Karl is a friend who hikes a local trail almost every day. The trail is not easy, ascending 300 feet in the first quarter mile alone. Uphill stretches push the pulse and breathing rates up; downhill stretches require strength, flexibility and balance. Karl is 83 and he has maintained his physical fitness with functional activities like hiking and skiing. His old friends in the valley no longer hike with him.  “It is sad,” he says, shaking his head. “They didn’t need to stop and now they can’t do it anymore.”  He is right – fitness requires doing.

Why bother staying fit?

Physical fitness is worth preserving. It makes aging easier and more enjoyable, prolongs independent living and accessibility to many pleasurable activities, and lessens dementia risk. It raises insulin sensitivity, reduces blood pressure, cuts weight and improves cardiovascular risk factors.  You needn’t be an athlete to be fit and, as Karl demonstrates, fitness does not require gym memberships, classes or travel to and from a sports facility. And as many researchers have demonstrated, simple activities such as walking and running have positive effects on body and mind.

What does running do for you?

Much information about the beneficial effects of running comes from studies done in high level athletes. This sports oriented literature can be bewildering, leading into a thicket of terms like periodization and lactate thresholds and specialized measurements like aerobic capacity and heart rate variability. But buried in the details of these studies are useful facts that, when simplified, provide guidance that will improve the fitness of beginners and people who already have a stable exercise habit.

Why walk too?

While running promotes faster weight loss than walking, both lower blood pressure and improve heart and lung function. Walking requires more of the shin muscles and running more of the gluteals and quadriceps. Both are worth incorporating into a fitness program because of these different patterns of leg muscle use. Balancing the strength of lower and upper leg muscles and improving flexibility of all of them lessens strain on knees.

How much of each?

The balance between walking and running in an exercise plan depends on beginning fitness level and on goals.  For a sedentary individual unaccustomed to exercise, regular walks will be enough to increase fitness, at least in the beginning. For someone who has run in the past but not recently, a combination of walking and running is a good way to start. And for someone who has a good level of fitness and a long running history but is getting older and accumulating aches and pains, the addition of walking balances leg muscle groups.

Short periods of intense effort pay off

For all groups, the introduction of short bouts of more intense walking or running into a regular exercise program is perhaps the most important aspect of maintaining and improving fitness. These “intervals” provide the challenge that the heart and lungs need to stimulate their capacity to provide blood to working muscle more efficiently. A recent study from Denmark provides good evidence that a very small amount of time spent running faster improves fitness. It also decreases blood pressure and makes routine running more efficient. In the study, the addition of an interval program of faster activity, performed twice a week, was not only well tolerated but study subjects stuck with it and benefited more than they did from other seemingly more difficult programs.

In the Danish program, a short warmup is followed by two five minute segments separated by a 2 minute rest, and followed by a short cool-down walk or run. The five minute segments consist of running comfortably for 30 seconds, harder for another 20 and as fast as possible for another 10 seconds, and repeating this pattern 4 more times. A walker could try the same pattern, with effort judged by breathing rate and difficulty and by the ability to complete the 5 minute segments. As improvement occurs the segments cover more distance.

Change the terrain

Other ways to increase effort include walking or hiking uphill and climbing stairs. The important thing is to build in some segments of exercise that require more effort and cause faster breathing into at least two periods of exercise a week. In addition, going “off-road” on dirt and rock and sand requires use of little balancing muscles and improves strength and balance.

How much is enough?

How much weekly exercise is necessary? One figure quoted frequently is 150 minutes – less than half an hour a day. The payoffs though, depend on demanding more of the heart and lungs during those times than during routine life. Ambling up the street at the same pace as you walk between the couch and the TV will have less effect than but walking briskly, to the point of feeling slightly short of breath.

Can people who have arthritis walk and run for exercise? For the most part stiff joints feel better with movement. If walking or running gets easier as the joint is “warmed up,” the joint stiffness and discomfort are most likely related to shortened muscles and tension on their tendons, not to joint pathology that will get worse with activity.

Make sure you remain able to get up and down from the ground

For overall fitness, some time also needs to be devoted to strength and flexibility exercises. Pilates exercises, yoga practices, weight lifting and core muscle strengthening exercises like the TRX programs all improve muscle strength and flexibility, enhance walking and running ability and contribute to improving balance. The ability to get up and down from the ground indicates a lot about these non-cardiovascular aspects of fitness, and every effort should be made to make certain this ability is preserved over time.

Mind over matter

The most difficult part of beginning or sticking to an exercise plan is often in the mind rather than the muscles. When Karl says his friends didn’t need to stop hiking, he means that they stopped pushing themselves before there were any compelling physical reasons to stop, and then one day they no longer had the ability which he has so far maintained. His example is inspiring.