Push-ups alarm

Prop the phone up so the camera can see you.

Do your reps. Only full ones are counted.

Reach your number and the alarm stops.

A few seconds of effort raises your heart rate, and your brain follows.

Start with a number you can do half-asleep and raise it as the streak grows.

Cannot do it one morning? Switch to a backup dare: Math, Type a Phrase or Shake. You still owe a dare, just a different one. Walk away half-way and the alarm rings again in 15 to 20 seconds.