You can take fitness tests given by a qualified personal trainer. You might also find at-home options, such as the sit up test, pushup test, sit-and-reach test, and the 1.5-mile run. There are online articles saying what the age-related norms are for these exercises for men and women.

Regular physical activity can improve your muscle strength and boost your endurance. Exercise sends oxygen and nutrients to your tissues and helps your cardiovascular system work more efficiently. And when your heart and lung health improve, you have more energy to tackle daily chores.

You should be able to return to the same level of strength fairly quickly, typically within a few weeks. For cardio and endurance, it's a little different. A recent study found that for endurance athletes, a loss of cardiovascular fitness and endurance starts to happen after as little as 12 days of no exercise.

As a general goal, aim for at least 30 minutes of moderate physical activity every day. If you want to lose weight, keep off lost weight or meet specific fitness goals, you may need to exercise more. Cutting down on sitting time is important, too.