Everyone is able to have their own opinion on sit ups. Some say they aren't good for the spine, others say they may be the best exercise for overall abdominal development. To be honest, I'm on the fence. I don't recommend doing 200 sit ups every day but I incorporate them into my programs. Like other muscle groups, critical to train your abs with range.
5) Stay consistent. Constantly chopping and changing your routine does not allow you to monitor your progress. If you don't see progress the ease in starts to lose motivation. Performing the same exercises will also lead to greater gains i.e. consistently performing the bench press will carry gains inside of bench squash. You will have to change your program sometime, but I'd personally only have this happen 6 - 8 weekends.
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