
for example I plan to lift 300lbs 3 sets 6 reps in deadlift
so I do 3 warmup sets: 1 set: 50% x 6 reps , 2 set: 70% x 3 reps , 3 set: 90% x 1 and then rest and 3 work sets of 6
is that correct?
and as for bench press 200lbs , two warmup sets:
1 set: 50% x 6 reps , 2 set 80% x 3 reps and then 3 work sets of 6
correct?

There is no correct way. It's just what works for you. I get warmed up with some stupid like door cable hookup thing like the tower 200 but mine was 20 bucks lol. It's worked great for me just for warm ups (stretching as well as getting a small pump)
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