Exercise is a key component of aging gracefully, and is linked with not only improved physical health but also better cognitive performance.

The maintenance of fully functioning joints is an important part of enabling ac-tive seniors to participate in health-promoting athletic activity, experts agree.

Seniors today are working longer, traveling more and anticipate remaining active longer into life than their predecessors did.

With more than 14 percent of the U.S. population at least 65 years old, it’s no surprise that a Google search on “healthy aging” yields more than 18 million results.

The National Institutes of Health, or NIH, a national body that funds research and sets policy, has this to say about exercise for older people: “Being physically active can also help you stay strong and fit enough to keep doing the things you like to do as you get older. Making exercise and physical activity a regular part of your life can improve your health and help you maintain your independence as you age.”

Losing the ability to exercise can have grave consequences, the NIH warns.

“Lack of physical activity also can lead to more visits to the doctor, more hospitalizations and more use of medicines for a variety of illnesses,” according to the NIH.

Exercise can prevent or delay disease, help to manage stress and improve mood, and can help support a healthy and intellectually vibrant old age. Recent research from Finland involving more than 5,000 subjects suggests that participating in leisure time physical activity earlier in life promotes mobility in old age.

Given that today’s senior citizens are staying active longer and understand very well that mobility is linked to retaining independence, it’s not a surprise that joint health is consistently one of the top-selling categories of dietary supplements, with glucosamine and chondroitin combinations leading the pack.

Glucosamine, an amino acid that the body produces naturally, is part of the process to form and repair cartilage. It is thought that consuming glucosamine, which is usually made from shrimp shells, may increase new cartilage formation by providing the necessary building blocks. The usual dose is 1,000 mg each day for one to two months.

Studies on the effectiveness of glucosamine are inconclusive at this point. The science on chondroitin is more encouraging, however, if it is taken in the right amounts.

Chondroitin, a nutrient extracted from cow, pork or bird cartilage, is one of the main substances responsible for cartilage resiliency, and also plays a major role in blocking the reactions that break down cartilage over time. Not all supplements are created equal, however.

The Food and Drug Administration, or FDA, regulates dietary supplements ac-cording to safety and removes potentially harmful products from the market.

But the FDA does not assess the health benefits of supplements as it does for drugs, making it incumbent on consumers to educate themselves on dosage levels and ingredient quality issues to find supplements that give the best results.

With chondroitin supplements, for example, the benefit appears to be linked to dose and ingredient quality. Most clinical studies that support chondroitin efficacy used daily serving sizes ranging from 800 mg to 1,200 mg.

Chondroitin is widely prescribed as a slow-acting drug to treat osteoarthritis in European Union countries.