Even when you start out with baby steps, such as the C25K program, you need to do the work and trust the program. So many people become disengaged and too easily give up on the effort. Why? Because they don't think they will complete, so wasting 9+ weeks and having nothing to show for it seems ridiculous...giving up early is too easy.
Erin has just started the C25K program. She is in week 4 and is dying (not literally). She thinks she's failing because its still so hard. She's ready to quite. So, what did I tell her? Quite simply, I told her to do Week 2...just one day. She needs to do this to prove to herself how far she's already come. She can easily do a day in Week 2's training and sail through it easily! Only when you step back do you ever realize how far you've come!
What does this give you? If gives you a sense of accomplishment when you need it most. It gives you a sense of purpose, that moving forward and pushing yourself will get you there. And, it gives you a sense of pride.
Trust in your training plan. It may not be the best, for you...but it will get you where you need to be. Once you are there, you will have a better sense of what worked for you and what didn't and then you can tweak that plan or ditch it and grab a new one entirely. But, its worth it...stick with it and reap those rewards.