This program requires some sort of resistance, although it doesn’t have to be a set of dumbbells. You can use any household item of equal weight, i.e. canned food, water bottles, wine bottles (don’t drop them…). If you have a set of 1-5kg dumbbells, great! If you feel your weight is too light, you can increase the reps (50 becomes 100, 20 becomes 40). Don’t forget to warm up and cool down, enjoy!