If you want to make the most of a short span of time for working out, consider a high-intensity workout.
With brief bouts of high-intensity interval training, it’s possible to achieve or even exceed the physical benefits that people get from spending much longer periods of time working out.
“Time is everything for people,” Jason Barone, a clinical director at an organization called Professional Physical Therapy, previously told Business Insider. “High-intensity training is kind of perfect for the busy schedule — you don’t need a gym, you can do it at your home, you’re looking at about a 20- to 30-minute workout.”
When Barone and other trainers talk about high-intensity workouts, a number of activities qualify. The basic idea is that people work out at close to full-on intensity for short periods of time instead of doing longer workouts at more moderate, 50-70% exertion levels. Some of these workouts include short sprints, some involve circuits of body-weight exercises, and others use weights or kettlebells.
High-intensity training is not always better than a more traditional exercise routine. There are good reasons to do longer workouts — they can help your body adapt to achieve certain fitness goals, such as preparing your joints and muscles for the strain of a long race like a marathon. But intense workouts are often the best way for athletes to improve performance.
They can have powerful effects on health too, helping people rev up metabolism to burn fat, lower blood pressure, and more.
Here’s why you might want to give high-intensity training a try — and what you can do to get started.
In one small study published in 2016, researchers had a group of men do workouts consisting of three 20-second bursts of all-out exertion, with some warm-up, cool-down, and rest in between sets. The results suggested those participants’ fitness levels improved as much as those of men who worked out for 45 minutes at moderate intensity.
Both groups showed almost a 20% gain in one measurement of the body’s ability to use oxygen — called VO2 peak — which the authors use to represent cardiorespiratory fitness. There was also a dramatic improvement in how all participants’ bodies handled blood sugar. The men in both groups also had a dramatically increased mitochondrial count in their muscles, a sign of good cellular function.
The difference is that one group got their workouts done much more quickly.
One review of research found that people who start doing high-intensity workout programs can improve insulin sensitivity by 23-58%. The studies analyzed in that review ranged from two to 16 weeks long.
Insulin sensitivity helps people’s bodies regulate blood sugar levels. Researchers think high-intensity training plays a role because the regimen improves the ability of muscles to take up glucose from blood so those muscles can be ready to jump into action.
Several studies have found that after 12 to 16 weeks of high-intensity training programs, people at risk of hypertension showed significant improvements in arterial stiffness (which leads to high blood pressure).
These high-intensity programs were more effective for improving that stiffness than conventional exercise routines.
Whenever you look at a training program designed to help someone become faster, stronger, or a better performer in a certain sport, that program will almost certainly include sets of high-intensity intervals.
That’s because these sorts of programs push people’s limits, which is what you need to do to improve at a sport.
High-intensity interval workouts are much more effective than pure endurance training at improving VO2Max (that commonly used measure of how well muscles use oxygen). Even people who don’t improve much with traditional exercise programs often see significant improvements after doing interval training.
On a basic level, any high-intensity interval program involves a warm up, followed by a few cycles of intense activity with short rest breaks in between.
That activity could be sprinting, swimming, cycling, or do body-weight exercises.
Researchers have studied bursts of activity as short as 20 seconds at a time, but most studies have people go at full intensity for between one and four minutes before they take a short break. Then they repeat the cycle.
Barone recommends that if you’re doing a new type of activity, you start at a beginner level. This is especially true if you are trying to get back into shape but haven’t been working out regularly. Don’t pick something that’s too complicated for you to do with proper form or technique. Start simple and work your way up to harder programs to avoid injuring yourself.
When going all-out, there’s a chance you could injure yourself if you aren’t warmed up. And that doesn’t mean quickly stretching and touching your toes, either.
Barone suggests doing a five-minute dynamic warmup that will help get your muscles ready to go. When warming up and stretching, focus on the muscles you’re going to use — your shoulders don’t need much attention if you’re going to be sprinting, for example, and your back shouldn’t get neglected if you’ll be swimming.
While high-intensity training by definition means you have to push yourself, make sure you don’t put yourself out of commission and miss your next workout. Try to complete every exercise with the best form you can.
“It’s good to push the body, but you need to listen to it as well,” Barone said. “Be aware of warning signs … don’t push through pain, that might mean you need to take it easy.”
If you feel a sharp or sudden twinge, stop and assess the situation before you continue.
High-intensity workouts can yield great benefits if you do them several times a week, perhaps balanced in between other longer workouts.
But the best form of exercise is one you can do regularly. If you find a routine you like enough to do on a consistent basis, that’s the way to see the most improvement over time.
Originally published on www.businessinsider.com.
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