It depends on the supplement
For everyday vitamins, whether you take them before or after exercise usually is not important — pairing them with a meal and staying consistent matters more. For supplements aimed at specific fitness goals, timing can be part of the plan, but that is very individual.
Fat-soluble vitamins still do best with food, so a post-workout meal can be a convenient anchor if that is when you eat.
Build the habit around your routine
If you exercise at a regular time, that can become a reliable trigger for your supplement habit. Pillog lets you set a time that fits your routine, check it off from the notification, and see your month as a card, all on your phone with no account.
If your goals are specific — endurance, recovery, and so on — a doctor or pharmacist can advise what actually fits them.