If your knees are injured, you are overweight or just need a break from running, here are some non-impact cardio options that I prefer to do.
blog.pdf
12 Low-Impact Workouts That Really Pay Off
Low Impact Cardio Exercises: 6 Workouts to Try at Home
Low-Impact Exercise: Benefits, Types, Tips, and More
The Best Exercises for When You Have Low Energy
The 9 Best Low Impact Workouts That Still Burn Major Calories - FitOn
PDF) High Impact Exercise Training Versus Low Impact Exercise
Kettlebell and Cardio Pick-Me-Up – Wellbeing with Avery
Movement is Medicine: Best Low Impact Workouts