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HIIT workouts improve cellular health

Any exercise is better than sitting on the couch, but recent research suggests some training programs are better than others for slowing the aging process. If you’re hoping to live a long and healthy life, it’s time to consider regularly engaging in high-intensity interval training, or HIIT.

"High-intensity interval training doesn’t just improve your cardiovascular system and your muscles," explained Dr. Jason Scotti, Geisinger sports medicine specialist. "It improves certain markers for health down to the cellular level better than any other exercise studied so far."

What is HIIT?

HIIT is a training technique that alternates intense effort for a short period of time with less intense recovery periods. If you’re wondering if you’re working hard enough during the intense intervals, a good rule of thumb is that you should not be able to say more than a word or two during that portion of the workout. In short, it should be a very difficult challenge.

A few sample HIIT workouts:

  •  One minute of all-out sprinting, followed by a minute of easy jogging or walking. Repeat these sets three to five times.
  •  One minute of fast jumping jacks, followed by a minute of easy jogging in place. Repeat these sets three to five times.
  •  One minute of sprinting on a bike or exercise cycle, followed by one minute of easy pedaling. Repeat these sets three to five times.

"Before you start any exercise program, you should talk to your doctor first to check for any underlying conditions that would create a risk for your health," added Kelly Clark, LAT, ACT, sports medicine program manager, Geisinger Northeast. "This is especially important with HIIT workouts, since you’ll be pushing your body to its limit."

The benefits of HIIT

HIIT is a hit with your mitochondria, which are responsible for producing energy for your cells. When you do HIIT workouts, your cells produce more of the proteins your mitochondria use as fuel to create energy for cells.

Mitochondria are closely tied to the aging process. When they are damaged or start to function less efficiently, the cell starts to age. By keeping your mitochondria in top-notch shape, HIIT workouts help to slow the aging process.

Researchers looked at two groups of people to see how different exercise programs benefited them. When participating in regular HIIT workouts, younger people in the study showed a 49 percent increase in mitochondrial capacity, and older people experienced a 69 percent increase.

When compared to groups that did strength training exercises or strength training and low-intensity cardio workouts, the HIIT group came out on top for aging-related benefits. The strength training groups saw improvements in lean muscle mass, but only the HIIT group had health improvements at the cellular level. The key was HIIT’s ability to improve mitochondrial capacity.

"High-intensity interval training gives you the biggest return on your exercise investment," said Clark. "If you’re debating which type of exercise works best with your busy schedule, HIIT is the way to go."

Dr. Jason Scotti, MD, is a Geisinger sports medicine specialist. He sees patients at Geisinger Sports Medicine and Orthopaedics in Wilkes-Barre, and Mountain Top. To schedule an appointment with Dr. Scotti or another sports medicine specialist, please call 800-275-6401 or visit

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