Fast or slow, there's nothing like running to trigger the release of feel-good endorphins and to lower stress hormones, cholesterol and blood sugar. Alas, while running can rev up your metabolism like no other exercise, its toll on the musculo-skeletal system becomes more apparent with age and injury.
Perhaps you're an avid runner temporarily sidelined by injury. Or perhaps you were once a light jogger who long ago hung up your running shoes because it did a number on your lower back.
All is not lost. Low-impact exercises such as swimming, cycling and other activities can provide the same aerobic benefit as running without the wear and tear that a bi-ped pounding vertically along the pavement absorbs.
Swim Your Way to Stamina
Swimming deserves its reputation as a near-complete exercise regimen. It's a full-body workout that strengthens and stretches muscles, increases lung volume and builds stamina. What's more, different strokes use different muscles, so you can always ramp up the intensity by trying a new stroke that will challenge your body in different ways. One of the great things about swimming is that the worse you swim, the more of a workout you get — just make sure you swim well enough to keep your head above water before you jump in.
Rock out with Rowing
Rowing machines aren't the most popular machines in the gym for a fairly obvious reason: they provide a totally butt-busting cardio workout. Rowing activates muscle groups from the back of your neck to the tips of your toes, providing resistance training and getting your heart rate well into the cardio-training zone. ACE Fitness suggests starting on a setting of from 3 to 5 and working up from there.
Cycle to work -- or anywhere else, for that matter -- and you're likely to live longer and better. A recent study by the University of Glasgow of a quarter million cycling commuters found that their chosen method of transportation cut risk of death by cancer and heart disease by almost 50 percent.
Hit the Elliptical
Like stair machines, the Elliptical simulates a climbing motion and makes you work against gravity. In contrast to stair machines, the Elliptical's two pedals work in more of a gliding motion that makes it a bit more mellower activity compared to running. Ellipticals are criticized in some quarters for pampering the user, but that's exactly what makes them a great choice when faulty ankles, knees or other considerations are keeping you from running.
Try High-Intensity Interval Training
High-Intensity Interval Training (HIIT) is a method of aerobic training in which you alternate short bursts of high-intensity activity — at 70 percent or more of your max — followed by longer intervals of rest or low-intensity activity. It's a way of turbocharging your cardio time that yields big payoffs. In fact, HIIT has been shown to improve insulin sensitivity, lower blood pressure and burn subcutaneous fat more than the same exercise performed at full throttle. You can apply the HIIT technique to all of the above exercises.