Health and fitness goals are a double edged sword, on the plus side there is nothing stopping you achieving your them. It is you who has the final decision on almost every choice around your goals. Contrast this to other areas of life where it could be your boss selecting who gets the promotion, a customer if they should buy your product or the kids choosing to be angels or anarchists.
While having full autonomy over your success sounds good the double edge comes because no one is forcing you to do anything. As the only person to answer to you may easily not reach the standards you set for yourself.
One way around this problem is to double up on your goals. While most people are motivated by a change in body shape or an improvement in health as their main focus progress becomes easier if you have a secondary goal, such as a fitness challenge.
This is even more powerful if another person is involved. What will happen is that on some days where you really don’t care about your main goal and think to yourself, “Oh forget this, I am going to quit”
Your secondary goal will often come to the rescue and remind you, “but what about your 10km run, you and Lisa have to run it”. This will often give you some newfound enthusiasm to push things forward once more.
For me I have both the goal of returning to the fitness model stage and performing in Samba shows. Many times I think I want to quit as the fitness model shows are so far off but then I would remind myself about performing in Samba at a upcoming show. This would refocus my mind.