What is the quickest way to get a 6 pack without a machine?
If you have very little body fat as it is, then doing various ab exercises like bicycle crunches is fine. Make sure you do oblique exercises to, to get your sides. Also, lying on your back and raising your feet about a foot off the ground and slowing lowering them again, keeping your legs straight, is a great way to work out your lower abs, repeated about 50 times. However, if you’re trying to burn fat, then just doing crunches won’t help. The best way to burn fat is to do daily cardio workouts. Running or jogging for 20 minutes each day is good, or picking up a sport like basketball, or swimming, are all good ways to get your cardio. That said, don’t put too much pressure on yourself to have a 6-pack, especially in such a short amount of time. You could get the effect of a “crash diet” where all the weight is gained back quickly. It’s great to want to be healthy and fit, but just don’t take it too far. Good luck.