The ab shredder isn't so much a specific workout as it is a concept. It consists of combining direct abdominal work with metabolic exercises. I started using the approach with figure competitors after reading the article, Spot Reduction is Real, by Dr. Lonnie Lowery.
By using an ab exercise to increase blood flow toward the region, you'll increase fat mobilization and transport more of it away from that area. This will lead to using a little bit more fat from the abdominal area when you're doing your cardio.
So you'll do ab work, then do a bout of cardio, then go back to the ab work, then cardio again. Continue going back and forth for a specific amount of sets. I use several versions depending on the fitness level of the individual as well as his or her psychological profile.
- A1. Swiss ball crunches with a slow squeeze-rep style: Make each rep as hard as possible. Go up and down slowly, squeeze hard every inch of every rep. Do as many reps as you can. Then rest 20 seconds, do as many reps as you can again, rest one last time for 20 seconds, then do as many fast reps as possible. Take as little rest as possible.
- A2. Farmer's walk or Zercher carry: After the crunches, walk for 60 seconds holding dumbbells or a barbell Zercher-style, as shown below. The goal is not to cover max distance in that time period, it's to walk while keeping the core as tight as possible; imagine getting punched in the stomach.
- A3. Any cardio machine, all-out for 30 seconds: Use the elliptical, stationary bike, Assault Bike, rowing ergometer, etc. After the 30 seconds are up, rest for a minute.
That's one interval and you do 4-5 in a workout. It's very effective and "non-boring" (as much as energy system work can be) with the added benefit of leading to slightly more abdominal fat loss.
Option for competitors: If you're nearing a contest, try adding 20 minutes of steady state cardio at the end. If you do this, make the cardio its own workout since it'll last around 40 minutes. If you're doing it without the steady state cardio, you can do it at the end of a regular training session or in a separate workout.
Normally I introduce clients to the abs shredder with a simpler workout:
- A1. Swiss ball crunches: slow, squeeze-rep style: Make each rep as hard as possible. Do as many reps as you can, rest 20 seconds, do as many reps as you can again, rest one last 20 seconds and do as many fast reps as possible.
- A2. Cardio machine interval: doing 15 seconds moderate intensity/gradual build-up, 30 seconds all-out and 60 seconds moderate intensity. Rest 45-60 seconds. This is one interval. Do 4-6 total.