Aerobic exercise — such as running, fast walking, cycling, and swimming — has long been seen as key to heart and lung health.
While aerobic exercise is a proven heart-protector, a growing body of evidence sees strength training as equally important.
And recent findings suggest that strength training yields unique benefits, such as possibly slashing your risk of suffering a stroke.
We reported on some of that preliminary research in Strength Training Tied to Unique Cardio Benefits.
New research reports from Latin America and Iowa State University add more evidence that strength training boosts cardiovascular health as much or more than aerobic exercise — and brings its own unique benefits.
Latin American study sees cardio benefits from strength workouts
Maia P. Smith, Ph.D., of St. George’s University presented this report — one of the first to differentiate the effects of strength versus aerobic workouts on heart risks — at the November, 2018 American College of Cardiology (ACC) Latin America Conference.
And their analysis supports growing evidence that "static" strength exercises such as weight lifting and pushups may reduce heart risks more than dynamic aerobic activities such as walking and cycling.
Professor Smith's team analyzed health and activity data from 4,086 American adults who’d participated in the 2005-2006 National Health and Nutrition Examination Survey (NHANES).
The 2005-2006 NHANES survey recorded the participants’ cardiovascular risks, including high blood pressure, obesity, diabetes and high cholesterol, as well as the volunteers’ self-reported activity levels, including static strength (resistance) exercise and dynamic aerobic activities.
And they look for any differences related to the age of the 4,086 participating adults by dividing them into two groups: 21 to 44 years old (younger group) and over 45 years old (older group).
Dr. Smith’s team found that 36% of younger and 25% of older adults engaged in static strength exercise, respectively, while 28% of younger and 21% of older adults engaged in dynamic aerobic exercise.
While both types of activity were associated with a 30 to 70% lower rate of cardiovascular disease risk factors, the link between exercise and better cardiovascular health was strongest for static strength exercise — and (perhaps unsurprisingly) the biggest resulting cardio benefits were seen in the younger adult group.
Importantly, Smith’s team adjusted the results to account for the known cardiovascular-health effects of age, ethnicity, gender and smoking.
Dr. Smith summarized their findings: “Both strength training and aerobic activity appeared to be heart healthy, even in small amounts, at the population level. However, static [strength] activity appeared more beneficial than dynamic [aerobic activity], and patients who did both types fared better than patients who simply increased the level of one type.”
Three Iowa State studies confirm heart benefit from modest strength training
Strength training gained more heart-health shine from a three-part study led by scientists from Iowa State University, which involved four other U.S. universities and one in China.
For the first part of the study, the international team analyzed data from 12,591 adults who’d participated in the Aerobics Center Longitudinal Study, to compare the participants’ exercise habits to three health outcomes:
And the results of the comparisons suggested that just one hour of strength per week training reduced the risks for all three outcomes.
In fact, lifting weights for less than an hour a week was linked to a 40 to 70% reduction in the risk for a heart attack or stroke.
And these benefits were seen even among people who didn’t engage in aerobic activities such as running or fast-walking. In other words — although it's better to also do aerobic exercise — strength training alone does a great deal for cardiovascular health.
Surprisingly, more wasn't better: people who did more than one hour of strength training per week didn’t gain significantly more risk reductions.
Two related studies from the same team involved analyses of exercise and health data from more than 7,000 men aged 18 to 83 years (average age 46) with normal cholesterol levels, who underwent extensive medical examinations at the famed Cooper Clinic in Dallas, Texas, between 1987 and 2006.
(We should note that the results were not adjusted to account for the effects of diet or medications, because data on those factors were not available.)
The results linked one hour of weekly strength exercise (compared with none) to a 29% reduction in the risk of developing metabolic syndrome — which promotes diabetes and heart disease — and a 32% reduction in the risk of developing high cholesterol (Bakker EA et al. 2017; Bakker EA et al. 2018).
While neither of those benefits depended on doing regular aerobic exercise, men who also engaged in aerobic exercise enjoyed a somewhat lower risk of developing high cholesterol.
This is how kinesiology professor DC (Duck-chul) Lee, characterized their findings: “People may think they need to spend a lot of time lifting weights, but just two sets of bench presses that take less than 5 minutes could be effective.”
Does this mean you need to rush out and join the gym? Lee says no: “Lifting any weight that increases resistance on your muscles is the key. My muscle doesn’t know the difference if I’m digging in the yard, carrying heavy shopping bags or lifting a dumbbell.”
Strength training options
So, what is strength training, and can you easily get an hour of it every week?
Strength training — also called resistance training — is any exercise or daily activity that causes your muscles to work against some type of external resistance (including your own body weight) to boost muscle mass and tone.
Strength training comes in two broad categories:
It’s wise to gain expert guidance, especially when starting out or when using weights and other resistance-training tools.
The world's many quick, body-based workouts for home or office typically (and should) combine the cardio benefits of resistance/strength training with the complementary cardio and pulmonary benefits of aerobic exercise.
Last year, we reported on one of the most efficient, well-studied routines in 7-Minute Fitness HIIT, under the heading “Johnson & Johnson’s 7-Minute Workout”.
That article also provided a link to a New York Times article with HIIT exercise illustrations and links to a free downloadable NYT mobile HIIT app.
Strength-training myths busted
There are a few myths about strength training that need to be busted as well.
First, one hour of strength training per week or so probably won’t change your shape dramatically. Instead, modest amounts of strength training simply enlarge and visibly define the exercised muscles.
Secondly, weight training may not cause significant weight gain or loss.
While muscle weighs more than fat, any added muscle tissue will also boost your metabolism, causing you to burn more calories while you’re at rest.
Thirdly, there’s no reason you can’t do a little strength training every day, provided you focus on a different muscle group daily, to give exercised muscles a chance to recover.
Finally, you don’t need to join a gym, since you can leverage your own body weight to create resistance.
Examples of body-weight exercises include pushups, lunges, crunches, pull-ups, and squats.
And you can get ample strength/resistance training at home with free weights, rubber bands, and tubes — just get some expert guidance, and never exercise through pain.