Vary your ab crunches with some regular sit-ups.

[Erica White]

Look for another bench option if you can touch the material that is under the pad.Profactor T-2000 Vary your ab crunches with some regular sit-ups. Sit-ups may be dated, but they still offer plenty of benefits. There is one caution that you should be aware of; stay away from anchored-feet sit-ups.
http://www.supplements4us.com/profactor-t-2000/