Hmmm, I personally only work with a "1 sidebar" theme and keep it simple like you have. Maybe try working with different colors for the links, and definitely test out the placements to see where you can make the most money. I would suggest you pop a 300x250 ad block to the top-left of each article.

Search boxes are used very rarely on many adsense sites I see, but I make a good bit from those search boxes so I would recommend you use that also somewhere very noticeable on your site.

The ads stick out like a sore thumb. You should change the rest of your website so all the links are blue, like the ones in the ads, not black. Also, I can tell within 5 seconds of visiting your site that there's no useful information, and there's nothing fun or interesting that makes me want to stay, so that's why other people are leaving so fast. None of your ads are highly targeted, so there's no reason for people to click on a very general weight loss/nutrition/diet advertisement, so they leave without finding an ad that looks good to them.

You are trying to do too much with this website, too broad, and it's a very difficult niche.

change adsense colours to fit the site layout
change that intro. text to be much blog like more text and streach it

wow thanks...thats a nice "Make the ads blend into your site better " i like it! i'll do it next time...being a newbie is like going to school again....but a little bit fun... LOL

With such a HIGH bounce rate that can only mean one thing, CONTENT. People are not finding appealing content in your site. You need to find ways of keeping them interested in your site and what you have to offer. Remember that bringing traffic to your site is the first step, KEEPING them there is probably the hardest. Keep in mind the following, having high traffic but a low bounce rate is not good, think of your site as an actual store, Would you rather have 100 people enter and leave your store after glancing around within seconds or 50 people come in look, admire what you have, inquire about items and possibly make a purchase because you just have so many captivating things to offer... ???

I think there is too much white. There are too many spaces. This is a dramatic suggestion, but maybe a different and darker background color? That may mean changing the text colors and links too obviously.

All in all, it's a great effort.

Maybe the site is boring? Look, I don't mean that as an insult! It's about health and fitness -- but maybe you should take it to another level and change it around a bit to reflect something more interesting.

For example: how fitness and health can make you look more attractive to the opposite sex. Maybe some stuff on what men and women look for in each other, then focus on health and fitness regimes which achieve those results. Know what I mean?

Other content ideas: healthy things to do before a date, women like buns on men, so here is what you do, etc.

I think keeping what you have and expanding the content more would bring in more people and keep people on your site.

Also, say for example after somebody reads about some great excercises, you write about the proper outfit to go with it -- then adsense delivers some ads on the page about great clothes -- maybe users will click out of your site looking for those clothes, or fitness equipment that they may need to get the perfect body, or whatever.