The more I observe people trying to stick to a fitness program, the more I realize how important it is to customize a program to one's level of commitment, fitness level, age, budget, and available time.
I figure if Bruce Lee could make up his own martial art of Jeet Kune Do which was a hybrid of other marital arts based on his personal philosophies, then we should be able to do the same with our fitness too. I don't have as cool a name for mine; I just call it customized fitness.
I get a kick out of the saying "you are unique... just like everybody else", but it is true that we all are unique in that we all have different goals, abilities, and preferences. Unless we take these differences into consideration when developing a fitness program, we are setting ourselves up for failure.
When it comes to nutrition, I see advantages to Paleo eating, but I also like aspects of a vegetarian diet. I try to avoid junk food, but I'm still guilty of occasionally eating high-calorie and low-nutrient foods. I try to only eat those foods in moderation or on special occasions. I've adopted aspects of various nutritional philosophies that sometimes contradict one another and I've applied them in a customized way that works best for me.
When it comes to exercise, I do the same thing. I like traditional sports but also appreciate aspects of Crossfit training and lifting weights in a traditional body building type of program. I've cut back on my long distance running because my knees don't hold up if I run more than 10 miles. I prefer shorter 5K races that don't take such a toll on me. I love playing basketball, and I could easily play a couple hours every day if I had that much free time. Since basketball is my favorite activity, it is at the center of my work outs, and I schedule other cardio and resistance training activities around it throughout the week.
Is there a specific sport or activity you really enjoy? Even if it is not recognized as the greatest all around work out, I'd still encourage you to stay active by doing what you love and then trying to incorporate other conditioning aspects you may be missing into your routine. I still think someone who gets out and walks with friends everyday will have greater success in the long run than someone who attempts a more comprehensive program if it is going to be too difficult or complicated for them to adhere to.
There are many different philosophies out there when it comes to exercise, nutrition, and fitness. I try to incorporate as much truth from each one of the various disciplines that I can. I also try to adapt them to my personal circumstances, which may be less than ideal in many instances. If you fear starting a particular program because you don't think you will be able to stick with it, then it is important for you to customize a program to your unique circumstances in order to persist and get long term results.