FITT stands for: fitness, intensity, time, type of exercise. Use this methodology to design a fitness program for the following client: Tim is a 45-year-old man whose goal is to improve his cardiovascular fitness and lose 10kg. He currently is not doing any exercise and works in an office. He is a member of a gym (but doesn’t use it regularly) and when he was younger he enjoyed racket sports.

Sure, here's a fitness program for Tim using the FITT methodology:

1. Frequency: As Tim is currently not doing any exercise, it would be best to start slow. He should aim to exercise 3-4 times a week. This will allow his body to adjust to the new routine and prevent any potential injuries.

2. Intensity: Since Tim's goal is to improve his cardiovascular fitness and lose weight, he should aim for moderate-intensity exercise. This could include brisk walking, light jogging, or playing racket sports that he enjoyed when he was younger. He should aim to reach around 50-70% of his maximum heart rate during these activities.

3. Time: Each exercise session should last for at least 30 minutes to an hour. He can start with 30 minutes and gradually increase the duration as his fitness improves.

4. Type: To improve cardiovascular fitness, Tim should focus on aerobic exercises. This could include treadmill or elliptical training at the gym, swimming, or playing racket sports. He could also incorporate some strength training exercises to help with weight loss and improve overall fitness.

Remember, it's important for Tim to start slow and gradually increase the intensity and duration of his workouts. He should also consult with a healthcare provider before starting any new exercise program.