Free weights are the best weights.
They are personally responsible for the results of most of the famous body builders today and in past times.
Free weights are used for any part of the body, including abs.
Let me show you a few great workouts for getting a defined six pack using free weights.
Every time I go to the gym I use free weights.
I never use machines and I never will.
I tried some machines in my time but most of them are crap.
They just don't give you the same hardcore workout that free weights do.
Here are a couple of my favorite.
1.
Front squats: These are when you load a barbell up with weights and you hold it across the front of your shoulders and do squats like this.
Very effective at targeting the abdominals and getting a good burn.
2.
Weighted sit ups/crunches: These are just done as they sound.
Normal sit ups or crunches, just with a plate of weight on your chest that you hold onto.
Great for the extra burn in the abs! 3.
Leg raises You can do these lying on the ground and keeping your legs straight, slowly raise them up and down.
Or...
if you are feeling hardcore you can hang from a bar and slowly raise your legs up while you are hanging.
If you can't quite do this one, I don't blame you.
Hanging knee raises are a little easier but still give you a darn good burn and a great result.