I did wonder but the answers given show that it must be dumbell because your not gonna barbell below 5kgs, 6-16kgs etc....
17-39kg must be very few reps and looking for ultimum muscle mass...
6-16kg is your average lifting weight, many reps for teens through to adults. doing over 40kg is just sick

theres 50kg dumbell's at my gym and just lifting it off the rack is a start

let alone ONE arm pull ups
and lifting weights and powerballing wont work in sync, like saying to a bodybuilder "Here's a powerball, spin it as fast as you can" garanteed he wont get it over 12k first time.
GILPI

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