it should be ok, but add deadlifts in. other than doing leg extensions to train your quads, do hams excercises as well. must be balanced in your legs. dont forget upper body

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age: 13
height: 5"2 / 157cm (dream height 175cm)
weight: 80 pounds/ 35kg
standing vert: 24 inches (never trained before)
running vert: 25 inches (same thing above)

aim:
1.standing and running vert 30+ inches
2.get the vjb
3.become a centre in my school team cos the tallest centre we have is only 170cm ... dots