An improvement goal in general is getting better, doing more, working harder, developing new skills, learning something new. Some examples of improvement goals are to walk one more minute, do 5 more crunches than the day before, learning a new stroke in your favorite sport or trying out a new piece of exercise equipment.
Improvement goals are not as rigid and general as making a goal to exercise three times a week for 60 minutes each time or setting a short time frame to say, run a marathon. Unless you are already in the habit of exercising very closely to those goals, then you are setting yourself up for failure.
When you set small improvement goals for yourself you are setting yourself up for success instead of failure. You could try to do one extra crunch each day instead of assigning a number, like trying to do 50 when you haven’t done more than 10 in a row for the past 15 years.
You could make a goal to try, simply try, a new piece of exercise equipment at the fitness center each week, without attaching any number or minutes on the attempts.
You could pick out a new sport to learn or a new skill in a sport you already do and make the goal be realistic, like learning one new sport or skill per year.
By trying to do just a little bit more each day or each week then you are more able to listen to your body and be flexible. You can take a day off if you get sick and not fail. You can modify your goals more easily because they are more realistic to begin with.
Lastly, improvement goals almost guarantee that you will not be comparing yourself to other people. When you compare yourself to other people you are will fail at some point, since you will always be able to find someone who is better than you in some area or another.
So focusing on yourself and your own slow realistic improvement is sure to make you successful in your exercise program.