There are any number of ways to repair diastasis - the goal is to bring the separated muscle edges back together... and do it well so that that they STAY together! .
I personally like using barbed suture, it allows me to set my tension and I don't have to worry about knots coming undone or being potential sources of infection. .
From a patient perspective, this is the part of the surgery that will give you back your waistline (think INTERNAL CORSET), but is also the part that will be the most uncomfortable during recovery. I encourage my patients to work on building their core before surgery - it really makes a difference having a strong foundation!