This is the the thing with core training. To really strengthen your core you need to excercise a long time, especially if you were previously a couch tater. What I am saying is start early. Train with free weights and forget machines. Squats are the strongmans must have no doubt. However, if you got a bad knee or one going and your new to training forget squats. Do lunges instead.
Here's the round about way I do it. Note: my days of hanging and banging are done. I superset (0 rest beween sets and keep my heart rate in the 150 range for about an hour =/- a day)I still do heavy lifting but do it very quickly. We are all different and our bodies respond differently. Training is like fishing for me, always have done it therfore I know hart works for me.
I train about everyday cause the way I see it that's the way our bodies were meant to go.
Day 1 back and triceps.
Seated rows
Close grip bench
Standing rows
tricep pushdowns
Lat pulldowns
one arm kickbacks
hyperextensions
someother weird isolating tricel move
core reaches
Sprint
day 2 chest and biceps
Dumbell flat bench
dumbell curls
inclince dunbbells
one are iso curls focusing on forearm
decline bench
weird isloating bicep move
flys
forarms
day3 Legs shoulders
squats
shoulder press
lunges
lateral raise
side steps
front raise
leg extensions
backward row
leg curl
neck extensions
day4 do it again, you can sleep whenyour dead!
Mosr everything is 3 to 4 sets and fast and heavy, I hate running and get my cardio here.
Do anything but be consistent. It will make you a better fishermen cause it will make things easier and less tiresome. Fact is, most can not fish enough to get the "training"they need. That is why so many who spent many years weekend warrioring it are now hurting IMHO, it just wasn't standard to prepare. Sitting in an office or truck all day and then getting beat up on the weekend, something is going to give.
But remember core takes consistentcy and time. But anything, anyday is better then nothing.