Or we can call it Strength, give it the 0-10 balls but make it ridiculously slow to train, although a bit quicker for youngsters. Give youths varied amount of balls, up to maybe 7 or 8.
The skill would come at a cost though, speed would be affected, a muscular player would be a bit slower. So training above, say, 5 would start to cause speed to cap. 6 balls may make a player max at 9 speed, 7-8 strength at 8 speed, 9 strength 7 speed, 10 strength 6 speed. So it would give a new variety of tactical choices, do you want a defender who'll bull dose a pacey striker all day long? Or do you want a defender who's very quick, but would fail against Akinfenwa?