I just run breh.
Not for distance tho i just run hard as shyt for as long as i can a few times on a football field.
Like, i stand on the goalline and just break for the other goalline.
As soon as i start to slow down i stop and walk to the other goalline turn and repeat.
I used to have trouble hitting the 40 without losing speed.
Now im hitting the 65 before i kinda topout and hit the goal in full stride.
Cardio in the gym is to boring for me.