Before I give you advice I want to know a few things:
1. What are your personal goals?
2. What are the "other" parts of your fitness program?
3. What is your diet like? Have you determined your approximated calorie needs?
4. In your view, what does performing "sit-ups" correctly, do for you and for your goals? What is their "purpose?".
Best wishes,
Chillen
Sorry I am late replying to this.
In answer to your questions:
1. I want to both lose weight and build muscle all over my body. I am 6'0" and I weigh approximately 235 pounds. According to my primary physician, the ideal weight for my height is somewhere between 180 and 190, if I remember correctly. About 3 years back I was much better off and I was at about 190 lbs. This means that I have gained 45 lbs since then and it is very embarassing and uncomfortable and I feel a lot worse than I used to, for obvious reasons. The places that I really want to get rid of the fat are my chest, stomach, lower back, and thighs.
2. Currently my fitness program is: 100 sit-ups per night, 50 push-ups per night, and then either jogging for 2 miles or biking for 6 miles per night. Also, I do not stretch before I work out because I heard that it is bad for you. I used to stretch before I would work out but then I quit doing it after my friend told me not to. Is it true that stretching is bad for you in some way? Do you stretch, and if so, why? And also would you recommend I change anything about my current fitness program and why?
3. To be perfectly honest with you, my diet could be better. I have not determined my calorie needs. How can I do that? Basically, my diet isn't terrible as far as I know. I eat lots of fruits and vegetables but I am also pretty bad when it comes to snacking on junk food and the occassional pizza and/or fast food hamburger, but I wouldn't say that I go overboard with it. What would you suggest I do?
4. Very good question. Basically, what I want to get out of these sit-ups is weight-loss and muscle building in my stomach and maybe a little bit in my lower back region as well. I want to look better and feel better overall. I also need to know what kind of exercises I can do to get rid of chest fat.
Let me just say that I will do anything and I mean ANYTHING to get back in shape and build muscle. I am a pretty motivated guy when it comes down to it and I plan to work hard to achieve my goals. I am a 24 year old male by the way, if that info helps at all.
By the way, not to sound too flattering but someday I would really love to have a body like yours in that picture, or at least similar. That would be my ultimate dream actually. What does your fitness program and diet look like, if you don't mind me asking?
With no weight and just the hands, no, not necessarily.
However, some can perform (or attempt to perform) a sit-up incorrectly, and IMO, can put too much stress on the neck. I know some can do it without problems, but it just doesnt settle with me well.
More importantly......plate weight does NOT belong behind the neck....I think it makes sense, young man.
Additionally, some can miss the point about the hip flexors and focus of various core exercises.
Let me give you an example.
Anchor your feet (on something heavy), and perform a half-up thirty degree sit-up (with whatever weight you are using at this point in training--ON CHEST--PLEASE

, LOL)
Next......
DO NOT anchor the feet on ANYTHING.......
But bend the knees slightly and perform the same sit-up I described.
You will see a difference.
How do I know? Because I have made many mistakes in the gym, recovered from my errant ways, went on, and corrected myself as I went on with my goal.
Its a learning process.
And it doesnt stop.
ROCK ON!
Train hard........
Be at your best!
Chillen
Very interesting indeed.
When I used to do sit-ups I would anchor my feet under a sand bag. Was this a bad idea? I am afraid that I may have taken my focus off of my abs because of this. Do you think this is possible?
And just to make sure, you ARE saying that it is better to do sit-ups without an anchor on your feet, right? It is better for the abs (and not the hip flexors which I don't want to focus on with sit-ups), right?
By the way I have been doing sit-ups differently than you described.
Well, I put my hands over my chest, so that is good I suppose. But I never did the 30 degree sit-ups. I would actually go more like 90 degree sit-ups or maybe a bit more than that actually. Is that bad or good? Is 30 degrees the best way to do them?
Ah! Well. I feel kind of dumb. But it feels nice to correct a mistake
Plates behind head DEFINATELY not a good idea of course! I hope no one would get the wrong idea from my post. But thanks for clearing that up
Hey man don't feel dumb. Seriously. I don't think anyone will get the wrong idea from it at all.
The ones who admit that they don't know everything are the smart ones. If you say you know everything then people will be less likely to help or correct you and then you'll never learn.
I am here to learn and let me just tell you that I don't know ANYTHING so I will be asking a lot of "stupid" questions, but I can guarantee that I will learn a lot more than the folks who sit there and are too afraid or embarassed or proud or whatever to ask the tough questions.
By the way thank you for your input in the thread. I appreciate everyone's opinions and experiences.