Once I hated running. Then I said to myself do it every morning at least 1.5 km for 21 days in a row. I hated everything in the middle of this process. Did it

Once I hated running. Then I said to myself do it every morning at least 1.5 km for 21 days in a row. I hated everything in the middle of this process. Did it on pure willpower. But since then I somehow can’t spend a week without at least 3km run, and I really like it. I could easily imagine myself spending same 21 days reading about motivation, looking for tricks how to fool myself into it etc. without any stable outcome. Sometimes you just need to man up and push yourself.