Carl wants to improve his physical appearance without changing his weight. He has no restrictions as long as he uses his albuterol inhaler. The exercise prescription includes cardiovascular activity like walking and running 3-5 days a week for 30 minutes, strength training 2-3 days a week doing 3 sets of 15 reps of exercises at over 50% heart rate, and flexibility exercises 3-5 days a week holding stretches for 30-60 seconds. The prescription follows FITT and PROS principles of progression, regularity, overload, and specificity to safely improve Carl's strength, endurance, and appearance over time.