Is it OK to do cardio on rest days?
The short and simple answer to this is yes, you can do cardio on rest days. It is a commonly held belief that if you do cardio, you will 'kill your gains', meaning you will break down the muscle you have worked so hard to build. However, if you are smart with your training this won't happen.
Do lungs need rest days?
The heart and lungs never take a day off. The days you are not in the gym lifting, the heart and lungs are still working. It is what they are designed to do. So, by training them or giving them a workout every day, the overall benefits to the body are tremendous.
Is it OK to take 2 days off from cardio?
Taking a few days off will actually do more to improve your fitness and training. Typically, I recommend that people take a few days off from exercising every six to eight weeks, assuming you work out at a good intensity and are consistent.
Is 1 hour of cardio 3 days a week enough?
Now, cardio. For weight loss, the National Institutes of Health recommends at least 30 to 45 minutes of moderate-intensity exercise three to five days a week.