Possibly. Or it could be blood pressure issues.
you will lose on average 150 calories doing 230 sit ups.
a long time. few weeks perhaps
By doing sit ups.
no i have been doing them my hole life and i am six foot
no. in moderation they are perfectly fine.
doing push ups and sit ups
Yes, you get abdominal muscles.
push ups pull ups sit ups jumping jacks
yes you will
yes
yes thet can
Every one has 'abs' to start out with. Though, to get tight abs you need to do sit ups and other exercises. You cannot get tight abs without doing sit ups or any other form of exercise.