I always say resistance training because when I say weight training People tend to think Arnold lifting ,,,
I use both machines , dumbbells , barbells , bands etc... any weight baring exercise ... my story is I got vsg in a June of 2016 , I have always trained with weight since 2007 so before my surgery I did heavy abs workouts with ball, machines etc.. think that is what help with not having any extra skin , I am 55 so a little harder to lose weight and maintain but my rountine is for longevity , my rountine , is I work out at gym after work. ( I sit down all day) Monday , Wednesday and Fridays , 1hr weights , 30 min elliptical, tues and Thursdays some sort of leisure cardio with friend 3 mile walk , or a long bike ride , Saturday at 6 or 7am go to the gym and I do a c25k for 30, light weight training on muscles did not work during weeks and end with a 30 min cardio be it elliptical or stair climbing or some other machine , they have Netflix so I just do something and watch a 30 min show .. I try to do a rountine that I will do for the rest of my days. I make sure I do at least 2 days of training a week , anything over that is gravy . but I make sure I at least do mon and wed , I schedule stuff around those days so no excuse ,,, seems to work , i am also a personal trainer so I have about 4 clients right now but when I retire I will pick up more.. but all in all bottom line is weight training , resistance is a must and should be kept in your routine