The random timer is especially useful for martial arts and other sports that require explosivity or quick reflexes.
Here are some example exercises for various sports:
Example exercise for cardio:
Perform jumping jacks for 3 minutes. When you hear "Down", go down and do a pushup, when you hear "Up", jump up and raise both your knees.
Example exercise for boxing:
Perform a boxing run (cardio exercise) on a heavy bag. When you hear "1,2", quickly give a jab and a cross. When you hear "3,4", give 2 powerful hooks. Set the timer to end after 3 minutes.
Example exercise for karate:
Do a reverse punch when you hear "Quick", a mawashi geri when you hear "Strong", and a counterattack when you hear "Defend". Set the timer to 2-5 seconds, and stop after 30 repititions.
Example exercise for football:
Sprint on an agility ladder, then break left or right when you hear "Left" or "Right". Repeat 10 times.
Example exercise for brazilian jiu jitsu:
Perform stationary Ebi (hip escapes), then practice a sweep if you hear "1", or a triangle if you hear "2". Repeat 100 times.
Example exercise for MMA:
Shadow box, then sprawl if you hear "Down", and perform a powerful combination of attacks if you hear "Attack". Repeat for 5 minutes (a full round).
Example exercise for basketball:
Dribble around freely, then pass if you hear "Pass", shoot if you hear "Shoot", or accelerate with a crossover if you hear "Go". Keep going for 3 minutes.