Here's Why Trainers Say HIIT Workouts Are the Most Effective

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Diet might ultimately be more impactful for weight loss, but don't take that as a cue to cut out your fitness routine altogether. To the contrary, more and more research to support the benefits of working out seems to emerge on a near-daily basis: From sleeping more soundly and boosting your mood to ensuring your metabolism is humming along at the highest speed possible, the reasons for logging regular sweat sessions abound.

And now, we can effectively add time travel to this ever-growing list. While scientists and fitness pros alike have told us for years that exercising regularly can keep us young, new research zeroes in on the exact workout that delivers on this promise most effectively—in fact, research says that this particular fitness regimen can "reverse the aging process" altogether. 

High Intensity Interval Training (HIIT) is officially the Mediterranean diet of working out—it can seriously do no wrong. These bursts of aerobic exercises are quick, convenient, and keep your metabolism churning long after you completed your workout, which effectively means you're burning fat with minimal effort. And now, research can confirm that this workout strategy can also reverse the clock. According to scientists at the Mayo Clinic, new research demonstrates that HIIT can reverse some aspects of aging on a cellular level.

HIIT workouts are so effective because you are working a large number of muscle groups at the same time at a high intensity,” says Grayson Wickham, doctor of physical therapy and certified strength and conditioning specialist (CSCS). “HIIT workouts essentially combine strength training and cardio.”

Meet the Expert

Grayson Wickham has his Doctorate in Physical Therapy and is also a certified strength and conditioning specialist (CSCS). He is the founder of Movement Vault and Lux Physical Therapy and Performance in New York City. He teaches mobility and movement workshops all over the world. 

How It Works

HIIT workouts are so effective because they produce results at the cellular level. The aerobic activity essentially enhances the way our cells produce protein—and since diminished protein synthesis is one of the most adverse signs of aging, this is quite notable.

“We encourage everyone to exercise regularly, but the take-home message for aging adults that supervised high-intensity training is probably best, because, both metabolically and at the molecular level, it confers the most benefits," says K. Sreekumaran Nair, an endocrinologist who helped lead the study. 

Wickham says that HIIT workouts improve your aerobic capacity. "A key biomarker for health and longevity is your aerobic capacity also known as your VO2 Max," he says. "The higher your VO2 Max is, the less likelihood you are to experience a cardiovascular issue or condition. Essentially, the higher your VO to Max is, the better your fitness level is. HIIT workouts have been shown to increase your VO2 Max greater than moderate intensity continuous training."

How To Get the Most From Your Workout

The study found that the benefits of HIIT hardly stop at reversing aging: Participants also improved their cardiorespiratory health, muscle mass, and insulin sensitivity, as well as the gene expression of their muscles. Another key takeaway from the scientists is that in order to significantly improve muscle tone, it's a good idea to add resistance training into your routine as well.

“It is pretty clear in the scientific literature, that the better your aerobic capacity is, and the more lean muscle mass you have, the greater your overall health and longevity will most likely be,” says Wickham. “There are obviously other factors such as one’s diet, stress levels, sleep, that also play into your strategy to reverse the aging process.”

How much should you exercise to get the most benefits to turn back the hands of time? Believe it or not, you can exercise too little...and too much. “If you exercise in a way that introduces too much stress to your body, too often, this could have a negative overall impact on your health,” he says.

To get the most effective workout to get that youthful glow, Wickham says you need to include both strength training and HIIT into your workouts. 

“Generally you will want to have three to five workout days per week,” he says. “Try to incorporate two to three strength training days per week, and three high intensity interval training days per week.”

 Wickham says you can do both strength training and HIIT on the same day, or separate them and do them on different days. “Your strength training workouts can be anywhere from 20 minutes to an hour in length. Your HIIT workouts can be anywhere from five to 20 minutes in length.”

Other Anti-Aging Workouts

If you aren’t a huge fan of HIIT workouts, rest assured that any type of exercise you do will be beneficial to your health. “When we break it down, all forms of exercise when performed at an appropriate dose for an individual have anti-aging benefits,” says Wickham. “These include low intensity continuous exercises such as running, biking, or walking. This also includes strength training to focus on building lean muscle mass.”

In addition, there are some people that should opt for other forms of exercise than HIIT. "Anyone that has a moderate to severe cardiovascular or neurological condition should not perform regular or modified high intensity training," says Wickham, who recommends checking with your doctor first.

Aerobic Exercise for Reversing Heart Damage

Exercise does more than just reverse aging on the outside, it also helps on the inside. Research has shown that exercise can reverse damage done to the heart if you start prior to age 65 and you exercise four to five times per week. 

The American Heart Association recommends you get at least 150 minutes per week, or 30 minutes per day for five days, of moderate-intensity aerobic activity. For those that are doing the HIIT workouts, they say you could do just 75 minutes of vigorous aerobic activity per week to reap the heart benefits. 

“The best exercises for your heart include any type of exercise that increases your heart rate within a healthy heart rate zone for you given your current fitness level and state of health,” says Wickham. “Generally speaking, all forms of exercise in the appropriate doses will provide benefits to your heart and cardiovascular system. The key here is performing the exercise type in the appropriate dose.”

Before increasing the intensity of your workout, he says it is important that you have good form at a normal pace. "Performing exercises with bad form and technique in a high intensity interval training workout can and will most likely lead to pain and injury at some point."

Strength Training to Preserve Muscles

It’s a fact of life that as we age we naturally lose muscle mass. In fact, we lose three to five percent per decade. 

“This is due to numerous factors including hormone levels declining, and decreased amount of activity,” says Wickham. “Studies have shown that generally the more lean muscle mass you have, the greater your health longevity will be. Strength training preserves and enhances your muscle mass during the constant breakdown and repair cycle that your body goes through during and after your workouts. This is why it is very important to maintain some level of strength training throughout your life.”

The good news is that you can preserve your muscle mass and even build it up. Make a point to incorporate strength training two to three times per week, focusing on all the major muscle groups. It is important you continue to challenge yourself. Your strength training should include at least eight exercises. Aim to perform 12 to 15 reps of each exercise. When you can perform 12 reps easily, it is time to increase the weight. 

In addition to a healthy diet and the right skincare treatments, make sure to incorporate exercise into your routine to turn back the hands of time. The addition of a HIIT workout and strength training four to five times per week is the key to a healthy body and glowing skin.

Article Sources
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  1. Robinson MM, Dasari S, Konopka AR, et al. Enhanced protein translation underlies improved metabolic and physical adaptations to different exercise training modes in young and old humansCell Metab. 2017;25(3):581‐592. doi:10.1016/j.cmet.2017.02.009


  3. Nellis R. Mayo Clinic discovers high-intensity aerobic training can reverse aging processes in adults. Mayo Clinic. March 10, 2017.




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