Short-burst workouts good in well-rounded workout plan
Q: Our dad retired last spring, and since he's been home, he hasn't been getting much exercise. Our mom is getting worried about his health. I just read that working out for just 11 minutes a day makes a difference. Is that really true?
A: We think you're referring to the findings from a new study that, with an alluring "it takes only 11 minutes a day" promise, has been making a splash. It's part of a growing body of research that looks not only at what kind of physical activity makes us healthier, but also at how we perform those activities.
Over the last decade, and particularly in the last few years, we've seen a growing understanding that intensity and duration play sometimes surprising roles in exercise. In fact, we recently wrote about a different study, which looked at how much exercise helps lower mortality rates. That study also found 11 minutes to be a sweet spot when it comes to exercise beginning to make a difference.
With the proliferation of fitness trackers, loaded with precision tech to gauge the length and physical effects of each workout and measure progress over time, researchers now have access to new and expansive data pools. The value of brief bursts of activity has emerged, and the result is a new appreciation of the benefits of short and focused workouts.
In the study you're asking about, researchers from the Mayo Clinic in Minnesota and McMaster University in Canada created their own version of a well-regarded body weight workout. These are exercises such as jumping jacks, stair climbing, planks and squats that use one's own body weight for resistance. The exercise sequence was made up of one minute each of a specific body weight exercise, interspersed with a minute of walking or running in place. The 11 minutes also included a minute to warm up and cool down. The 20 study participants were asked to work as hard as was comfortable during each one-minute increment of exercise. Six weeks later, the 11-minute exercisers were in measurably better shape - a 7% increase in endurance - than a control group who did not add exercise to their daily routines.
While short-burst workouts are getting a lot of attention these days, it's important to stress they're just one part of a well-rounded exercise plan. The recommendation remains to get at least 150 minutes of moderate-intensity aerobic activity, or 75 minutes of vigorous aerobic activity, spread throughout the week. And don't forget about stretching and weight-bearing exercises. We humans are built for movement. Unless we remain active, we run the risk of sacrificing not only optimal physical and mental health, but all-important strength, balance and stability.
The top reason we hear from our patients about not getting enough exercise is that they don't have the time. But recent research shows that any amount of exercise at all can make a difference. Perhaps if you let your dad know he doesn't have to commit to a daily hour at the gym, he'll be willing to invest 10, or perhaps even 20, minutes each day on his health and well-being.
Q: I heard on the news that if your gut isn't in good shape, you'll probably get a worse case of COVID-19. Is that really true?
A: A study published earlier this year put forth an intriguing theory about a link between the state of someone's gut microbiome and the severity of their case of COVID-19.
Research has taught us that the vast colonies of microscopic creatures living in our guts are in constant communication with the brain and have an effect on everything from mood, emotions, sleep and weight to metabolism, blood-sugar control and a range of diseases. Considering this inextricable connection between the human gut microbiome and our health, looking into a potential relationship between the trillions of microbes in our intestinal tracts and COVID-19 seems like a logical step.
The study, published earlier this year in the journal Gut, builds upon previous inquiries into what role the gut may play in patients with COVID-19. Earlier studies have identified a measurable difference between the microbial composition of the guts of those patients and of people who were sick with a cold or the flu.
In this new study, researchers delved into the question in greater detail. They analyzed samples of blood and stool taken from 100 patients with COVID-19 whose disease was severe enough that they were admitted to the hospital and compared the results to samples drawn from 78 healthy control subjects. They discovered that species of certain bacteria that are known to play a role in the immune system were present in much lower numbers in the guts of the patients hospitalized with COVID-19. They also found larger populations of certain bacteria in the patients with COVID-19, including several that are associated with inflammation. The researchers saw this as evidence that an imbalance in certain bacterial colonies within someone's gut might influence how severe their illness could or would become.
They also found evidence of a potential link between these gut imbalances and the lingering symptoms known as long-haul COVID. For fellow science nerds, the bacterial overgrowth included a species known as Ruminococcus gnavus, which previous studies have shown to produce a simple sugar that causes inflammation. This bacterium has been linked to Crohn's disease and diverticulitis.
It is important to note that, although results of this study suggest a connection between certain gut microbiome imbalances and a more severe case of COVID-19, they do not offer conclusive proof. There's no way to know whether the specific array of microbes in these patients' guts existed before they became infected with the novel coronavirus, or if they arose as a result of the infection and subsequent illness. Still, with the novel coronavirus and COVID-19 so new to the world, every additional bit of data is, at the very least, interesting. With any luck, it may prove important enough to help develop a cure. In that vein, some are holding out hope that this line of research into the gut microbiome of COVID-19 patients may someday lead to microbe-based therapies, each one tailored to a person's specific gut microbiome.
• Dr. Eve Glazier is an internist and associate professor of medicine at UCLA Health. Dr. Elizabeth Ko is an internist and assistant professor of medicine at UCLA Health. Send your questions to askthedoctors@mednet.ucla.edu.