So lets set the record straight. No particular exercise is going to make your abs look like Ryan Reynolds's or David Beckham's. Each person's muscles are arranged in a way specific to that person. The only power you have is to make a muscle bigger or smaller. You can also make your abdominals more visible by decreasing your body fat percentage. But you cannot change the shape or arrangement of your muscles. This is the body that God gave you so accept it.
So now that I am done with that rant I would like to talk about training what I call the "Core". Depending on who you talk to there are many different definitions of the core muscles. In my definition I define the core as the muscles that connect the lower body to the upper body. I define the core this way because (1) there are a lot muscles in that area, (2) most of the muscles work together to perform movements or to stabilize, and (3) it establishes the idea of a group of muscles and not just a single muscle. All of the core muscles work together to protect the spine and internal organs, transfer force throughout the body, stabilize the torso, and provide a stable base for the extremities. Having a strong core is important for health and longevity, reducing risk of injury, and also maximizing performance in almost all activities. In many strength and conditioning programs the focus is placed upon building core strength first then moving outward. If your body was a house then your core muscles would be the foundation. If your core is weak it effects everything else. So what is the best way to train your core muscles?
There are endless ways to train the core muscles and no way is the absolute best. What works for one person could cause injury in another. Regardless of the routine though, the focus of any program should be to maximize safety and optimize performance. So with that is mind the easiest and most basic way to train the core to perform functional exercises. This includes exercises performed standing on your feet, exercises without seats, benches, or stable surfaces, and exercises that utilize large muscle groups. Examples of these exercises include squats, lunges, deadlifts, pushups, pullups, rows, and shoulder presses. If you performed nothing but these exercises, with proper form, while standing and without assistive devices (seats, benches) then you would have a reasonably stable core. However, if you have the time and the energy it is a good idea to focus on specific core exercises to optimize strength and stability.
So here are four movements/exercises that address all of the core muscles and planes of movement within the body. Since a key function of the core muscles is to resist movement many of the exercises require you to hold the torso rigid and in a neutral position while the extremities move through space. This is a very safe and functional way to train that addresses the two program factors mentioned previously. So let's do it.
This is the most basic of all the core exercises. It is considered an anti-extension exercise because your muscles are preventing your spine from extending. I love it because it is safe and effective, hits all of the core muscles, and requires no equipment. Just remember to keep a straight and rigid body through out. Do not let the hips sag down as this places stress on the lower back. If you do feel the hips lowering then terminate the set at that time. Start with 15 second sets and gradually increase to 90 second sets.
This exercise is probably the most functional and transferrable to daily activities. It is considered an anti-lateral flexion exercise because your muscles are preventing your spine from bending/flexing to the side. You simply pick up in object, hold to your side in one hand, and walk a determined distance. Twenty five to fifty yards is sufficient enough. Just remember to tighten the core muscles like you are about to get punched in the stomach, stand up tall while walking, and work both sides. You can use dumbbells, kettlebells, or even buckets of sand or water.
This is a great anti-rotation exercise. It does require some equipment, though, so you will need either a cable machine or a resistance band. To perform this exercise you stand perpendicular to the cable/band and hold it at chest level with both hands. From there you press straight out from your chest. The further out you press, the more the resistance will try and rotate your torso. The objective is to maintain a tight and rigid torso, and do not let the resistance rotate you. Start with a low resistance and work your way up to a challenging 12 reps per side. This exercise can be done standing or kneeling.
This is an exercise that actively contracts the abdominals and the hip flexors. It is a very challenging exercise that places a good amount of stress on the core while keeping the spine in neutral position. There are many progressions of this exercise so any one can use it regardless of strength level. Beginners should use what is called a roman chair and should bend the knees to around 90 degrees each rep. Remember to not swing the legs at the bottom. Use a slow and controlled descent.
To progress from there you can simply keep your legs straight on each rep.
The final progression is to perform the exercise from a hanging position without back support.
There you have it. Four great exercises that will build a strong core, help prevent injury, and not damage your spine. My recommendation for implementing these exercises is to focus on one exercise each time you workout. Simply rotate through each exercise each time you hit the gym and do between 3 and 4 sets per workout. For example, if you go to the gym on Mon/Wed/Fri, you could do planks on Monday, farmer's walk on Wednesday, and the pallof press on Friday. The next week you just start Monday with leg raises. One last word of caution, if something hurts or doesn't FEEL right to you then don't do it. These exercises are considered safe but every person is different so please use common sense.