This is not the way strength training is meant to feel - it is meant to feel different from cardio.
Strength training is supposed to be done in a slow and controlled manner, and typically you will just feel you cannot do another rep with the correct form. Doing crunches for as long and fast as you can in the way you might do cardio, is NOT the way you are meant to be doing them.
Crunches are done improperly more often than any exercise other than squats. A proper crunch only lifts the upper torso a matter if inches from the floor, is held at that point as an isometric contraction before a very slow controlled return to the floor position. A pause at the floor position and another slow contraction is initiated to raise the upper torso. Not doing the isometric contraction, a fast return to the floor position and a bounce back to the next contraction are common errors. Even done properly this exercise will only strengthen the abdominals and provide no strengthening of the complementary muscles of the back which have to be strengthened for a proper core.
Rather than doing weighted crunches add a weight to the back when doing planks and hold the plank longer.
Fitness Minutes: (23,579)
3/11/13 5:04 P
All right, thank you guys. I use 30 lbs with the machine, but if I don't, I don't feel the burn in my stomach. I don't get it, I'm doing something wrong then. I'm going to try to do crunches on the floor and Pilates exercises in conjunction with the machine, that way I'll strengthen more of my core. I love Pilates. I don't think I can do the decline crunch with the plates, though.
My sport is all about core strength so I can't just do planks and call it a day, and I see nothing wrong with using a variety of exercises to strengthen these parts of the body. I use this machine too once in a while since my gym happens to have it. I've noticed the same thing though in my case it only happens on the last rep -- which leads me to believe that you may have the weight set too high. Try reducing the weight and see if it helps.
If you want to do the equivalent of this machine without the machine, one of my preferred exercises is to put a decline bench on a steep decline, get on the bench with your feet in the pads, and load plates onto your upper chest. Once the plates are in place, hug them and do crunches til your elbows touch your knees, then back down til your head touches the bench. This basically accomplishes the same thing but you won't get back pain, I don't think - I never have. Incidentally I do about 80 lbs on the ab crunch machine but only 45 lbs of weight plates added!! So definitely go easy on the weight plates at first -- you might not need as much weight as you think!
3/11/13 1:52 P
Are you adding weights to the machine? You may be using too much weight or extending your range of motion too much. Best to have a train check your form.
If it hurts then don't do it. Machines regardless of their supposed intended purpose create artificial movement and cause muscle imbalance.To work your core lose all machines and do planks, bird dogs and side planks. Forget any situp or crunch type exercise they only work the abdominal muscles and you want to work your core both front and back muscles equally.
3/11/13 1:36 P
I agree that it's a good idea to ask a trainer to check your form if possible. I also wanted to mention that planks are a much more effective ab exercise, so I think you could skip the crunches completely :)
you may not be. But if you don't mind using the machine, I suggest you pull one of the staff from the gym to ensure that you are using it correctly. Maybe you are adding too much weight or not enough. Maybe you aren't putting your feet in the right position. I had a similar issue when i first used it. One of the trainers saw me and corrected my form.
3/11/13 12:00 P
Yes! I don't use the ab machine at our gym for the same reason (same for my hubby) but it doesn't have the leg raise. We have started going to a personal trainer once a month that has physical therapy-type strength machines (med-x) and we can use that ab machine no problem. Try limiting your crunch to only 90 degrees and see if you can do it without the leg part?
Otherwise I would recommend doing crunches on the floor- wedge your toes under something, cross your arms in front of you, and come up about 40-45 degrees off the floor. Go down and touch completely before you do your next one. Rest for 10 seconds after your first set.
Fitness Minutes: (23,579)
3/11/13 11:14 A
I noticed that when I use to Ab Crunch Machine, my back hurts in an unusual place. It's the one you sit upright in, and it has handles above your shoulders and you can add extra weight to the machine, and your legs go behind a bar. When you pull down, the legs go up, so it's like you're doing reverse crunches as well as a regular crunch. Does any one know what I could be doing wrong to cause back pain in my low back at the curve of my spine. It's not real painful, just achey. I have back problems, but I Never get pain in this spot until I used that machine. I am going to the gym tomorrow and I am going to ask a trainer, but does anyone else have experience in having pain after using this machine? How did you correct the issue? Am I doing something wrong?