session won't change your body, but showing up regularly does, even when you slip up and eat cake or miss a day.
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If you go to the gym and you work out and you come back and you look in the mirror, you will see nothing. And if you go to the gym the next day and you come back and you look in the mirror, you will see nothing. So clearly there's no results, can't be measured, it must not be effective. So we quit. Or if you fundamentally believe that this is the right course of action and you stick with it, you commit yourself to an act of service, you commit yourself to the regime, the exercise, you can screw it up, you can eat chocolate cake one day, you can skip a day or two, but if you stick with it consistently, you'll start getting into shape. Going to the gym for nine hours does not get you into shape. Working out every day for 20 minutes gets you into shape. It's not about the events, it's not about intensity, it's about consistency.