When you’re doing cardio workouts on equipment like a treadmill or elliptical, don’t lean too much on the handrails. This reduces the amount of weight you’re putting on your legs while you work out and means you’ll burn less calories. It also means you won’t get the full muscle building effect from the work out since your muscles won’t be working as hard.
It is best not to work out when your are ill, unless you only have a slight cold. Reserving your body’s energy when you are ill, will help the healing process, and get you back to full strength quicker.