An extrinsic reward is a reward that is external and tangible. It is a reward that is visible to others like food.

Extrinsic rewards include monetary compensation, promotion, and tangible benefits.

receiving a free t-shirt for exercise performance. can this be an extrinsic reward/

The pursuit of an activity for external reward is called extrinsic motivation in psychology. It involves engaging in an activity to earn a reward or avoid punishment, rather than for the inherent satisfaction of the activity itself.

Extrinsic motivation refers to something external that encourages someone to do something. This could include the promise or possibility of a reward.