Dr. Oz is amazed at 99-year-old Jose's muscles.

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Dan and Dr. Oz's next stop is the home of 99-year-old Jose, who tells them about his typical day. Jose says after breakfast he tends his garden and clears underbrush around his corn crops.

When he sees Jose squatting down and using a machete to cut weeds around his corn plants, Dr. Oz is dumbstruck. "He's whacking through this stuff better than any lawn mower you can buy. It's remarkable," he says. "I'm looking at a 99-year-old man doing a better job than I could taking out the underbrush here."

Dr. Oz asks to examine Jose further and finds that his daily chores have built up strong chest, stomach and leg muscles, which are crucial for aging well. Dr. Oz explains that the quadriceps—the large group of muscles on the front of the thigh—allow you to bend your hips and extend your knee and are crucial for walking. "If you can't walk a quarter-mile in five minutes, the chance that you'll be dead in three years is three times higher than if you can," he says. "It's a big deal."

One exercise you can do to strengthen the quadriceps is a basic squat. Make the motion of sitting in a chair, but don't sit all the way down. "Just go down close to it and get back up," Dr. Oz says.

For those who are too weak for this exercise, Dr. Oz recommends repeatedly sitting and standing in a chair without using the armrests. "It's simple things like that," he says. "And [the Nicoyans] make it part of their life."
As a reminder, always consult your doctor for medical advice and treatment before starting any program.