What small fitness habit made a bigger difference than you expected?

Progress does not always come from completely changing a training programme or diet. Sometimes a relatively small habit makes workouts more consistent or produces better results over time.

Examples include preparing gym clothes the night before, recording each workout, drinking more water, eating a regular, protein-rich breakfast, or going to bed slightly earlier.

What small fitness habit has made a surprisingly noticeable difference for you?

It could relate to training, nutrition, recovery, motivation, or simply getting yourself to the gym. Was the improvement immediate, or did its value only become apparent after several weeks?

It would also be useful to hear about habits that sounded promising but proved too difficult or inconvenient to maintain.