Weight-bearing squat is to carry a barbell on your shoulders or hold dumbbells in both hands, bend your knees and squat slowly until your thighs are parallel to the ground or slightly below your knees. After holding, the quadriceps will contract hard and kick your knee to recover. Action rhythm: squat for 2 -3 seconds, stay still 1-2 seconds, squat for 2 seconds. If you don't use barbells, dumbbells will do. 20 Jin dumbbell is not heavy. You can do more than 8 groups 15~20.