Can exercise extend your life?

Exercise provides a remarkable variety of health benefits, which range from strengthening bones to positive effects on mood and helping to prevent chronic illnesses such as diabetes and heart disease. Research dating back to the late 1980s has consistently shown that aerobic fitness may help extend lives. Yet a few studies on athletes examining whether habitual vigorous exercise might harm the heart made some experts wonder how hard people ought to push when exercising (see here and here).

Do cardiorespiratory fitness levels affect longevity?

A retrospective study in JAMA attempts to answer this question. The study explores the association between long-term mortality and various levels of cardiorespiratory fitness (CRF). CRF is a measure of how well your heart and lungs pump blood and oxygen throughout the body during prolonged bouts of exercise. The more fit you are, the higher your level of CRF. Regular exercise, and vigorous exercise, can both boost CRF.

The researchers looked at over 122,000 patients at a large academic medical center who underwent exercise testing on a treadmill, an objective measure of CRF. While the average age was 53, participants ranged in age from 18 to over 80. Similar to findings of previous studies, being fit was associated with living longer. This held true at any age. The researchers also saw a relationship between CRF and survival rates: the higher the level of fitness, the higher the survival rate. This was especially notable in older people and people with high blood pressure. And the survival benefit continued to climb with no upper limit.

What does this mean for all of us?

Unless there is a clear medical contraindication, we should all strive to achieve and maintain high levels of fitness. Current guidelines recommend 150 to 300 minutes per week of moderate aerobic activity (walking, running, swimming, biking), or 75 minutes of vigorous activity, or a mix of both. Twice-weekly resistance training to strengthen muscles is also recommended. Unfortunately, only about one in five adults and teens gets enough exercise to maintain good health.

Wondering where to start?

There's a place to start for everyone regardless of age or current fitness level.

• First, think safety. Walking and other low levels of exercise are generally safe for most people. But check with your doctor before starting or making changes to an exercise routine if you have a history of heart disease, or any other medical condition that might impact your exercise tolerance.
• Start small. You'll be more successful if you set the bar low. For example, start with a simple routine of walking 10 to 20 minutes three times per week. Every week or two, add five minutes per walk until you reach a goal of 30 minutes. Then, every week or two, add a day until you reach at least 150 minutes per week. Over time you can try to increase intensity. Remember, small goals are more achievable, and these little victories will continue to fuel your motivation.
• Don't be afraid of exercise or the gym. Any movement is good and is a step in the right direction. The gym intimidates many folks — perhaps you're overweight or inexperienced, and worry that others might stare or judge you. Everyone was new to exercise at one point in time. Focus on your purpose and avoid wasting energy on things that do not matter.
• Plan ahead. To maximize your success in adopting a long-term lifestyle change, plan ahead. Every week, look at your calendar ahead of time and commit to when you will exercise that week. Think of your opportunity to exercise as an appointment, rather than "I'll get to it if I have time."
• Expect to lose some battles. Keep in mind that realistically, most people will get derailed at some point as they work on a behavioral change. Do not let this crush your motivation. Instead, identify obstacles that may have interfered, strategize a solution moving forward, and try again.

Trying to get back into physical activity after a hiatus?

Take the first week to ease back into exercising. Avoid building up to your previous level of fitness too quickly to avoid injuring yourself.

Already active and wondering how to reap more benefits?

• Many people fall short on resistance training and are mostly focusing on cardio. Resistance training helps you build strength, thereby improving your overall cardiovascular fitness and performance.
• If you're short on time, consider a high-intensity interval workout. This will get you more bang for your buck.
• Vary your exercise routine to keep yourself challenged physically.

Too often, our health takes a back seat in the midst of busy careers and the multitude of responsibilities we take on in our lives. Optimizing your health through highly nutritious food choices and by getting enough sleep and exercise takes time and dedicated effort. But it is certainly worth it, and only gets easier over time as these new habits become ingrained.

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