Exercise needs to be something you enjoy.
Don’t join a fitness club just because they’re offering a discount if you know you hate going to the gym, but feel you ’should’. Don’t go swimming if you don’t like it just because you’ve heard it’s good cardio exercise.
This is really important if you are to achieve your goal of increasing your level of fitness. The type of exercise you select needs to be something you genuinely enjoy doing.
The right type of exercise will be the activity you most enjoy doing. If it’s jogging, go and buy some decent footwear and get going. If it’s tennis, go and buy a new tennis racket and dream of winning Wimbledon. Whatever gets you up and out, that will be the activity that will improve your exercise fitness levels more than any other.