Frequency or Volume: Which One is More Important for Building Strong Muscles?
As a health and exercise professional, you know that some exercise is always better than none, which is why you collaborate with your clients to find ways to squeeze in movement and activity when they can—a walk after dinner, taking the stairs instead of the elevator, stretching during work breaks, or even doing some push-ups and sit-ups while watching television. But when time is really tight, is it more effective to exercise a little bit every day, or exercise for longer once a week?
The answer, based on new research from Edith Cowan University (ECU) in Perth, Australia, is good news for those who find it challenging to block off time for hour-long muscular-training workouts. The researchers concluded that a little bit of daily activity could well be the most beneficial approach, at least when it comes to building muscular strength.
In collaboration with Niigata University and Nishi Kyushu University in Japan, the four-week training study had three groups of participants perform an arm-resistance exercise. The exercise consisted of maximal voluntary eccentric biceps contractions performed on a machine that measures muscle strength in each muscle contraction. An eccentric contraction is when the muscle is lengthening, such as lowering a heavy dumbbell when performing a biceps curl.
Two groups performed 30 contractions per week, with one group doing six contractions a day for five days a week (6x5 group), while the other crammed all 30 contractions into a single day, once a week (30x1 group). The third group only performed six contractions one day a week. Over the course of the study, researchers measured participants’ changes in muscle strength and muscle thickness.
After four weeks, the group doing 30 contractions in a single day did not show any increase in muscle strength, although muscle thickness (an indicator of increase in muscle size) increased 5.8%.
The group doing six contractions once a week did not show any changes in muscle strength and muscle thickness.
However, the group performing six contractions per day, five days per week, experienced significant increases in muscle strength—more than 10%—with an increase in muscle thickness similar to the 30x1 group.
What the Research Means to Health and Exercise Professionals
Importantly, the increase in muscle strength of the 6x5 group was similar to the group in a previous study that performed only one 3-second maximal eccentric contraction per day for five days a week for four weeks.
Dr. Ken Nosaka, the director of exercise and sports science in the school of medical and health sciences at ECU and one of the study’s authors, explains that these studies continue to suggest very manageable amounts of exercise done regularly can have a real effect on people’s strength.
“People think they have to do a lengthy session of resistance training in the gym, but that’s not the case,” he says. “Just lowering a heavy dumbbell slowly six times a day is enough.”
According to Professor Nosaka, while the study required participants to exert maximum effort, early findings from current, ongoing research indicate similar results may be achieved without needing to push as hard as possible. “We only used the biceps curl exercise in this study, but we believe this would be the case for other muscles also, at least to some extent.”
Muscle strength is, of course, vital to good health and well-being, particularly as people grow older. “A decrease in muscle mass is a cause of many chronic diseases,” reminds Professor Nosaka. This includes cardiovascular disease, type 2 diabetes, some cancers, dementia, plus musculoskeletal problems such as osteoporosis.
While it is not yet known precisely why the body responds better to resistance exercises with eccentric contractions in smaller doses rather than bigger loads less frequently, researchers believe it may relate to how often the brain is asked to make a muscle perform in a particular manner. That said, you can’t ignore the importance of including adequate rest and recovery strategies when creating exercise programming for your clients.
“Muscle adaptions occur when we are resting; if someone was able to somehow train 24 hours a day, there would actually be no improvement at all,” says Professor Nosaka. “Muscles need rest to improve their strength and their muscle mass, but muscles appear to like to be stimulated more frequently.” He also explains that if a client is unable to exercise for a period, there is no value in trying to “make up” for it with a longer session later. “If someone’s sick and can’t exercise for a week, that’s fine, but it is better to just return to a regular exercise routine when [they’re] feeling better” he says.
Current physical activity guidelines urge adults to accumulate 150 minutes of moderate-intensity physical activity and perform muscular training twice per week. Professor Nosaka believes there should be greater emphasis on the importance of making exercise a daily activity, rather than hitting a weekly minute goal.
“If you’re just going to the gym once a week, it’s not as effective as doing a bit of exercise every day at home,” he says. “This research, together with our previous study, suggests the importance of accumulating a small amount of exercise each week, rather than just spending hours exercising once a week.”
Chris Gagliardi, ACE’s Scientific Education Content Manager, concurs. “When thinking in terms of “activity snacks,” we often focus on walking, stretching and other forms of movement, but we rarely talk about performing resistance training during activity breaks,” he says. “People know that resistance training is important, the Physical Activity Guidelines for Americans urge us to do it at least twice per week, but many people simply don’t do any resistance training at all.
Gagliardi thinks many clients may be more open to the idea of doing a little bit of muscular training each day, especially if they find it difficult to block out a larger chunk of time on their calendar. “Depending on a client’s goals, this method of sprinkling in resistance training for all major muscle groups could be a great option,” he says. At the top of this page, ACE Certified Professionals can exclusively access a total-body muscular-training program created by Gagliardi that is based on the research presented in this article.