try this circuit training,go from one exercise to the other without rest.
1-versa climber 5 min
2-ab crunches 25 reps
3-step 10 min
4-ab knee ups,one set to failure
5-wave,side glide,10 min
6-lower back,hyper extension,one set to failure
7-cycling,10 min
8-ab sit ups,30 reps
9-lower back,hyper extension,one set to failure
once you are done,you can curse me,ha ha.